[Chronic inflammation of mucous membranes: integration of immunity and regeneration]

Lymphoid tissue of mucous membranes is a morphological basis for local immunity. Lymphocytes of mucous membranes are bifunctional: reception of antigenic information and regulation of epithelial cells regeneration. The following structural manifestations of intercellular interactions are discussed: expression of HLA-DR antigens by the epithelium and endotheliocytes transforming them into "facultative" antigen-presenting cells; polyclonal plasmocyte proliferation; the exchange of their prevailing IgA phenotype for IgG; cytotoxic and cytogenetic effect of the interepithelial lymphocytes.