A question of persistence: Langerhans cells and graft-versus-host disease.

Langerhans cells ( LCs) have been scrutinized many times in studies of the pathogenesis of graft-versus-host disease ( GVHD). As migratory dendritic cells, LCs are capable of direct antigen presentation to cytotoxic T cells. Their self-renewal capacity has led to speculation that persistent recipient LCs could provide a continuous source of host antigen to donor T cells infused during hematopoietic stem cell transplantation ( HSCT). In this issue of Experimental Dermatology, a new study examines at the relationship between recipient LCs and chronic GVHD. [ABSTRACT FROM AUTHOR]