Distribution of H antigen in persons of blood groups A, B, and AB.

The distribution of H antigen in tissues of persons of blood groups A, B, and AB was examined. H antigen could be demonstrated in all tissues in which the isologous antigens A and B were demonstrated, although some cells demonstrated isologous but not H antigen. In most tissues, areas were seen that demonstrated H antigen but not the isologous antigen. This was especially true in Brunner's glands of the duodenum and esophageal glands, where the amount of H antigen was apparently greater than the amount of the isologous antigen. Since the results varied greatly from tissue to tissue, it was not possible to interpret the data with respect to the biochemical pathways of blood group antigen formation.