Expression of the mucosal T cell integrin αM290β7 by a major subpopulation of dendritic cells in mice

Dendritic interdigitating cells isolated from lymph nodes, Langerhans' cells from skin and dendritic cells from the spleen have been tested for expression of the mucosal T cell integrin alpha M290 beta 7. Almost all interdigitating cells isolated from mesenteric lymph nodes expressed the integrin at high levels; 50-60% of those from lymph nodes draining non-mucosal sites also expressed this adhesion molecule. In contrast, alpha M290 beta 7 was not detected on either Langerhans' cells or splenic dendritic cells. Because this integrin has recently been shown to recognize a ligand that seems to be expressed mainly or exclusively by epithelial cells; it is proposed that this adhesion pathway may be important for antigen sampling by dendritic cells in mucosal tissues.