Investigation of cross-reactivity between commercially available antibodies directed against human, mouse, and rat lymphocyte surface antigens and surface markers on canine cells.

Using automated flow cytometry, 23 commercially available antibodies (all but one of them monoclonal) raised against surface antigens of specific populations of human, rat, and mouse lymphocytes were tested for cross-reactivity to peripheral blood lymphocytes from five clinically healthy adult dogs. Of all the antibodies tested, only the polyclonal anti-asialo GM1 directed against mouse NK cells, and the monoclonal antibodies anti-HLA-DR directed against the human class II antigen and anti-B1, a human pan B cell marker, consistently labeled subpopulations of canine lymphocytes.