Interleukin-10 enhances gamma delta T cell development in the murine fetal thymus

We have investigated the ability of interleukin-10 (IL-10) to modulate murine intrathymic T cell differentiation using a fetal thymic organ culture (FTOC) model. Addition of as little as 11 ng of recombinant murine IL-10 (mIL-10) per day produced a significant increase in the proportion and number of gamma delta-TCR+ cells in 4-day cultures derived from Gestational Day 14 mice, compared to vehicle-treated cultures. This effect occurred in the absence of any changes in other parameters of intrathymic T cell development. The increase in the gamma delta-TCR population included an enlargement of the V gamma 2+, V gamma 3+, and V delta 4+ populations. The enhancement of gamma delta cell development was not observed in 2- or 7-day cultures, indicating the time dependence of this response. Overall, these results reveal that IL-10 treatment of FTOC can affect murine gamma delta T cell development and suggest that this cytokine may mediate specific events in the generation of the gamma delta T cell repertoire.