Heterophile antibodies. Part III. Evidence for linkage of high responder activity to sheep red blood cells and the formation of specific antibodies to HBsAg.
Group A, B and O subjects who produce immune antibodies to group A1 or B red blood cells also produce high titer antibodies to sheep red blood cells. Sheep red blood cells appear to possess AB-like as well as non-AB determinants on their surface membranes, each capable of producing and reacting with antibodies of their respective specificities. The antibodies against AB-like determinants preferentially agglutinate A or B cells whereas non-AB-like determinants preferentially stimulate hemolytic antibodies. Human antibodies reacting with these two kinds of determinants on sheep red blood cells may be produced in response to microorganisms possessing very similar factors on their membranes. Individuals who possess AB-like determinants in their secretions, similar to the determinants present on sheep red blood cells (or microorganisms), often make weaker antibodies to these red blood cells. Subjects lacking corresponding anti-sheep inhibitors in their secretions generally produce stronger sheep red blood cell antibodies. There is a positive correlation between the formation of antibodies to HBsAg and strong agglutinating antibodies to sheep red blood cells, indicating that similar determinants may be found on HBsAg virus and on sheep red blood cells. No such correlation was found for anti-tetanus antibodies.