Journal articles: 'Migratory Control'

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Sudarsono, Hamim, Rosma Hasibuan, and Damayanti Buchori. "BIOLOGI DAN TRANSFORMASI BELALANG KEMBARA LOCUSTA MIGRATORIA MANILENSIS MEYEN (ORTHOPTERA: ACRIDIDAE) PADA BEBERAPA TINGKAT KEPADATAN POPULASI DI LABORATORIUM." Jurnal Hama dan Penyakit Tumbuhan Tropika 5, no. 1 (2005): 24–31. http://dx.doi.org/10.23960/j.hptt.1524-31.

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Biology and Transformation of the Migratory Locust Locusta migratoria manilensis Meyen (Orthoptera: Acrididae) at Several Laboratory Population Density Levels. The migratory locust, Locusta migratoria manilensis Meyen (Orthoptera: Acrididae) is one of insect pests in Indonesia that undergoes a unique polymorphic biology. The locust develops a transformation phase which is triggered mainly by high population density. Its recent outbreaks in several regions of Indonesia cause major concern and control strategies must be developed to strengthen control efforts in the future. Its unique polymorphic phenomenon, therefore, must be investigated thoroughly for the basis of management of the outbreak. Due to its agility and its long range flying ability, the most realistic technique to study behavioral and morphological change of the locust is in controlled condition at a laboratory or a green house facility. The experiment was aimed to study effects of colony densities on the biology and transformation process of the migratory locust. More specifically, the experiment was to study effects of population density on the feeding activity, mortality rate, and the ratio of F/C and E/F of the migratory locust L. migratoria manilensis. The population densities were simulated in colonies at 2, 5, 10, 20, dan 30 couples per cage (cage size: 45x45x90 cm) reared in a green house. Results of the experiment show that, in general, higher densities of the migratory locust colonies tended to feed more rigorously than those of the less dense colonies. The locust remained in solitary phase at the density of 2-5 couples per cage whereas the transient phase occured at the density of 10-20 couples per cage. The colonies transformed to gregarious stage when their densities were 30 couples per cage or higher. Mortality percentage tended to be higher at colonies with higher density, especially for the third instar of the migratory locust.

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Tanaka, Seiji, and Dao-Hong Zhu. "Outbreaks of the migratory locust Locusta migratoria (Orthoptera: Acrididae) and control in China." Applied Entomology and Zoology 40, no. 2 (2005): 257–63. http://dx.doi.org/10.1303/aez.2005.257.

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Berthold, Peter. "Genetic control of migratory behaviour in birds." Trends in Ecology & Evolution 6, no. 8 (1991): 254–57. http://dx.doi.org/10.1016/0169-5347(91)90072-6.

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Kelson, Suzanne J., Stephanie M. Carlson, and Michael R. Miller. "Indirect genetic control of migration in a salmonid fish." Biology Letters 16, no. 8 (2020): 20200299. http://dx.doi.org/10.1098/rsbl.2020.0299.

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Migration is a complex trait that often has genetic underpinnings. However, it is unclear if migratory behaviour itself is inherited (direct genetic control), or if the decision to migrate is instead the outcome of a set of physiological traits (indirect genetic control). For steelhead/rainbow trout ( Oncorhynchus mykiss ), migration is strongly linked to a large genomic region across their range. Here, we demonstrate a shared allelic basis between early life growth rate and migratory behaviour. Next, we demonstrate that early life growth differs among resident/migratory genotypes in wild juveniles several months prior to migration, with resident genotypes achieving a larger size in their first few months of life than migratory genotypes. We suggest that the genetic basis of migration is likely indirect and mediated by physiological traits such as growth rate. Evolutionary benefits of this indirect genetic mechanism likely include flexibility among individuals and persistence of life-history diversity within and among populations.

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Auerswald, Lutz, and Gerd Gäde. "Endocrine control of TAG lipase in the fat body of the migratory locust, Locusta migratoria." Insect Biochemistry and Molecular Biology 36, no. 10 (2006): 759–68. http://dx.doi.org/10.1016/j.ibmb.2006.07.004.

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Mueller, Jakob C., Francisco Pulido, and Bart Kempenaers. "Identification of a gene associated with avian migratory behaviour." Proceedings of the Royal Society B: Biological Sciences 278, no. 1719 (2011): 2848–56. http://dx.doi.org/10.1098/rspb.2010.2567.

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Bird migration is one of the most spectacular and best-studied phenomena in behavioural biology. Yet, while the patterns of variation in migratory behaviour and its ecological causes have been intensively studied, its genetic, physiological and neurological control remains poorly understood. The lack of knowledge of the molecular basis of migration is currently not only limiting our insight into the proximate control of migration, but also into its evolution. We investigated polymorphisms in the exons of six candidate genes for key behavioural traits potentially linked to migration, which had previously been identified in several bird species, and eight control loci in 14 populations of blackcaps ( Sylvia atricapilla ), representing the whole range of geographical variation in migration patterns found in this species, with the aim of identifying genes controlling variation in migration. We found a consistent association between a microsatellite polymorphism and migratory behaviour only at one candidate locus: the ADCYAP1 gene. This polymorphism explained about 2.6 per cent of the variation in migratory tendency among populations, and 2.7–3.5% of variation in migratory restlessness among individuals within two independent populations. In all tests, longer alleles were associated with higher migratory activity. The consistency of results among different populations and levels of analysis suggests that ADCYAP1 is one of the genes controlling the expression of migratory behaviour. Moreover, the multiple described functions of the gene product indicate that this gene might act at multiple levels modifying the shift between migratory and non-migratory states.

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Ishida, Tadashi, Takuya Shimamoto, Maho Kaminaga, Takahiro Kuchimaru, Shinae Kizaka-Kondoh, and Toru Omata. "Microfluidic High-Migratory Cell Collector Suppressing Artifacts Caused by Microstructures." Micromachines 10, no. 2 (2019): 116. http://dx.doi.org/10.3390/mi10020116.

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The small number of high-migratory cancer cells in a cell population make studies on high-migratory cancer cells difficult. For the development of migration assays for such cancer cells, several microfluidic devices have been developed. However, they measure migration that is influenced by microstructures and they collect not only high-migratory cells, but also surrounding cells. In order to find high-migratory cells in cell populations while suppressing artifacts and to collect these cells while minimizing damages, we developed a microfluidic high-migratory cell collector with the ability to sort cancer cells according to cellular migration and mechanical detachment. High-migratory cancer cells travel further from the starting line when all of the cells are seeded on the same starting line. The high-migratory cells are detached using a stretch of cell adhesive surface using a water-driven balloon actuator. Using this cell collector, we selected high-migratory HeLa cells that migrated about 100m in 12 h and collected the cells.

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Garel, S., M. Garcia-Dominguez, and P. Charnay. "Control of the migratory pathway of facial branchiomotor neurones." Development 127, no. 24 (2000): 5297–307. http://dx.doi.org/10.1242/dev.127.24.5297.

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Facial branchiomotor (fbm) neurones undergo a complex migration in the segmented mouse hindbrain. They are born in the basal plate of rhombomere (r) 4, migrate caudally through r5, and then dorsally and radially in r6. To study how migrating cells adapt to their changing environment and control their pathway, we have analysed this stereotyped migration in wild-type and mutant backgrounds. We show that during their migration, fbm neurones regulate the expression of genes encoding the cell membrane proteins TAG-1, Ret and cadherin 8. Specific combinations of these markers are associated with each migratory phase in r4, r5 and r6. In Krox20 and kreisler mutant mouse embryos, both of which lack r5, fbm neurones migrate dorsally into the anteriorly positioned r6 and adopt an r6-specific expression pattern. In embryos deficient for Ebf1, a gene normally expressed in fbm neurones, part of the fbm neurones migrate dorsally within r5. Accordingly, fbm neurones prematurely express a combination of markers characteristic of an r6 location. These data suggest that fbm neurones adapt to their changing environment by switching on and off specific genes, and that Ebf1 is involved in the control of these responses. In addition, they establish a close correlation between the expression pattern of fbm neurones and their migratory behaviour, suggesting that modifications in gene expression participate in the selection of the local migratory pathway.

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Sharma, Aakansha, Devraj Singh, Shalie Malik, Neelu Jain Gupta, Sangeeta Rani, and Vinod Kumar. "Difference in control between spring and autumn migration in birds: insight from seasonal changes in hypothalamic gene expression in captive buntings." Proceedings of the Royal Society B: Biological Sciences 285, no. 1885 (2018): 20181531. http://dx.doi.org/10.1098/rspb.2018.1531.

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We hypothesized differences in molecular strategies for similar journeys that migrants undertake to reproduce in spring and to overwinter in autumn. We tested this in redheaded buntings ( Emberiza bruniceps ) photoinduced into spring and autumn migratory states, with winter and summer non-migratory states as controls. Compared with controls, buntings fattened, gained weight and showed Zugunruhe (nocturnal migratory restlessness) in the migratory state. Spring migration was associated with greater fat and body mass, and higher intensity of Zugunruhe , compared with autumn migration. Circulating corticosterone levels were higher in spring, while T3 levels were higher in autumn. Hypothalamic expression of thyroid hormone-responsive ( dio2 , dio3 ), light-responsive ( per2 , cry1 , adcyap1 ) and th (tyrosine hydroxylase, involved in dopamine biosynthesis) genes showed significant changes with transition from non-migratory to the migratory state. There were significantly higher mRNA expressions in autumn, except for higher th levels in the spring. Furthermore, the expression patterns of dnmt3a (not dnmt3b ) and tet2 genes suggested an epigenetic difference between the non-migrant and migrant periods, and the spring and autumn migrant periods. These results demonstrate for the first time seasonal transition in hypothalamic gene expressions, and suggest differences in regulatory strategies at the transcriptional level for spring and autumn migrations in songbirds.

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Dietrich, S., F. Abou-Rebyeh, H. Brohmann, et al. "The role of SF/HGF and c-Met in the development of skeletal muscle." Development 126, no. 8 (1999): 1621–29. http://dx.doi.org/10.1242/dev.126.8.1621.

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Hypaxial skeletal muscles develop from migratory and non-migratory precursor cells that are generated by the lateral lip of the dermomyotome. Previous work shows that the formation of migratory precursors requires the c-Met and SF/HGF genes. We show here that in mice lacking c-Met or SF/HGF, the initial development of the dermomyotome proceeds appropriately and growth and survival of cells in the dermomyotome are not affected. Migratory precursors are also correctly specified, as monitored by the expression of Lbx1. However, these cells remain aggregated and fail to take up long range migration. We conclude that parallel but independent cues converge on the migratory hypaxial precursors in the dermomyotomal lip after they are laid down: a signal given by SF/HGF that controls the emigration of the precursors, and an as yet unidentified signal that controls Lbx1. SF/HGF and c-Met act in a paracrine manner to control emigration, and migratory cells only dissociate from somites located close to SF/HGF-expressing cells. During long range migration, prolonged receptor-ligand-interaction appears to be required, as SF/HGF is expressed both along the routes and at the target sites of migratory myogenic progenitors. Mice that lack c-Met die during the second part of gestation due to a placental defect. Rescue of the placental defect by aggregation of tetraploid (wild type) and diploid (c-Met−/−) morulae allows development of c-Met mutant animals to term. They lack muscle groups that derive from migratory precursor cells, but display otherwise normal skeletal musculature.

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Sudarsono, Hamim. "HAMA BELALANG KEMBARA (LOCUSTA MIGRATORIA MANILENSIS MEYEN): FAKTA DAN ANALISIS AWAL LEDAKAN POPULASI DI PROVINSI LAMPUNG." Jurnal Hama dan Penyakit Tumbuhan Tropika 3, no. 2 (2003): 51–56. http://dx.doi.org/10.23960/j.hptt.2351-56.

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Migratory locust (Locusta migratoria manilensis Meyen) : Preliminary facts and analyzes on the population outbreaks in Lampung Province. The migratory locust (locally known as belalang kembara), Locusta migratoria manilensis Meyen (Orthoptera: Acrididae), has become a major insect pest in Lampung in recent years since its outbreak in 1998. Thousand hectares of agricultural fields were severely destroyed by the locust populations during the course of the outbreak. Local as well as national government were caught in surprised by the population upsurge with little information and technology available for controlling the pest. First presence of locust population was recorded in Kecamatan Pakuan Ratu in 1990. Area damage in the first year was ca. 60 ha. The population grew steadily over the years and reached its peak in April-May of 1998 when thousands of corn and rice fields were severely damaged. Country roads and fields were filled with millions of locust nymphs. Records of locust attacks during preliminary outbreaks from 1990 to 1998 also indicated that the insect started its outbreak from the same areas during those years, i.e. North Lampung District and northern Tulang Bawang District (two of the outmost northern of Lampung Province). Insect pest control experts were very concerned that the locust has established its populations in the region and could cause significant loss in the upcoming years. Control strategy and techniques based on the insect biology and population dynamics, therefore, should be explored and developed to manage future outbreaks. This paper discusses and analyzes preliminary facts and information on the migratory locust and possible strategies that could be implemented for managing the locust.

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Ogonowski, Mark S., and Courtney J. Conway. "Migratory decisions in birds: extent of genetic versus environmental control." Oecologia 161, no. 1 (2009): 199–207. http://dx.doi.org/10.1007/s00442-009-1356-3.

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Scanlan, J. C., W. E. Grant, D. M. Hunter, and R. J. Milner. "Habitat and environmental factors influencing the control of migratory locusts (Locusta migratoria) with an entomopathogenic fungus (Metarhizium anisopliae)." Ecological Modelling 136, no. 2-3 (2001): 223–36. http://dx.doi.org/10.1016/s0304-3800(00)00424-5.

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Kidd, N. A. C., and A. M. Cleaver. "The control of migratory urge in aphis fabae scopoli (hemiptera: aphididae)." Bulletin of Entomological Research 76, no. 1 (1986): 77–87. http://dx.doi.org/10.1017/s0007485300015303.

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AbstractSome flightworthy alate exules of Aphis fabae Scopoli reproduce before taking off while others do not. This difference in behaviour is influenced by crowding and has previously been taken as an indication of the urge to migrate, although it has never been conclusively demonstrated. In this study, the flight performance of those aphids depositing some nymphs before take-off (‘flyers’) was compared with those which did not (‘migrants’). In fact, no significant difference was found between migrants and flyers in any of the aspects of post-take-off flight or settling behaviour tested. In tethered flight, large alatae flew for longer than small ones, irrespective of their pre-flight reproductive behaviour. In free flight, however, large alatae flew for a shorter period before actively landing on a plant. Large alatae were also subsequently more reluctant to leave the plant than small alatae, spending more time in sedentary activities such as probing and less time preparing to take off. It is concluded, therefore, that migratory urge is related more to aphid size, a product of plant nutritive quality, than to take-off urge, as measured by pre-flight reproductive behaviour. However, as high population densities tend to occur when the nutritional quality of the host is declining, take-off urge and migratory urge are likely to be synchronized in the field.

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Bairlein, F., and E. Gwinner. "Nutritional Mechanisms and Temporal Control of Migratory Energy Accumulation in Birds." Annual Review of Nutrition 14, no. 1 (1994): 187–215. http://dx.doi.org/10.1146/annurev.nu.14.070194.001155.

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Patel, Mitul K., and Benjamin G. Davis. "Control of Phosphoryl Migratory Transesterifications Allows Regioselecive Access to Sugar Phosphates." Organic Letters 15, no. 2 (2013): 346–49. http://dx.doi.org/10.1021/ol303271z.

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Bulte, Marc, and Franz Bairlein. "Endogenous control of migratory behavior in Alaskan Northern Wheatears Oenanthe oenanthe." Journal of Ornithology 154, no. 2 (2012): 567–70. http://dx.doi.org/10.1007/s10336-012-0920-5.

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Nelson, Michael E. "Development of migratory behavior in northern white- tailed deer." Canadian Journal of Zoology 76, no. 3 (1998): 426–32. http://dx.doi.org/10.1139/z97-207.

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I examined the development of migratory behavior in northern white-tailed deer (Odocoileus virginianus) from 1975 to 1996 by radio-tracking adult females and their fawns. Of 40 migratory fawns with radio-collared mothers, all returned from winter ranges to their mothers' summer ranges, as did 36 fawns with unknown mothers. Of 1.5- to 3.0-year-old daughters with radio-collared mothers, 67-80% continued migrating with mothers to their traditional summer ranges. Eighty-four percent (16/19) of yearling dispersers continued migratory behavior after replacing their natal summer ranges with their dispersal ranges, and 88% (14/16) of these continued migrating to their natal winter ranges, some through at least 6.5 years of age. Twenty percent (4/20) of nonmigratory fawns dispersed as yearlings, and two became migratory between their dispersal summer ranges and new winter ranges, one through 4.9 years of age and another through 6.5 years. Seven fawns changed their movement behavior from migratory to nonmigratory or vice versa as yearlings or when older, indicating that migratory behavior is not under rigid genetic control. Thus, the adaptiveness of migration must depend upon natural selection operating upon varying capacities and propensities to learn and mimic long-distance movements and not upon migratory behavior directly.

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Abdelatti, Zainab Ali Saad, and Manfred Hartbauer. "Plant oil mixtures as a novel botanical pesticide to control gregarious locusts." Journal of Pest Science 93, no. 1 (2019): 341–53. http://dx.doi.org/10.1007/s10340-019-01169-7.

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Abstract For thousands of years, large locust swarms have caused severe problems in agriculture. People fight against current outbreaks by using chemical pesticides or an insect fungus known as Green Muscle™. While chemical pesticides may be harmful for humans and non-target species, the sporulation of the fungus takes a long period of time and requires conditions of high humidity that are not always found in the field. In this study, we tested the toxicity of a linseed oil/bicarbonate emulsion against gregarious desert locusts and screened for plant essential oils that enhance its toxicity. Finally, we combined three essential oils to develop a novel formulation that is effective against the desert and migratory locust species after single spray treatment. Within 24 h, this formulation caused a mean mortality rate of 80% and 100% of desert and migratory locusts, respectively. Its toxicity is based on a synergistic effect resulting from the combination of caraway, orange peel and wintergreen oils. In addition, we tested this botanical pesticide on two beetle species regarded either as alternative or beneficial non-target species. The first species, mealworm beetles, did not suffer from the spray treatment and behaved normally after 8 days. In contrast, 67.7% of ladybird adults died in the same time span. Interestingly, the growth of wheat seedlings was almost unaffected by spraying this botanical pesticide. These results suggest this botanical pesticide can be used as a strong agent against desert and migratory locusts, but needs to be used with care to minimize unwanted side effects on the ecosystem.

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Yan, Long, Xixi Wang, Zhengce An, et al. "Enhancing upconversion of manganese through spatial control of energy migration for multi-level anti-counterfeiting." Nanoscale 13, no. 33 (2021): 13995–4000. http://dx.doi.org/10.1039/d1nr03836b.

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We report a mechanistic strategy to enhance the upconversion of Mn2+ by designing a migratory NaGdF4 interlayer in the core–shell nanostructure, showing great potential in multi-level anti-counterfeiting.

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Feichtinger, G., and A. Novak. "A note on the optimal exploitation of migratory fish stocks." Dynamics and Control 2, no. 3 (1992): 255–63. http://dx.doi.org/10.1007/bf02169516.

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Buckley, S., B. Driscoll, W. Shi, K. Anderson, and D. Warburton. "Migration and gelatinases in cultured fetal, adult, and hyperoxic alveolar epithelial cells." American Journal of Physiology-Lung Cellular and Molecular Physiology 281, no. 2 (2001): L427—L434. http://dx.doi.org/10.1152/ajplung.2001.281.2.l427.

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Alveolar epithelial cell (AEC) migration mediated by matrix metalloproteinases (MMPs) is required for lung development and repair after injury such as hyperoxia. Of specific interest in lung remodeling are the gelatinases, which are upregulated in AEC after hyperoxia. We correlated migration and gelatinase production in AEC cultured from fetal, adult, and hyperoxic rats. Fetal AEC (19–20 days) had higher MMP-2 and MMP-9 gelatinase expression than adult AEC, with fivefold higher MMP-9 activity, and were migratory through gelatin, responding to epidermal growth factor, keratinocyte growth factor, and fibroblast growth factor-10. MMP-2 and MMP-9 expression and migratory activity could be detected from the time of plating. In contrast, adult AEC migrated and expressed MMP-2 and MMP-9 proteins only after 48 h of culture. AEC from hyperoxic rats were significantly more migratory through gelatin than control adult AEC, with significantly higher MMP-9 activity. Inhibition of MMPs with doxycycline reduced the migration of AEC from hyperoxic rats to the level of control adult AEC. Fibronectin-cultured “hyperoxic” AEC acquired a temporary capacity for migration similar to the A549 lung cancer cell line, which is both highly migratory and invasive and is derived from the AEC type 2 lineage. These data suggest that MMP activity is associated with a migratory phenotype in fetal, hyperoxic, and transformed AEC in vitro, and we speculate that MMPs may play a key mechanistic role in AEC migration in vivo during lung development and repair.

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Shimizu, Yuko, Yudai Nishide, Seiji Tanaka, et al. "Gregarization of the migratory locust Locusta migratoria (Orthoptera: Acrididae) and prompt control on a subtropical island in Okinawa, Japan." International Journal of Tropical Insect Science 32, no. 03 (2012): 148–57. http://dx.doi.org/10.1017/s1742758412000239.

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Mentel, Tim, Carsten Duch, Heike Stypa, Gerhard Wegener, Uli Müller, and Hans-Joachim Pflüger. "Central Modulatory Neurons Control Fuel Selection in Flight Muscle of Migratory Locust." Journal of Neuroscience 23, no. 4 (2003): 1109–13. http://dx.doi.org/10.1523/jneurosci.23-04-01109.2003.

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Wilmers, Christopher C., and Taal Levi. "Do irrigation and predator control reduce the productivity of migratory ungulate herds?" Ecology 94, no. 6 (2013): 1264–70. http://dx.doi.org/10.1890/12-0499.1.

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Tripathi, B. K. "Circadian control of photoperiodic responses in a female migratory bunting (Emberiza bruniceps)." General and Comparative Endocrinology 66, no. 3 (1987): 301–5. http://dx.doi.org/10.1016/0016-6480(87)90238-3.

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Goto, Daisuke, Martin J. Hamel, Mark A. Pegg, Jeremy J. Hammen, Matthew L. Rugg, and Valery E. Forbes. "Divergent density feedback control of migratory predator recovery following sex‐biased perturbations." Ecology and Evolution 10, no. 9 (2020): 3954–67. http://dx.doi.org/10.1002/ece3.6153.

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Vrieze, Lance A., and Peter W. Sorensen. "Laboratory assessment of the role of a larval pheromone and natural stream odor in spawning stream localization by migratory sea lamprey (Petromyzon marinus)." Canadian Journal of Fisheries and Aquatic Sciences 58, no. 12 (2001): 2374–85. http://dx.doi.org/10.1139/f01-179.

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This study used large laboratory mazes and natural stream waters to test the role of olfactory cues, including a pheromone released by larvae, in spawning stream localization by migratory sea lamprey (Petromyzon marinus). We found that migratory lamprey strongly prefer stream water over lake water and that this response is dependent upon a functional olfactory system. Responses persisted among migratory lamprey even after stream water was diluted a thousand times but were not seen among non-migratory lamprey. Experiments using waters from five streams demonstrated that a larval pheromone is a key determinant of stream attractiveness: water from streams with larval populations were consistently more attractive than those without, and adding larval odor to the latter reversed this relationship. Larval odor was attractive at low, realistic concentrations, especially when presented together with natural stream water, suggesting that streams contain other odors that synergize the actions of the pheromone. Some, but not all, of the activity of the larval pheromone could be explained by two bile acids released by larvae (petromyzonol sulfate and allocholic acid). Together, these results strongly suggest that migratory lamprey locate streams using a larval pheromone. This cue could be useful in lamprey control.

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Bourouiba, L., Jianhong Wu, S. Newman, et al. "Spatial dynamics of bar-headed geese migration in the context of H5N1." Journal of The Royal Society Interface 7, no. 52 (2010): 1627–39. http://dx.doi.org/10.1098/rsif.2010.0126.

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Virulent outbreaks of highly pathogenic avian influenza (HPAI) since 2005 have raised the question about the roles of migratory and wild birds in the transmission of HPAI. Despite increased monitoring, the role of wild waterfowl as the primary source of the highly pathogenic H5N1 has not been clearly established. The impact of outbreaks of HPAI among species of wild birds which are already endangered can nevertheless have devastating consequences for the local and non-local ecology where migratory species are established. Understanding the entangled dynamics of migration and the disease dynamics will be key to prevention and control measures for humans, migratory birds and poultry. Here, we present a spatial dynamic model of seasonal migration derived from first principles and linking the local dynamics during migratory stopovers to the larger scale migratory routes. We discuss the effect of repeated epizootic at specific migratory stopovers for bar-headed geese ( Anser indicus ). We find that repeated deadly outbreaks of H5N1 on stopovers during the autumn migration of bar-headed geese could lead to a larger reduction in the size of the equilibrium bird population compared with that obtained after repeated outbreaks during the spring migration. However, the opposite is true during the first few years of transition to such an equilibrium. The age-maturation process of juvenile birds which are more susceptible to H5N1 reinforces this result.

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Zieske, J. D., G. Bukusoglu, and I. K. Gipson. "Enhancement of vinculin synthesis by migrating stratified squamous epithelium." Journal of Cell Biology 109, no. 2 (1989): 571–76. http://dx.doi.org/10.1083/jcb.109.2.571.

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A 110-115-kD protein is present at levels 27-fold higher in migratory epithelium in the rat cornea than in stationary epithelium. This protein represents 2.7% of the total protein in migratory epithelium 6-h postabrasion wound and 0.1% of the total protein in stationary epithelium. Our findings demonstrate that this 110-115-kD protein is vinculin. In Western blots comparing proteins from migratory and control epithelium, antibody against vinculin cross-reacted with the 110-115-kD protein. Using immunoslot blots, vinculin was determined to be present at maximal levels 6 h postabrasion wound, at levels 22- and 8-fold higher than control at 18 and 48 h, respectively, returning to control levels 72 h postwounding. Vinculin was also localized by indirect immunohistochemistry in migrating corneal epithelium. 3-mm scrape wounds were allowed to heal in vivo for 20 h. In flat mounts of these whole wounded corneas, vinculin was localized as punctate spots in the leading edge of migrating epithelium. In cryostat sections, vinculin was localized as punctate spots along the basal cell membranes of the migrating sheet adjacent to the basement membrane and in patches between cells as well as diffusely throughout the cell. Only very diffuse localization with occasional punctate spots between adjacent superficial cells was present in stationary epithelium. The increased synthesis of vinculin during migration and the localization of vinculin at the leading edge of migratory epithelium suggest that vinculin may be involved in cell-cell and cell-substrate adhesion as the sheet of epithelium migrates to cover a wound.

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BLACKMAN, EMILY B., CHRISTOPHER S. DEPERNO, CHRISTOPHER E. MOORMAN, and M. NILS PETERSON. "Avian Influenza Testing of American Woodcock in an Agricultural Landscape." Journal of North Carolina Academy of Science 127, no. 2 (2011): 189–91. http://dx.doi.org/10.7572/2167-5880-127.2.189.

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Abstract The potential for migratory bird species to transfer pathogenic Eurasian strains of avian influenza to the Americas has created international concern over monitoring efforts. Avian influenza has been isolated in multiple migratory shorebird species, and those that spend time in agricultural areas are more likely to share the virus with poultry. Scolopax minor (American Woodcock) are migratory and winter in agricultural landscapes throughout coastal North Carolina. Thirty nine woodcock were tested during February 2009 and December–March 2009–2010 for Type A avian influenza virus; all tests were negative. To our knowledge, this is the first study to evaluate woodcock for avian influenza. Wildlife disease surveillance, especially testing of novel species, is critical to monitor and control virus emergence and spread between wild and domestic populations.

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Alomenu, H. S. "Current trends in African Migratory Locust plague prevention." Outlook on Agriculture 14, no. 4 (1985): 165–73. http://dx.doi.org/10.1177/003072708501400402.

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From the dawn of civilisation, locusts have been one of the great agricultural plagues, stripping vast areas bare of vegetation as they relentlessly advance. Experience shows that the most effective control measure is to attack the pest at its breeding grounds in the Niger Delta area as soon as it shows signs of swarming. Unfortunately, the prolonged sahelian drought – which for some years has put a natural brake on breeding – has encouraged complacency about the risks of another resurgence when this comes to an end.

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Tanaka, Seiji. "The role of [His7]-corazonin in the control of body-color polymorphism in the migratory locust, Locusta migratoria (Orthoptera: Acrididae)." Journal of Insect Physiology 46, no. 8 (2000): 1169–76. http://dx.doi.org/10.1016/s0022-1910(99)00228-0.

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Santiago, Alicia, and Carol A. Erickson. "Ephrin-B ligands play a dual role in the control of neural crest cell migration." Development 129, no. 15 (2002): 3621–32. http://dx.doi.org/10.1242/dev.129.15.3621.

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Little is known about the mechanisms that direct neural crest cells to the appropriate migratory pathways. Our aim was to determine how neural crest cells that are specified as neurons and glial cells only migrate ventrally and are prevented from migrating dorsolaterally into the skin, whereas neural crest cells specified as melanoblasts are directed into the dorsolateral pathway. Eph receptors and their ephrin ligands have been shown to be essential for migration of many cell types during embryonic development. Consequently, we asked if ephrin-B proteins participate in the guidance of melanoblasts along the dorsolateral pathway, and prevent early migratory neural crest cells from invading the dorsolateral pathway. Using Fc fusion proteins, we detected the expression of ephrin-B ligands in the dorsolateral pathway at the stage when neural crest cells are migrating ventrally. Furthermore, we show that ephrins block dorsolateral migration of early-migrating neural crest cells because when we disrupt the Eph-ephrin interactions by addition of soluble ephrin-B ligand to trunk explants, early neural crest cells migrate inappropriately into the dorsolateral pathway. Surprisingly, we discovered the ephrin-B ligands continue to be expressed along the dorsolateral pathway during melanoblast migration. RT-PCR analysis, in situ hybridisation, and cell surface-labelling of neural crest cell cultures demonstrate that melanoblasts express several EphB receptors. In adhesion assays, engagement of ephrin-B ligands to EphB receptors increases melanoblast attachment to fibronectin. Cell migration assays demonstrate that ephrin-B ligands stimulate the migration of melanoblasts. Furthermore, when Eph signalling is disrupted in vivo, melanoblasts are prevented from migrating dorsolaterally, suggesting ephrin-B ligands promote the dorsolateral migration of melanoblasts. Thus, transmembrane ephrins act as bifunctional guidance cues: they first repel early migratory neural crest cells from the dorsolateral path, and then later stimulate the migration of melanoblasts into this pathway. The mechanisms by which ephrins regulate repulsion or attraction in neural crest cells are unknown. One possibility is that the cellular response involves signalling to the actin cytoskeleton, potentially involving the activation of Cdc42/Rac family of GTPases. In support of this hypothesis, we show that adhesion of early migratory cells to an ephrin-B-derivatized substratum results in cell rounding and disruption of the actin cytoskeleton, whereas plating of melanoblasts on an ephrin-B substratum induces the formation of microspikes filled with F-actin.

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de Blaquière, Gail E., Felicity E. B. May, and Bruce R. Westley. "Increased expression of both insulin receptor substrates 1 and 2 confers increased sensitivity to IGF-1 stimulated cell migration." Endocrine-Related Cancer 16, no. 2 (2009): 635–47. http://dx.doi.org/10.1677/erc-08-0216.

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Insulin-like growth factors (IGFs) are thought to promote tumour progression and metastasis in part by stimulating cell migration. Insulin receptor substrate-1 (IRS-1) and IRS-2 are multisite docking proteins positioned immediately downstream from the type I IGF and insulin receptors. IRS-2 but not IRS-1 has been reported to be involved in the migratory response of breast cancer cells to IGFs. The purpose of this investigation was to determine if IRS-1 is involved in, and to assess the contributions of IRS-1 and IRS-2 to, the migratory response of breast cancer cells to IGFs. The expression of IRS-1 and IRS-2 varied considerably between ten breast cancer cell lines. Oestrogen increases expression of the type I IGF receptor, IRS-1 and IRS-2 in MCF-7 and ZR-75 cells. Oestrogens may control the sensitivity of breast cancer cells to IGFs by regulating the expression of components of the IGF signal transduction pathway. The migratory response to a range of IGF-1 concentrations was measured in MCF-7 and MDA-MB-231 breast cancer cells in which IRS-1 and IRS-2 levels were modulated using a doxycycline-inducible expression system. Induction of both IRS-1 and IRS-2 expression increased the sensitivity of the migratory response to IGF-1 but did not increase the magnitude of the response stimulated at higher concentrations of IGF-1. Knockdown of IRS-1, IRS-2 and the type I IGF receptor in MCF-7 and MDA-MB-2231 cells decreased sensitivity to IGF-1. We conclude that both IRS-1 and IRS-2 control the migratory response of breast cancer cells to IGF-1 and may, therefore, be key molecules in determining breast cancer spread.

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Trueman, E. R. "The control of burrowing and the migratory behaviour of Donax denticulatus (Bivalvia: Tellinacea)." Journal of Zoology 165, no. 4 (2009): 453–69. http://dx.doi.org/10.1111/j.1469-7998.1971.tb02199.x.

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Shin, Jung-Youn, Hong Nam Kim, Suk Ho Bhang, et al. "Topography-Guided Control of Local Migratory Behaviors and Protein Expression of Cancer Cells." Advanced Healthcare Materials 6, no. 16 (2017): 1700155. http://dx.doi.org/10.1002/adhm.201700155.

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Massa, Renato, and Peter J. Sharp. "The photoperiodic control of concentrations of luteinizing hormone in male migratory chaffinchesFringilla coelebsL." Bolletino di zoologia 54, no. 3 (1987): 251–53. http://dx.doi.org/10.1080/11250008709355591.

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Huang, Jinshu, Long Yan, Songbin Liu, Nan Song, Qinyuan Zhang, and Bo Zhou. "Dynamic Control of Orthogonal Upconversion in Migratory Core–Shell Nanostructure toward Information Security." Advanced Functional Materials 31, no. 14 (2021): 2009796. http://dx.doi.org/10.1002/adfm.202009796.

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Chander, Mahesh, MS Kannadhasan, and D. Bardhan. "Migratory Sheep Farming Practices in Cauvery Delta Zone in Tamil Nadu." INDIAN JOURNAL OF VETERINARY SCIENCES AND BIOTECHNOLOGY 16, no. 01 (2020): 62–65. http://dx.doi.org/10.21887/ijvsbt.16.1.14.

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Migratory sheep, due to its movement, poses threat of spreading diseases among small ruminants. Considering this, the study was carried out to identify the focus area of extension intervention among the migratory sheep farmers to disseminate scientifically recommended practices which minimize disease risk and enhance flock health. The study was conducted following ex post fact research design at Venganur village, Cuddalore district, Tamil Nadu. Using a semi-structured interview schedule, data were personally collected from 30 migratory sheep farmers who were selected purposively. The findings were subjected to focussed group interview involving seven farmers. The results envisaged a wider difference among the farmers from 100 per cent non-adoption of balanced ration to 100.00 per cent adoption of deworming. Therefore, extension interventions need to be intensified to educate the farmers on technologies which help in disease prevention and control.

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De Luca, Giancarlo, Patrizio Mariani, Brian R. MacKenzie, and Matteo Marsili. "Fishing out collective memory of migratory schools." Journal of The Royal Society Interface 11, no. 95 (2014): 20140043. http://dx.doi.org/10.1098/rsif.2014.0043.

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Animals form groups for many reasons, but there are costs and benefits associated with group formation. One of the benefits is collective memory. In groups on the move, social interactions play a crucial role in the cohesion and the ability to make consensus decisions. When migrating from spawning to feeding areas, fish schools need to retain a collective memory of the destination site over thousands of kilometres, and changes in group formation or individual preference can produce sudden changes in migration pathways. We propose a modelling framework, based on stochastic adaptive networks, that can reproduce this collective behaviour. We assume that three factors control group formation and school migration behaviour: the intensity of social interaction, the relative number of informed individuals and the strength of preference that informed individuals have for a particular migration area. We treat these factors independently and relate the individuals’ preferences to the experience and memory for certain migration sites. We demonstrate that removal of knowledgeable individuals or alteration of individual preference can produce rapid changes in group formation and collective behaviour. For example, intensive fishing targeting the migratory species and also their preferred prey can reduce both terms to a point at which migration to the destination sites is suddenly stopped. The conceptual approaches represented by our modelling framework may therefore be able to explain large-scale changes in fish migration and spatial distribution.

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Eikenaar, Cas, Florian Müller, Clara Leutgeb, et al. "Corticosterone and timing of migratory departure in a songbird." Proceedings of the Royal Society B: Biological Sciences 284, no. 1846 (2017): 20162300. http://dx.doi.org/10.1098/rspb.2016.2300.

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Bird migration entails replenishing fuel stores at stopover sites. There, individuals make daily decisions whether to resume migration, and must also decide their time of departure. Variation in departure timing affects the total time required to complete a migratory journey, which in turn affects fitness through arrival time at the breeding and wintering grounds. It is well established that stopover departure decisions are based on cues from innate rhythms, intrinsic factors and extrinsic factors. Yet, virtually nothing is known about the physiological mechanism(s) linking these cues to departure decisions. Here, we show for a nocturnal migratory songbird, the northern wheatear ( Oenanthe oenanthe ), that baseline corticosterone levels of birds at stopover increased both over the migratory season and with wind assistance towards the migratory destination. Corticosterone in turn predicted departure probability; individuals with high baseline corticosterone levels were more likely to resume migration on a given night. Corticosterone further predicted the departure time within the night, with high baseline levels being associated with early departures. These novel findings indicate that corticosterone may be mediating between departure cues and the timing of departure from a stopover site, which is a major step towards understanding the hormonal control of animal migration.

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López Riopedre, José. "Migraciones “Al Margen”: grupos rumanos, diversidad y control social." RIEM. Revista internacional de estudios migratorios 7, no. 4 (2018): 229. http://dx.doi.org/10.25115/riem.v7i4.1966.

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Introducción: Este artículo propone una aproximación socio-etnográfica a aquellos grupos de la circulación migratoria rumana que quedan relegados “al margen” y ubicados estratégica y simbólicamente “al otro lado”, esto es, al margen de la ley, la sociedad y fuera del foco de atención de las ciencias sociales. Así, nos detendremos en las brigadas, formaciones de jóvenes que organizan sus actividades en torno a los delitos contra la propiedad y la práctica de la prostitución trasnacionales; y los clanes romaníes, grupos con vínculo familiar que desempeñan actividades como la recogida y venta de chatarra, las tareas agrícolas de temporada o la mendicidad.Método: El enfoque biográfico se sustenta en la etnografía “multi-situada” (España/Rumanía), dando especial relieve a la construcción de contextos de convivencia e intimidad con los actores. Estos se hallan agrupados en diferentes núcleos familiares procedentes de las regiones de Valaquia, Moldavia y Transilvania, y que hoy participan de una experiencia migratoria trans-nacional.Resultados: Se trata de una investigación iniciada en 2013 y que se encuentra en curso, por lo que los resultados son provisionales. En el caso de la minoría romaní se observa una notable discriminación por parte de los Estados, que produce una injustificada alarma social. En relación con el delito y la prostitución trans-nacionales, las políticas de control social tienden al pánico moral y se concentran en grupos delictivos de baja intensidad, buscando la permanente legitimación en una lucha simbólica (e ineficaz) frente a los fantasmas del “crimen organizado”.Discusión: El paradigma de la victimización criminalizadora contribuye a ahondar en el proceso de estigmatización de estas poblaciones, cuya esperanza emancipadora pasa necesariamente por des-afiliarse de los discursos dominantes. No obstante, evidenciar el carácter heterogéneo de las migraciones rumanas no debe llevarnos a ignorar la influencia de las estructuras socio-políticas ni el peso de la historia. Introduction: This article proposes a socio-ethnographic approach to those groups of the Romanian migratory movement that are reduced to living "on the Margins" and strategically and symbolically located "on the other side", that is, outside the law, society and the attention of the social sciences. Therefore, we will focus on the brigadas, youth groups that organise their activities around property crime and transnational prostitution; and the Roma clans, groups with family ties that survive through the collection and sale of scrap, seasonal agriculture or begging.Method: The biographical approach is based on the "Multi-sited" Ethnography (Spain / Romania), with special emphasis on the building of close and personal relationships with the participants. These are grouped in different family nuclei originated from the regions of Valaquia, Moldavia and Transilvania, and that today participate in a trans-national migratory experience.Results: This research was initiated in 2013 and is still in progress, so the results are provisional. In the case of the Roma minority, there is a considerable discrimination on the part of the state, which feeds an unjustified social alarm. In relation to trans-national crime and prostitution, the social control policies are driven by moral panic and concentrate on low-intensity criminal groups, seeking a permanent legitimisation of a symbolic (and ineffective) struggle against the ghosts of "organised crime".Discussion: The paradigm of criminalising victimisation contributes to deepening the process of stigmatisation of these populations, whose emancipatory hope requires an escape from the dominant discourses. However, illustrating the diversity of the Romanian migrations should not lead us to ignore the influence of socio-political structures or the weight of history.

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Tudoroiu, Theodor. "Transit Migration and “Valve States”." Southeastern Europe 41, no. 3 (2017): 302–32. http://dx.doi.org/10.1163/18763332-04103002.

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This article introduces the concept of a “valve” state as an instrument in the study of transit migration. A “valve” state is defined as a transit state that, due to its geographical position, to a specific regional political and geopolitical configuration and to key changes in its migration control policies, can play a decisive role in significantly shaping regional transit migratory flows. The case study of the 2015 Balkan migratory wave is used to show that this phenomenon was triggered by policy changes in two “valve” states, Greece and Macedonia, that challenged the externalisation and securitisation policies of the European Union. Developments in the first part of 2016 are also taken into consideration in order to show the role of “valve” states in putting an end to the migratory wave. Critically, this was due to the creation of a new “valve” state, Turkey, as part of Brussels’ regime of influence.

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Faret, Laurent, María Eugenia Anguiano Téllez, and Luz Helena Rodríguez-Tapia. "Migration Management and Changes in Mobility Patterns in the North and Central American Region." Journal on Migration and Human Security 9, no. 2 (2021): 63–79. http://dx.doi.org/10.1177/23315024211008096.

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Since the beginning of the twenty-first century, changes have occurred in the regional dynamics of international migration and in the ways governments manage human mobility. This article argues that the migratory system connecting the three northern countries of Central America (Guatemala, El Salvador, and Honduras) with Mexico and the United States has not been accompanied by regional management of migratory flows. Instead, a succession of government plans and projects reveals a perspective marked by the effects of the “externalization” of US borders, leading to more complex migration routes and increased vulnerability of migrants. The article discusses how externalized control policies influence migratory spaces, routes, and timelines, and leave many stranded in transit countries before they eventually arrive at their intended destinations. Reconsidering the process of mobility in light of migration management policies would appropriately enlarge the traditional economic, social, cultural, and environmental factors that affect migration strategies.

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Buess, Martin, Daniela A. Ferraro, Francesca Patella, Sara Zanivan, and Gerhard Christofori. "NIDOGEN1 as a novel regulator of endothelial control over breast cancer invasion and metastasis." Journal of Clinical Oncology 35, no. 15_suppl (2017): e23005-e23005. http://dx.doi.org/10.1200/jco.2017.35.15_suppl.e23005.

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e23005 Background: The microenvironment is a central regulator of cancer biology. While the contribution of fibroblasts has been largely studied, the role of endothelial cells as regulators of cancer cell behavior is still poorly understood. As in a diverse spectrum of physiological processes in normal tissue, endothelial cells may exert a similar regulatory control in cancer progression and metastasis. Methods: To characterize the functional effects of endothelial-cancer interaction we focused on an in vitro co-culture model. Results: Co-culturing human umbilical venous endothelial cells (HUVEC) with SKBR-3 breast cancer cells induced morphological changes with epithelial-mesenchymal transition traits (EMT) and a significantly increased migratory and invasive potential. This activity leading to an elongated phenotype, expression of mesenchymal markers and pro-migratory gene sets in SKBR-3 was contained in HUVEC conditioned medium. The pro-migratory effect on SKBR-3 was significantly more pronounced when the supernatant was obtained from a sub-confluent and highly proliferative endothelial cell culture than from a confluent and resting endothelial cell layer. To identify the secreted regulatory molecules, we analyzed the supernatant of sub-confluent and confluent endothelial cells by quantitative MS proteomics (SILAC analysis). Eight candidate proteins significantly more secreted in conditioned medium from confluent HUVEC represented potential inhibitors of migration. Among them NIDOGEN1 was found to be necessary and sufficient for the inhibition of EMT and migration in SKBR-3. Stimulation of SKBR-3 with supernatant from sub-confluent HUVEC increased p-STAT3 levels in SKBR-3. Silencing nidogen1 in confluent HUVEC re-activated phosphorylation of STAT3 indicating that NIDOGEN1 inhibits the promigratory STAT3 pathway. The STAT3 pathway and migration were also inhibited by overexpression of nidogen1 in MDA-MB-231 LM2 cells.When injected in the mammary fat pad of nude mice these cells formed significantly less lung metastases than controls (p < 0.01). Conclusions: We identified NIDOGEN1 as a novel regulator of endothelial control over cancer cell migration, invasion and metastasis.

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Cormier, Renée L., Diana L. Humple, Thomas Gardali, and Nathaniel E. Seavy. "Migratory connectivity of Golden-crowned Sparrows from two wintering regions in California." Animal Migration 3, no. 1 (2016): 48–56. http://dx.doi.org/10.1515/ami-2016-0005.

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AbstractKnowledge of migratory connectivity is critical to understanding the consequences of habitat loss and climate change on migratory species. We used light-level geolocators to determine breeding locations and migratory routes of wintering Golden-crowned Sparrows (Zonotrichia atricapilla) in two regions of California, USA. Eight out of 9 birds tagged at coastal-wintering sites in Marin County went to breeding sites along the Gulf Coast of Alaska, while 7 out of 8 inland-wintering birds in Placer County migrated to interior sites in the Yukon, Northwest Territories, and British Columbia, Canada. Our estimate of the strength of migratory connectivity was relatively high (rm = 0.66). Coastal-wintering birds followed a coastal migration route while inland-wintering birds migrated inland. Coastalwintering birds migrated significantly farther than inland birds (3,624 km versus 2,442 km). Coastal birds traveled at a greater rate during spring migration (179 km/d) than did inland birds (118 km/d), but there was no statistical difference in the rate of fall migration (167 km/d and 111 km/d, respectively). Dates of arrival and departure, and duration of spring and fall migration, did not differ between groups, nor did return rates. Rates of return also did not differ between tagged and control birds. The distinct migration routes and breeding areas suggests that there may be more structuring in the migratory geography of the Golden-crowned Sparrow than in a simple panmictic population.

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Bowlin, Melissa S. "Sex, Wingtip Shape, and Wing-Loading Predict Arrival Date at a Stopover Site in the Swainson's Thrush (Catharus Ustulatus)." Auk 124, no. 4 (2007): 1388–96. http://dx.doi.org/10.1093/auk/124.4.1388.

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Abstract Pointed wingtips and low wing-loading are believed to reduce the amount of energy used during migratory flight. If this is true, individuals with pointed wingtips or consistently low wing-loading should be able to migrate faster than conspecifics and may arrive on the breeding grounds and at stopover sites earlier. To test this hypothesis, I captured 97 Swainson's Thrushes (Catharus ustulatus; hereafter “thrushes”) during May in three consecutive field seasons, 2003-2005, at a stopover site in central Illinois. I used molecular techniques to sex 47 of these thrushes and created a discriminant function analysis using wing, tarsometatarsus, and tail lengths that predicted sex with 80.9% accuracy (P < 0.001). I applied this function to the remaining 50 thrushes so that I could control for any sexual dimorphism in morphology and arrival timing, and then examined seasonal trends in sex and morphology. Male thrushes arrived earlier at my stopover site than females (P < 0.001). After controlling for sex, thrushes with more pointed wingtips (P = 0.002) and lower wing-loading (P = 0.044) arrived earlier than thrushes with more rounded wingtips and higher wing-loading. The general linear model with sex, wingtip pointedness, and wing-loading explained nearly one-third of the variation in arrival date (P < 0.001, r2 = 0.281, n = 90). Pointed wingtips and lower wing-loading may help migratory birds cover distance more quickly and arrive at the breeding grounds sooner; alternatively, thrushes with more pointed wingtips and lower wing-loading may have departed from the wintering grounds earlier. If wing shape and size affect rate of migration, these variables may be important determinants of individual quality in migratory passerines. El Sexo, la Forma de las Puntas de las Alas y la Carga Alar Predicen la Fecha de Arribo de Catharus ustulatus a un Sitio de Escala Migratoria

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Ong, David M. "Joint Development of Common Offshore oil and Gas Deposits: “Mere” State Practice or Customary International Law?" American Journal of International Law 93, no. 4 (1999): 771–804. http://dx.doi.org/10.2307/2555344.

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The entry into force of the 1982 United Nations Convention on the Law of the Sea1 and its widespread ratification2 have renewed interest in the remaining gaps and ambiguities in its provisions on the control of shared marine resources. The discussion has recently focused on die regulation of common or transboundary fishing stocks3 and migratory species,4 a problem that was considered serious enough to merit the adoption of another multilateral convention. The 1995 Agreement on the Conservation and Management of Straddling Fish Stocks and Highly Migratory Fish Stocks5 was designed to resolve the increasing number of disputes on this issue.6

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Ramsay, Alan G., Lena Svensson, Nancy Hogg, and John G. Gribben. "Defective T Cell Migration in Chronic Lymphocytic Leukemia Is Repaired by Lenalidomide." Blood 112, no. 11 (2008): 3117. http://dx.doi.org/10.1182/blood.v112.11.3117.3117.

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Abstract We have previously demonstrated that multiple gene expression abnormalities are induced in T cells from chronic lymphocytic leukemia (CLL) patients including defects within the actin cytoskeleton signaling pathways that control immune recognition and motility (Gullu et al. JCI, 2005). T cell immune surveillance requires rapid migratory responses and LFA-1 (CD11a/CD18; αLβ2) is a promigratory receptor that engages the cytoskeleton to control migration. We hypothesized that CLL T cells may exhibit dysfunctional migration in response to ICAM-1, the principal ligand for LFA-1. Using time lapse microscopy, we observed significantly reduced chemokine SDF-1 (CXCL12) induced migration on ICAM-1 of CLL CD4 and CD8 T cells compared to age-matched healthy donor T cells. Healthy T cells tracked for 45 min displayed a random course of migration with an average speed of ~ 8 μm/min, whereas CLL T cells were slower ~ 5 μm/min (n=14, ~ 30% reduction, p&lt;0.01). We further postulated that direct contact of CLL tumor cells with healthy T cells would induce this migratory defect. Healthy CD4 or CD8 T cells were cocultured with either allogeneic CLL B cells or allogeneic healthy B cells and subsequently used in migration assays. Co-culture with CLL cells resulted in significantly reduced T cell migration compared with co-culture with healthy B cells (~ 44% reduction in migration, n=6, p&lt;0.01). Evidence that direct contact was required to induce this migratory defect was shown when no effect was observed when cell-cell adhesion was prevented by pretreatment of CLL cells with anti-ICAM-1 blocking antibody prior to primary co-culture with healthy T cells. This cancer-induced migratory defect was repaired when CLL T cells were pretreated with the immunomodulatory drug Lenalidomide (1μM for 1hr). Treatment with this agent enhanced the migratory potential of CLL T cells to a speed comparable to untreated and treated healthy T cells. The finding that lenalidomide can restore rapid migration in patient T cells provides evidence that this agent may increase immune surveillance in CLL patients.

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Journal articles on the topic 'Migratory Control'

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