Point mutations of single amino acids abolish ability of alpha3 NC1 domain to elicit experimental autoimmune glomerulonephritis in rats.
Point mutations of single amino acids abolish ability of alpha3 NC1 domain to elicit experimental autoimmune glomerulonephritis in rats.
复制标题
单个氨基酸的点突变消除了 α3 NC1 结构域在大鼠中引发实验性自身免疫性肾小球肾炎的能力。
DOI：
10.1074/jbc.m211951200
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发表时间：
2003
期刊：
影响因子：
--
通讯作者：
Bolton,WarrenKline
中科院分区：
文献类型：
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作者：
Hellmark,Thomas;Chen,Lanlin;Ohlsson,Sophie;Wieslander,Jörgen;Bolton,WarrenKline
We previously showed concordance between Goodpasture syndrome antibody binding and production of experimental glomerulonephritis using human chimeric proteins. We now examine a more limited amino-terminal region of α3(IV) non-collagenous domain (NC1) and the impact of single amino acid (AA) mutations of this region on glomerulonephritis induction. Rats were immunized with collagenase-solubilized glomerular basement membrane (csGBM), D3, an α1(IV)NC1 chimeric protein with 69 AA of α3(IV)NC1 (binds Goodpasture sera), D4, the D3 construct shortened by 4 AA (non-binding), P9, P10, single AA mutants (non-binding), and S2, α1(IV)NC1 with 9 AA of α3(IV)NC1 (binding). All rats immunized with csGBM and S2 and 50% of D3 rats developed glomerulonephritis. csGBM rats had intense GBM-bound IgG deposits, but S2 and D3 rats had minimal deposits. None of the D4, P9, or P10 rats developed glomerulonephritis. Lymphocytes from nephritic rats proliferated with csGBM, S2, and D3, but not with D4, P9, or P10. Discrete segments of α3(IV)NC1 within the α1(IV)NC1 backbone can induce glomerulonephritis. Single AA mutations within that epitope render the antigen unresponsive to Goodpasture sera and incapable of inducing glomerulonephritis. These studies support the concordance of glomerulonephritis inductivity and Goodpasture serum binding. Further, they define a critical limited AA sequence within α3(IV)NC1 of nine or fewer AA, which confers nephritogenicity to the nonnephritogenic α1(IV)NC1 withoutin vivoantibody binding. This region may be a T-cell epitope responsible for induction of glomerulonephritis in this model in rats and Goodpasture syndrome in man.
