Abstract
Developing thymocytes are selected for recognition of molecules encoded by the major histocompatibility complex, purged of self-reactive cells and committed to either the CD4 or CD8 lineage. The 1% of thymocytes that complete these tasks emigrate and join the population of peripheral lymphocytes. Whether T cell maturation is complete at the time of thymic exit has been a subject of debate. Using mice transgenic for green fluorescent protein driven by the recombination activating gene 2 promoter to identify recent thymic emigrants, we now show that T cell differentiation continues post-thymically, with progressive maturation of both surface phenotype and immune function. In addition, the relative contribution of CD4 and CD8 recent thymic emigrants was modulated as they entered the peripheral T cell pool. Thus, T cell maturation and subset contribution are both finalized in the lymphoid periphery.
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Acknowledgements
Supported by National Institutes of Health grants AG13078 and AI44130 and a pilot grant from the Nathan Shock Center for Excellence in the Basic Biology of Aging (P.J.F.), F32 CA84736 (T.E.B.) and T32 AI07411 (C.J.C.).
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Boursalian, T., Golob, J., Soper, D. et al. Continued maturation of thymic emigrants in the periphery. Nat Immunol 5, 418–425 (2004). https://doi.org/10.1038/ni1049
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DOI: https://doi.org/10.1038/ni1049
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