As an immune privilege site, there are various types of immune cells in the testis. Previous research has been focused on the testicular macrophages, and much less is known about the T cells in the testis. Here, we found that T cells with memory phenotypes were the most abundant leukocyte in the testis except for macrophages. Our results showed that the proportion of testicular T cells increases gradually from birth to adulthood in mice and that the primary type of T cells changed from γδTCR+ T cells to αβTCR+ T cells. In addition, under homeostatic conditions, CD8+ T cells are the dominant subgroup and have different phenotypic characteristics from CD4+ T cells. We found that cDC1, but not cDC2, is necessary for the presence of T cells in the testis under physiological state. A significant decrease of T cells does not have a deleterious effect on the development of the testis or spermatogenesis. However, cDC1-dependent T cells play an indispensable role in chronic autoimmune orchitis of the testis. Collectively, our multifaceted data provide a comprehensive picture of the accumulation, localization, and function of testicular T cells.
Keywords: T cells; chronic autoimmune orchitis; dendritic cell; spermatogenesis; testis.
Copyright © 2021 Jing, Cao, Zhang, Long and Wang.