Department of Dermatology, Allergy, and Venereology, University of Lübeck, Lübeck, Germany.
Lübeck Institute of Experimental Dermatology, University of Lübeck, Lübeck, Germany.
Eur J Immunol. 2021 Jun;51(6):1390-1398. doi: 10.1002/eji.202048887. Epub 2021 Apr 4.
The G protein-coupled receptor 15 (GPR15) regulates homing of different T-cell populations into the gut, thus, preserving tissue homeostasis. Its potential role in the preservation of homeostasis on other body interfaces, including the skin, is less well understood. We addressed the impact of GPR15 on cutaneous T-cell populations and the skin microbiome under steady-state conditions. Genetic deficiency in GPR15 substantially altered the composition of skin-resident T-cell populations. Precisely, dendritic epidermal T cells were almost absent in the epidermis of Gpr15 mice. The niche of dendritic epidermal T cells in the epidermis was, instead, populated by αβ TCR T cells. These changes were associated with shifts in the skin microbiota in Gpr15 mice. Collectively, our results uncover a role of GPR15 in the regulation of the cutaneous immune system and, thus, highlight the receptor as important general regulator of tissue homeostasis of exterior body interfaces.
G 蛋白偶联受体 15（GPR15）调节不同 T 细胞群向肠道的归巢，从而维持组织内稳态。其在维持其他身体界面（包括皮肤）内稳态方面的潜在作用尚未得到充分理解。我们研究了 GPR15 对皮肤 T 细胞群和皮肤微生物组在稳态条件下的影响。GPR15 的基因缺失显著改变了皮肤驻留 T 细胞群的组成。具体来说，Gpr15 小鼠的表皮中几乎不存在树突状表皮 T 细胞。取而代之的是，αβTCR T 细胞占据了树突状表皮 T 细胞在表皮中的生态位。这些变化与 Gpr15 小鼠皮肤微生物组的变化有关。总的来说，我们的结果揭示了 GPR15 在调节皮肤免疫系统中的作用，因此强调了该受体作为外部身体界面组织内稳态的重要普遍调节剂的作用。
