The detection and production of macrophage cytophilic antibody to different antigens in different laboratory animals.

An assay for macrophage cytophilic antibody is described, based on the measurement of the adherence of I-labelled antigen to peritoneal exudate cells pretreated with antiserum. Using this assay, the production of cytophilic antibody to SRBC, BSA, polymerized flagellin, flagellin and a CNBr digest of flagellin was investigated in guinea-pigs, rats, rabbits and mice. Antigens injected in either Freund's complete or incomplete adjuvant were almost equally efficient at inducing cytophilic antibody production. In contrast, antigens injected in saline failed to induce detectable cytophilic antibody. The ratio of cytophilic antibody titre/passive haemagglutinating antibody titre was calculated and it was found that the ratio for rabbit>guinea-pig>mouse>rat. Furthermore, in those sera which were examined, cytophilic antibody was only detected in the 7S fractions.