T cell receptor specificity is critical for the development of epidermal gammadelta T cells.
A particular feature of gammadelta T cell biology is that cells expressing T cell receptor (TCR) using specific Vgamma/Vdelta segments are localized in distinct epithelial sites, e.g., in mouse epidermis nearly all gammadelta T cells express Vgamma3/Vdelta1. These cells, referred to as dendritic epidermal T cells (DETC) originate from fetal Vgamma3+ thymocytes. The role of gammadelta TCR specificity in DETC's migration/localization to the skin has remained controversial. To address this issue we have generated transgenic (Tg) mice expressing a TCR delta chain (Vdelta6.3-Ddelta1-Ddelta2-Jdelta1-Cdelta), which can pair with Vgamma3 in fetal thymocytes but is not normally expressed by DETC. In wild-type (wt) Vdelta6.3Tg mice DETC were present and virtually all of them express Vdelta6.3. However, DETC were absent in TCR-delta(-/-) Vdelta6.3Tg mice, despite the fact that Vdelta6.3Tg gammadelta T cells were present in normal numbers in other lymphoid and nonlymphoid tissues. In wt Vdelta6.3Tg mice, a high proportion of in-frame Vdelta1 transcripts were found in DETC, suggesting that the expression of an endogenous TCR-delta (most probably Vdelta1) was required for the development of Vdelta6.3+ epidermal gammadelta T cells. Collectively our data demonstrate that TCR specificity is essential for the development of gammadelta T cells in the epidermis. Moreover, they show that the TCR-delta locus is not allelically excluded.
Ferrero
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I
Ludwig Institute for Cancer Research, Lausanne Branch, University of Lausanne, CH-1066 Epalinges, Switzerland.
Wilson
A
A
Beermann
F
F
Held
W
W
MacDonald
H R
HR
D000818:Animals; D002465:Cell Movement; D003713:Dendritic Cells / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000235:genetics / Q000502:physiology*; D012867:Skin / Q000276:immunology*; D013234:Stem Cells / Q000502:physiology; D013601:T-Lymphocytes / Q000502:physiology*; D013950:Thymus Gland / Q000166:cytology
D016692:Receptors, Antigen, T-Cell, gamma-delta