[Monoclonal antibodies against human type IV collagen: preparation and its application in IgA nephropathy].

In the present experiment, BALB/C mice were immunized with type IV collagen from human placenta, afterwards the mouse spleen cells were fused with mouse myeloma line P3 U1. As a result 4 hybridoma cell lines secreting monoclonal antibody against type IV collagen were developed successfully. McAb produced was verified to be isotype of IgG1 and unique as their specificity and purity are concerned. On Western blotting it bound to 120 KD, 95 KD and 60 KD of alpha 1 chain fragments of collagen IV. IF studies of renal biopsy specimen from 38 IgA nephropathy patient were made using this McAb to testify its characterization. Interestingly, it was found that its deposition within glomeruli corresponded to the distribution of collagen IV in general, but varied a great deal in different cases, depending on the presence, severity and extent of mesangial proliferation, sclerosis, crescent formation and tubulo-interstitial lesion. This fact might reflect that collagen IV contents of renal glomeruli in IgA nephropathy patients have developed certain changes either qualitatively or quantitatively, and it might serve as a marker to predict the severity and prognosis of this disease.