Abstract: | Epidermal dendritic cells (Langerhans cells) present cutaneously derived antigens to T cells in the skin and draining lymph nodes and therefore are important in many afferent immune responses. The role of dermal dendritic cells on the other hand is more obscure, although it has been suggested that these cells are precursor forms of Langerhans cells. Although human cutaneous dendritic cells have been previously characterized by using monoclonal antibodies, there are no reports of comparable studies in the skin of rhesus monkeys. By using an immunoperoxidase technique with light and immunoelectron microscopy, we have evaluated 29 antibodies raised against human cell surface antigens for their reactivity to dendritic cells in the skin of rhesus monkeys. This study demonstrates that many antisera to human cell surface antigens can be used to identify cutaneous dendritic cells in this species and that the cell populations so labeled are similar ultrastructurally to those in man. These observations represent the first demonstration of immunologic markers specific for epidermal Langerhans cells in animals, and are requisite for further study of dendritic cell function in nonhuman primate models of human immunopathologic diseases. |