Analysis of the mechanism of the restricted localization of Vγ3 T cells in the epidermis

小鼠皮肤的上皮内T细胞，称为树突状表皮T细胞（DETC），仅表达不变的（V γ 3-J γ 1/V δ 1-D δ 2-J δ 2）γ δ TCR。胎儿胸腺的DETC前体细胞在出生前就迁移到皮肤上，成年小鼠中表达与DETC相同的经典V γ 3 TCR的T细胞在其他淋巴组织或上皮组织中未发现。这项研究表明，DETC前体在胎儿时期迁移到肠道和皮肤，但出生后优先在皮肤中存活和扩张。由于V γ 3 TCR的配体仅在皮肤中表达，因此在识别自身配体后，同质表皮γ δ T细胞库的"外周选择"可能由V γ 3 TCR信号传导介导。

Intraepithelial T cells of the murine skin, called dendritic epidermal T cells (DETC), express exclusively an invariant (Vγ3-Jγ1/Vδ1-Dδ2-Jδ2)γδ TCR. Fetal thymic precursors of DETC immigrate to the skin before birth, and in adult mice T cells expressing the canonical Vγ3 TCR identical to that of DETC are not found in other lymphoid or epithelial tissues. This study showed that DETC precursors migrate to the gut as well as to the skin during fetal periods, but preferentially survive and expand in the skin after birth. Because the ligand for the Vγ3 TCR was expressed only in the skin, "peripheral selection" of the homogeneous epidermal γδ T cell repertoire may be mediated by Vγ3 TCR signaling upon the recognition of the self-ligand.