Antiphospholipid antibodies reactive with bromelain-treated mouse erythrocytes in mice, rats and rabbits.

It has been reported that normal mice have a large number of B cells against bromelain-treated mouse erythrocytes (BrMRBC) and the anti-BrMRBC antibodies are reactive with liposomes of phosphatidylcholine and a phospholipid moiety of low-density lipoproteins from chicken egg yolk (EyLDL). In this study, we detected anti-BrMRBC hemolytic antibodies in the normal sera of rats and rabbits as well as mice. The antibodies in all the three species of animals bound to the columns of EyLDL. The EyLDL-binding antibodies could react with both liposomes of phosphatidylcholine and BrMRBC. The immunization with EyLDL evoked a vast production of anti-BrMRBC antibodies in rats and rabbits as well as mice. The anti-BrMRBC antibodies in the immunized animals could also react with liposomes of phosphatidylcholine. These findings suggest that rats and rabbits have the equivalent of mouse anti-BrMRBC B cells.