IgG antibodies produced by heterozygous a1a3 rabbits responding to acidic azohaptens are predominantly of allotype a1
Chien, C.C.; Ingraham, J.S.
Journal of Immunology 121(4): 1341-1347
1978
ISSN/ISBN: 0022-1767 PMID: 359705 Document Number: 128063
Rabbits of allotype a1a3 were immunized with 1 of 3 acidic hapten-bovine serum albumin (BSA) conjugates: p-azophenyl arsonate (AA)-, p-azophenyl sulfonate (SA)- or p-azobenzoate (CA [p-azophenyl carboxylate])-BSA; all animals received the basic conjugate, p-azophenyl-N-trimethylammonium (TMA)-BSA. After 6-12 mo., each animal was challenged with the same combination of BSA conjugates as given originally. The allotype of the plaque-forming cells (PFC) from lymph nodes and spleen was determined by enhancement with anti-allotype antisera. PFC detected upon addition of anti-a1 were designated a1-PFC and those detected with anti-a3 were designated a3-PFC. Results were expressed as the ratio of a1-PFC to a3-PFC. For the basic hapten, TMA, this ratio was 0.2-1.0 for 9 lymph nodes and 0.3-1.6 for 7 spleens. The ratio for the acidic haptens was much higher: for AA, from 4-16 in 3 lymph nodes and 24-87 in 2 spleens; for SA, from 4-114 in 3 nodes and 38-59 in 2 spleens; for CA from 13-130 in 2 nodes and 4-33 in 3 spleens. Analogous use of anti-allotype sera for enhancement of anti-acidic hapten hemolytic serum titers showed that anti-a1 gave 8-16 times the enhancement given with anti-a3. The results indicate that the a1a3 rabbits made little or no antibody of allotype a3 during the secondary response to these acid haptens.