Axcrona K, Björck L, Leanderson T
Immunology Unit, University of Lund, Sweden.
Scand J Immunol. 1995 Sep;42(3):359-67. doi: 10.1111/j.1365-3083.1995.tb03668.x.
A group of bacterial Ig-binding surface proteins were studied: protein H and M1 are from Streptococcus pyogenes and interact with IgG, protein L is expressed by Peptostreptococcus magnus and shows affinity for Ig light chains, whereas protein LG is a chimeric construction combining the binding properties of protein L with the IgG-binding activity of protein G from group C and G streptococci. Proteins L and H coupled to Sepharose were mitogenic for human peripheral blood lymphocytes (PBL) and mouse splenic B cells, but not when added in soluble form. Differentiation to Ig secretion was induced by protein H-Sepharose in mouse splenic B cells but not in human PBLs. In FACS analysis FITC-labelled protein H stained virtually all CD19+ cells in human peripheral blood as well as a majority of the CD3+ population. Protein L bound the majority of the CD19+ population, but also a fraction of the CD19-/CD3 population. Protein M1 was not mitogenic but stained the entire CD19+ population and 70% of the CD3+ population. Identical staining patterns were observed with mouse splenocytes using B220 and T-cells receptor as lineage markers. The chimeric protein LG was a potent mitogen for mouse splenic B cells when added either coupled to Sepharose or in soluble form. In addition, protein LG induced differentiation to Ig secretion of the responding mouse splenic B cells. In FACS analysis, protein LG stained the entire CD19+ and the majority of the CD19-/CD3 lymphocyte population as well as all B220+ mouse splenocytes and a fraction of the splenic T cells. These data indicate that the bacterial proteins studied interact with surface structures of several leucocyte populations and can hence interfere with the immune system at multiple levels.
对一组细菌Ig结合表面蛋白进行了研究：蛋白H和M1来自化脓性链球菌，可与IgG相互作用；蛋白L由巨大消化链球菌表达，对Ig轻链具有亲和力；而蛋白LG是一种嵌合结构，结合了蛋白L的结合特性与C组和G组链球菌中蛋白G的IgG结合活性。与琼脂糖偶联的蛋白L和H对人外周血淋巴细胞（PBL）和小鼠脾B细胞有促有丝分裂作用，但以可溶性形式添加时则无此作用。蛋白H-琼脂糖可诱导小鼠脾B细胞分化为Ig分泌细胞，但对人PBL则无此作用。在流式细胞术分析中，异硫氰酸荧光素标记的蛋白H几乎可染色人外周血中的所有CD19+细胞以及大部分CD3+细胞群体。蛋白L结合了大部分CD19+细胞群体，但也结合了一部分CD19-/CD3细胞群体。蛋白M1无促有丝分裂作用，但可染色整个CD19+细胞群体和70%的CD3+细胞群体。使用B220和T细胞受体作为谱系标记，在小鼠脾细胞中观察到了相同的染色模式。嵌合蛋白LG无论是与琼脂糖偶联添加还是以可溶性形式添加，对小鼠脾B细胞都是一种有效的促有丝分裂原。此外，蛋白LG可诱导反应性小鼠脾B细胞分化为Ig分泌细胞。在流式细胞术分析中，蛋白LG可染色整个CD19+细胞群体、大部分CD19-/CD3淋巴细胞群体以及所有B220+小鼠脾细胞和一部分脾T细胞。这些数据表明，所研究的细菌蛋白与几种白细胞群体的表面结构相互作用，因此可在多个水平上干扰免疫系统。
