STUDIES OF THE CORYNEBACTERIUM PARVUM-ASSOCIATED ANAEMIA IN MICE.

The results suggest that the anaemia in mice associated with the injection of C. parvum is mediated by an immune mechanism. Survival studies of 51Cr-labelled red blood cells (RBC) in splenectomized and unsplenectomized mice show that mice immunized with C. parvum three times, clear RBC faster than unimmunized mice. However, hyperimmunized mice stabilized their haemoglobin concentrations above their minimum level and did not clear 51Cr-labelled RBC faster than unimmunized mice. All mice produced antibody against C. parvum but remained direct Coombs'-negative. Serum from immunized animals did not contain opsonins for -51Cr-labelled RBC. The reticulocytosis, normal osmotic fragility tests and normal survival times of 51Cr-labelled RBC from C. parvum-immunized mice all suggest that the main direct influence of the micro-organism is extrinsic of the RBC. Antigens from the micro-organism were adsorbed by erythrocytes in vitro. It is hypothesized that the anaemia is caused by destruction of RBC brought about by antibody reacting with bacteria that have been adsorbed by RBC. [ABSTRACT FROM AUTHOR]