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1.  Ontogeny of the Immune System: γ/δ and α/β T Cells Migrate from Thymus to the Periphery in Alternating Waves  
The embryonic thymus is colonized by the influx of hemopoietic progenitors in waves. To characterize the T cell progeny of the initial colonization waves, we used intravenous adoptive transfer of bone marrow progenitors into congenic embryos. The experiments were performed in birds because intravenous cell infusions can be performed more efficiently in avian than in mammalian embryos. Progenitor cells, which entered the vascularized thymus via interlobular venules in the capsular region and capillaries located at the corticomedullary junction, homed to the outer cortex to begin thymocyte differentiation. The kinetics of differentiation and emigration of the T cell progeny were analyzed for the first three waves of progenitors. Each progenitor wave gave rise to γ/δ T cells 3 d earlier than α/β T cells. Although the flow of T cell migration from the thymus was uninterrupted, distinct colonization and differentiation kinetics defined three successive waves of γ/δ and α/β T cells that depart sequentially the thymus en route to the periphery. Each wave of precursors rearranged all three TCR Vγ gene families, but displayed a variable repertoire. The data indicate a complex pattern of repertoire diversification by the progeny of founder thymocyte progenitors.
PMCID: PMC2199063  PMID: 9314548
2.  Microbiology Study of a Hypersaline Lake in French Somaliland 
Applied Microbiology  1974;27(5):819-822.
In a study of a lake having a higher concentration of salts than the Dead Sea, all of the heterotrophic bacteria isolated were aerobes; no strictly anaerobic strains were found. Ninety percent of the strains were euryhalines and ten percent were strict halophiles. The extreme halophiles belonged to the species Halobacterium trapanicum and Halococcus morrhuae.
PMCID: PMC380149  PMID: 4833284

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