Attenuation of canine nephrotoxic glomerulonephritis with an extracorporeal immunoadsorbent

A novel immunoadsorbent is described in which soluble canine glomerular basement membrane (GBM) antigen was immobilized in collodion membranes adherent to small charcoal particles. As much as 80% of the added GBM antigen was retained in the collodion-charcoal. The binding of GBM antibody to immobilized GBM antigen in vitro and in vivo was demonstrated. For in vivo studies, an extracorporeal circulation system was established, and mongrel dogs were then injected intravenously with GBM collodion-charcoal for 4 h. Renal tissue was examined by fluorescence and light microscopy for the deposition of heterologous gamma globulin and glomerular inflammation before and after the extracorporeal procedure. Results showed less deposition of heterologous IgG and less inflammation in experimental dog kidneys than in control kidneys. There was no evidence of release of 131I-labeled GBM from the immunoadsorbent at the conclusion of perfusion experiments and no significant biochemical or hematologic alterations. Finally, extracorporeal immunoadsorbent treatment was capable of attenuating the early heterologous phase of passive canine nephrotoxic nephritis and may have a potential role in the therapy of anti-GBM-mediated nephropathy.