The role of dendritic cells in the initiation of immune responses to contact sensitizers. II. Studies in nude mice.

Twenty-four hours after skin painting nude mice with picryl chloride, there was an increase in the number of dendritic cells (DC) isolated from the draining lymph nodes. This increased inflow or retention of DC in lymph nodes following skin painting is therefore unlikely to depend on interaction of DC with T cells. The DC obtained initiated primary proliferative responses in vitro in lymph node cells from congenic euthymic mice. Contact sensitivity developed in congenic mice when they received footpad injections of 60,000 DC from the lymph nodes of nude mice skin sensitized 1 day previously with picryl chloride or oxazolone. The initiation of delayed hypersensitivity was therefore independent of T-cell contamination within the donor DC.