Allo-aggression in chickens. II. Cellular expression of the AA gene products

B1-anti-B2 and B2-anti-B1 allo-antisera were raised by i.v. immunization of homozygous B1/1 and B2/2 chickens, respectively, with B1/2 cells of the following sources: peripheral blood leucocytes (PBL), erythrocytes, thymus cells and bursa cells. Purified suspensions of these all produced anti-B allo-antibodies which could both haemagglutinate red blood cells and strongly inhibit the GVH reactivity of blood lymphocytes of the original donor type. Absorption studies of the sera using cells of the same four sources showed that they could all completely remove the GVH inhibitory antibodies. A fact of particular importance is that B-haplotype determined antigens which are common to erythrocytes and lymphocytes seem to include the gene products of the allo-aggression locus, as earlier defined (Simonsen 1975).