Positive selection of dendritic epidermal gammadelta T cell precursors in the fetal thymus determines expression of skin-homing receptors.
The role of cellular selection in the development of gammadelta T cells remains unclear. Knockout mice lacking a subset of Vgamma genes, including Vgamma3, contain abundant gammadelta T cells but are devoid of dendritic epidermal gammadeltaT cells (DETCs), which normally express an invariant Vgamma3/Vdelta1 gammadelta TCR. A rearranged Vgamma2 transgene restored DETC development, but the restored DETCs selectively expressed a unique Vdelta gene other than Vdelta1, indicating that DETC development involves TCR-based selection. In both normal and transgenic/knockout mice, specific DETC precursors in the fetal thymus were activated and expressed the IL-15 receptor beta chain, skin-homing receptors, and thymic exiting receptors. In vitro activation of irrelevant precursors also led to upregulation of the skin-homing receptor, providing an explanation for how thymic selection is coordinated with development of epidermal gammadelta T cells.
Xiong
Na
N
Department of Molecular and Cell Biology, 489 Life Sciences Addition, University of California, Berkeley, 94720, USA.
Kang
Chuhlo
C
Raulet
David H
DH
D000818:Animals; D003713:Dendritic Cells / Q000378:metabolism*; D006412:Hematopoietic Stem Cells / Q000502:physiology; D051379:Mice; D018345:Mice, Knockout; D008822:Mice, Transgenic; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000378:metabolism*; D053647:Receptors, Interleukin-15; D015375:Receptors, Interleukin-2 / Q000378:metabolism; D016201:Receptors, Lymphocyte Homing / Q000378:metabolism*; D012867:Skin / Q000166:cytology; D013601:T-Lymphocytes; D013950:Thymus Gland / Q000166:cytology* / Q000196:embryology
C508025:Il15ra protein, mouse; D016692:Receptors, Antigen, T-Cell, gamma-delta; D053647:Receptors, Interleukin-15; D015375:Receptors, Interleukin-2; D016201:Receptors, Lymphocyte Homing