Bolton W K, Luo A M, Fox P L, May W J, Sturgill B C
University of Virginia School of Medicine, Department of Medicine, Charlottesville, USA.
Kidney Int. 1995 Feb;47(2):404-10. doi: 10.1038/ki.1995.53.
The Goodpasture's epitope has been mapped to the alpha 3 non-collagenous chain (NC1) of type (IV) collagen [alpha 3col(IV)]. We have developed a model of experimental autoimmune glomerulonephritis (EAG) in rats immunized once with collagenase solubilized GBM (csGBM). Engelbreth-Holm-Swarm (EHS) tumor contains abundant col(IV) with little or no alpha 3col(IV). To test the hypothesis that antigens related to Goodpasture epitope are required to produce EAG in our model, we immunized rats once with 40 micrograms csEHS. Positive controls immunized with csGBM developed typical EAG with GBM bound antibody, proteinuria, and glomerulonephritis. EHS rats developed circulating and bound antibody to mesangium and tubular basement membrane with minimal GBM deposits, but did not develop proteinuria or glomerulonephritis. Although circulating antibody in EHS rats bound to csGBM by ELISA, there was no binding in ELISA to M2 antigen containing the Goodpasture epitope while EAG rat's serum did bind. By Western blot with antisera to Goodpasture epitope, EHS antigen was less complex than GBM in the monomer/dimer regions and appeared to lack NC1 corresponding to alpha 3col(IV). Blotting with sera from EHS rats demonstrated reactivity to various components of GBM but not to alpha 3col(IV). EAG sera and renal eluates bound to alpha 3col(IV). EAG rats evidenced cell mediated immunity while EHS rats did not (stimulation index EHS 1.1, EAG rats 8.0).(ABSTRACT TRUNCATED AT 250 WORDS)
Goodpasture抗原表位已被定位到IV型胶原[α3col(IV)]的α3非胶原链(NC1)上。我们用胶原酶溶解的肾小球基底膜(csGBM)单次免疫大鼠，建立了实验性自身免疫性肾小球肾炎(EAG)模型。Engelbreth-Holm-Swarm(EHS)肿瘤含有丰富的IV型胶原，但α3col(IV)很少或没有。为了验证在我们的模型中产生EAG需要与Goodpasture抗原表位相关的抗原这一假设，我们用40微克csEHS单次免疫大鼠。用csGBM免疫的阳性对照出现了典型的EAG，伴有肾小球基底膜结合抗体、蛋白尿和肾小球肾炎。EHS大鼠产生了针对系膜和肾小管基底膜的循环抗体和结合抗体，肾小球基底膜沉积极少，但未出现蛋白尿或肾小球肾炎。虽然EHS大鼠的循环抗体通过ELISA与csGBM结合，但与含有Goodpasture抗原表位的M2抗原在ELISA中无结合，而EAG大鼠的血清则有结合。用针对Goodpasture抗原表位的抗血清进行Western印迹分析，EHS抗原在单体/二聚体区域比肾小球基底膜的复杂性低，似乎缺乏对应于α3col(IV)的NC1。用EHS大鼠的血清进行印迹分析显示对肾小球基底膜的各种成分有反应，但对α3col(IV)无反应。EAG血清和肾洗脱液与α3col(IV)结合。EAG大鼠表现出细胞介导的免疫，而EHS大鼠则没有(刺激指数EHS为1.1，EAG大鼠为8.0)。(摘要截短至250字)
