Dynamics of Langerhans cells in genetically defined murine epidermal cell culture

Abstract

Unlike keratinocytes, Langerhans cells [LC] express both surface ATPase activity and Ia (HLA-DR) antigens. A well-characterized in vitro system containing LC would be of great use in elucidating their functions. Epidermal cell cultures derived from neonatal Balb/c mice were examined for the presence of LC. Twenty-four hours after initiation of culture, ATPase- and Ia-positive cells were associated with cell aggregates. By day 3, LC migrated on to the substratum and, as the cultures matured and stratified, were seen both in groups and as single cells for the duration of the cultures (day 14). During culture, although the total number of cells increased, the percentage of cells expressing Ia antigen and ATPase activity remained constant, suggesting LC increase in number during cell culture. Such a situation could arise from actual division of LC during culture or from latent expression of Ia antigen and ATPase activity by pre-existing cells. This is the 1st study of the dynamics of LC in a cell culture system and shows that LC are present throughout the lifespan of the cultures.