COMPARATIVE-ANALYSIS OF CD80 AND CD86 ON HUMAN LANGERHANS CELLS - EXPRESSION AND FUNCTION

Although both CD80 (B7-1) and CD86 (B7-2/B70) have been recently ident ified in cultured human Langerhans cells (LC), little is known of the role and regulatory properties of CD80 and CD86 on human LC. We presen t here the results of a study comparing the expression and function of CD80 and CD86 in human LC using the T-helper type-1 cytokines IL-2 an d interferon gamma (IFN)- gamma, and the T-helper type-2 cytokines IL- 10, IL-4 and granulocyte/macrophage colony-stimulating factor (GM-CSF) , Freshly isolated human LC expressed little CD80 and CD86 in vitro, b ut the expression of both molecules was rapidly induced during a 72-h incubation with cytokines and the expression of CD86 occurred much ear lier and more strongly than that of CD80. The expression of both CD80 and CD86 was upregulated by GM-CSF and downregulated by IL-10, and the expression of CD86, but not that of CD80, was upregulated by both IL- 4 and IFN-gamma, Finally, pretreatment of LC with GMCSF and IFN-gamma, but not with IL-4, enhanced the alloreactive T-cell proliferation ind uced by the LC, and IL-10 pretreatment of LC decreased their capacity for alloreaction, These results indicate that the expression of both C D80 and CD86 on human LC may be regulated by these cytokines (IL-2, IL -4, GM-CSF, IFN-gamma and IL-10) secreted from helper T cells infiltra ting into the inflammatory microenvironment.