ADHESION MOLECULE EXPRESSION BY EPIDERMAL LANGERHANS CELLS AND LYMPH-NODE DENDRITIC CELLS - A COMPARISON

The migration of epidermal Langerhans cells (LC) and their transport o f antigen from the skin to draining lymph nodes are of considerable im portance in the induction of cutaneous immune responses, including con tact sensitization, While in transit to the lymph nodes, LC are subjec t to a number of phenotypic changes required for their movement from t he skin and acquisition of the capacity for antigen presentation, Amon g these are alterations in the expression of adhesion molecules that r egulate interactions with the surrounding tissue matrix and with T lym phocytes, In the study described here, we investigated, using a combin ation of immunocytochemistry and flow cytometry, the expression by LC, and the lymph node dendritic cells into which they mature, of the thr ee adhesion molecules, E-cadherin, intercellular adhesion molecule-1 ( ICAM-1) and the membrane glycoprotein CD44, The migration of LC was as sociated with a marked reduction in the expression of E-cadherin, but a parallel upregulation of ICAM-1, No change in the expression of CD44 was detectable, The significance of these changes and their relevance for the functional maturation of LC are discussed.