Vogt A, Rohrbach R, Shimizu F, Takamiya H, Batsford S
Kidney Int. 1982 Jul;22(1):27-35. doi: 10.1038/ki.1982.128.
The influence of charge and size on antigen binding to the rat glomerular basement membrane (GBM) was investigated. Chemically cationized ovalbumin, human serum albumin (HSA), human immunoglobulin G (Hu IgG), horse spleen ferritin and human immunoglobulin M (Hu IgM) were injected into rats intravenously. By immunofluorescence significant glomerular binding occurred when the pI exceeded a threshold value of 8.5 to 9.5. At a given pI antigen binding increased with molecular size. Cationized Hu IgM bound only weakly to the glomerular capillary wall, presumably excluded due to size. Subepithelial immune deposits were formed only when antibody was injected subsequently. Detailed electron microscopic studies on in situ formation of immune complexes were performed using cationized horse spleen ferritin. Early on subendothelial deposits were very marked, giving way to subepithelial deposits with time. Under the conditions employed, it appears that deposits can be formed directly at the subepithelial locus but that complexes are also formed subendothelially, dissociating into free molecules or small complexes and then migrating through the lamina densa and reforming.
研究了电荷和大小对抗原与大鼠肾小球基底膜（GBM）结合的影响。将化学阳离子化的卵清蛋白、人血清白蛋白（HSA）、人免疫球蛋白G（Hu IgG）、马脾铁蛋白和人免疫球蛋白M（Hu IgM）静脉注射到大鼠体内。通过免疫荧光法发现，当pI超过8.5至9.5的阈值时，肾小球出现明显的结合。在给定的pI下，抗原结合随分子大小增加。阳离子化的Hu IgM仅与肾小球毛细血管壁弱结合，可能由于大小原因而被排除。仅在随后注射抗体时才形成上皮下免疫沉积物。使用阳离子化的马脾铁蛋白对免疫复合物的原位形成进行了详细的电子显微镜研究。早期内皮下沉积物非常明显，随着时间的推移被上皮下沉积物取代。在所采用的条件下，似乎沉积物可以直接在上皮下位点形成，但复合物也在内皮下形成，解离成游离分子或小复合物，然后穿过致密层迁移并重新形成。
