Association between circulating immune complexes and renal disease in New Zealand mice.

Using female NZB x NZW (B/W) F1 x NZW backcross mice, analyses were made to determine the correlations among C1q- binding and conglutinin (Kg) binding immune complexes in the circulation and the proteinuria of the B/W F1 mice. There was a significant association between the development of proteinuria and the high serum level of Kg-binding immune complexes, while no significant association was seen between the proteinuria and the C1q-binding immune complexes in the backcrosses. There was a lack of correlation between these C1q-binding and Kg-binding immune complexes. These results suggest that the major immune complexes detected by these two methods differ in nature and emphasize that the demonstration of antigen-non-specific immune complexes in the circulation do not necessarily mean that these immune complexes are responsible for the pathogenesis of the particular disease being studied.