Fleischer B, Schmidt K H, Gerlach D, Köhler W
First Department of Medicine, University of Mainz, Germany.
Infect Immun. 1992 May;60(5):1767-70. doi: 10.1128/iai.60.5.1767-1770.1992.
The superantigenic properties of M protein type 5 of Streptococcus pyogenes have been implicated as an important pathogenicity factor in streptococcal autoimmune diseases. Here we show that after a single purification step by affinity chromatography on immobilized albumin or fibrinogen, M protein has no mitogenic activity for T cells. We demonstrate that the superantigenicity of M proteins of type 5 and type 1 is due to contamination with the highly potent pyrogenic exotoxins of S. pyogenes in the range of 0.1 to 0.01%. These results raise a general caveat for work with these extremely active T-cell mitogens, because the mitogenicity of other streptococcal or staphylococcal proteins could be due to similar minute contamination with potent superantigens that are undetectable by any biochemical method but extremely effective in stimulating sensitive T cells.
化脓性链球菌5型M蛋白的超抗原特性被认为是链球菌自身免疫性疾病中的一个重要致病因素。在此我们表明，通过固定化白蛋白或纤维蛋白原亲和层析进行单一纯化步骤后，M蛋白对T细胞没有促有丝分裂活性。我们证明5型和1型M蛋白的超抗原性是由于被化脓性链球菌的高效热原性外毒素污染，污染范围在0.1%至0.01%之间。这些结果对使用这些极具活性的T细胞有丝分裂原的研究提出了一个普遍的警示，因为其他链球菌或葡萄球菌蛋白的促有丝分裂活性可能是由于类似的被强效超抗原的微量污染，而这些超抗原用任何生化方法都无法检测到，但在刺激敏感T细胞方面却极其有效。
