Immunophenotypic characterization of hepatic inflammatory cell infiltrates in common dolphins (Delphinus delphis)

Abstract

Of 14 common dolphins, 12 showed non-specific reactive hepatitis and three chronic parasitic cholangitis with lymphoid proliferation. Non-specific reactive hepatitis was shown immunohistochemically to beassociated with small clusters of CD3+ cells in portal areas and hepatic sinusoids. Polyclonal antibody against S100 protein reacted with a variable number of lymphocytes from portal areas and hepaticsinusoids, as well as with Kupffer cells and epithelial cells of the bile ducts. The majority of plasma cells observed in portal areas and hepatic sinusoids were IgG+. In lymphonodular lesions of chronic parasiticcholangitis, the distribution of immunoreactive cells was similar to that found in the cortex of lymphnodes. The presence of stellate cells similar to follicular dendritic and interdigitating cells expressing S-100 protein and MHC class II antigen in lymphonodular lesions suggested that these were highly organized structures developed to enhance antigen presentation to B and T cells.