The organ distribution of gp-330 (Heymann antigen) and gp-90 in the mouse and the rat.

The Heymann antigen (gp-330) and an antigen with lower molecular weight (gp-90) are major constituents of the brush border of the renal proximal tubules in the rat and the mouse. The Heymann antigen can also be found at discrete sites in the glomerular visceral epithelium of the rat, but not of the mouse. Gp-90 is present diffusely along the glomerular capillary wall of rat and mouse. The Heymann antigen is probably the target antigen for membranous glomerulonephritis in the rat, while in the mouse, where this form of glomerulonephritis can also be induced, gp-90 seems to be the antigen involved. We have separated the antibody populations against these two antigens by preparing eluates from kidneys of rats and livers of mice that had been injected with an antiserum against pronase-digested mouse renal tubular antigens. Using these purified antibodies we have examined by indirect immunofluorescence the distribution of the two antigens on normal mouse and rat tissues. The expression of the Heymann antigen is limited to the epithelia of several organs, while gp-90 has a more widespread distribution in many cells of different origin and function in both the mouse and the rat.