Hugo F, Reichwein J, Arvand M, Krämer S, Bhakdi S
Infect Immun. 1986 Dec;54(3):641-5. doi: 10.1128/iai.54.3.641-645.1986.
Murine monoclonal antibodies were generated against streptolysin O. One out of 10 tested immunoglobulin clones exhibited strong neutralizing activity; in solution, the presence of approximately two to four antibody molecules per toxin monomer effected 50% neutralization of hemolytic toxin activity. An enzyme-linked immunosorbent assay performed with target cell membranes that were treated with streptolysin O in the presence and absence of neutralizing antibodies showed that the antibodies did not block primary binding of the toxin to the cells. When membranes were solubilized in deoxycholate detergent and centrifuged in sucrose density gradients, those lysed with streptolysin O contained detergent-resistant, high-molecular-weight oligomers identical to the pore lesions, whereas those given toxin and neutralizing antibody contained the toxin exclusively in low-molecular-weight, nonoligomerized form. The process of pore formation by streptolysin O must thus involve two distinct steps, i.e., the primary binding of toxin molecules to the membrane followed by oligomerization of bound toxin monomers by lateral aggregation in the lipid bilayer to form the transmembrane pores.
制备了针对链球菌溶血素O的鼠单克隆抗体。在10个测试的免疫球蛋白克隆中，有1个表现出强大的中和活性；在溶液中，每个毒素单体存在约2至4个抗体分子可使溶血毒素活性中和50%。在有和没有中和抗体的情况下，用链球菌溶血素O处理靶细胞膜进行的酶联免疫吸附测定表明，抗体不会阻断毒素与细胞的初始结合。当细胞膜在脱氧胆酸盐洗涤剂中溶解并在蔗糖密度梯度中离心时，用链球菌溶血素O裂解的细胞膜含有与孔道损伤相同的抗洗涤剂、高分子量寡聚体，而那些同时给予毒素和中和抗体的细胞膜中，毒素仅以低分子量、非寡聚化形式存在。因此，链球菌溶血素O形成孔道的过程必须涉及两个不同的步骤，即毒素分子与膜的初始结合，随后结合的毒素单体通过在脂质双层中的侧向聚集寡聚化形成跨膜孔道。
