Expression of intercellular adhesion molecule 1 (ICAM-1) on the human oviductal epithelium and mediation lymphoid cell adherence

The epithelium of the human oviduct expresses the major histocompatibility complex (MHC) class II and shows endocytic properties towards luminal antig ens. Therefore, the epithelial cells might behave as antigen-presenting cel ls, inducing a local immune response. The activation of antigen-specific T cells not only requires presentation of the peptide antigen by MHC class II , but also the presence of co-stimulatory molecules in the antigen-presenti ng cells. Therefore, the expression of the intercellular adhesion molecule 1 (ICAM-1) was examined in the epithelium of the human oviduct. Most oviduc ts showed epithelial ICAM-1 expression, as assessed by immunocytochemistry, western blot analysis and RT-PCR assay, and the expression was restricted to the luminal border of ciliated and secretory cells. Interferon gamma, in terleukin 1 and lipopolysaccharide treatments increased the percentage of I CAM-1-positive cells in primary cultures, indicating that the expression of ICAM-1 in the oviduct might be upregulated in vivo by inflammatory cytokin es or bacterial infections. Binding assays between allogenic phytohaemagglu tinin-activated lymphocytes and epithelial monolayers expressing ICAM-1 dem onstrated that this molecule stimulated lymphocyte adherence. The presence of ICAM-1, in addition to MHC class II, supports the putative role of the o viductal epithelium in antigen presentation. The exclusive apical distribut ion of ICAM-1 indicates that T-cell activation would occur in a polarized m anner. Binding of lymphoid cells to the surface of the oviductal epithelium may help to retain these immune cells that are required for the clearance of pathogens.