Immunohistochemical demonstration of H2 antigens in mouse tissue sections

The immunohistological demonstration of H2 antigens in cryostat sections of a wide variety of mouse tissues is reported. The purpose in developing the method was to use H2 antigens as cellular markers in studies of mouse chimeras. Monoclonal anti-H2 antibodies were used, either with a hapten-sandwich technique using biotin or arsanilate, or as direct enzyme conjugates. The direct antibody-enzyme conjugates were simpler to use, provided an intensity of specific staining which was comparable to that obtained with the hapten-sandwich systems, and gave fewer problems of background when simultaneous double staining was attempted. The results provide a description of the distribution of H2 antigens in many of these tissues. The intensity of H2 staining varied widely from tissue to tissue, but also within tissues and between individual mice of the same litter. Quantitation by autoradiography suggests that there is a fivefold variation in available H2 antigen between tissues which are stained strongly or weakly by our technique.