Blanco D R, Miller J N, Hanff P A
J Immunol. 1984 Nov;133(5):2693-7.
The neutralizing activity present in immune rabbit serum (IRS) against virulent Treponema pallidum was shown to be mediated by IgG and complement. IgG was isolated and purified from both IRS and nonimmune rabbit serum (NRS) by the use of an affinity system in which staphylococcal protein A was conjugated to Sepharose 4B. The purity of the isolated IgG fractions was demonstrated by both immunoelectrophoresis and SDS-polyacrylamide gel electrophoresis. Fractions of IgG were tested for specific neutralizing activity as measured by an in vitro-in vivo neutralization test. Lesions failed to develop at 80% of the sites inoculated with treponemal suspensions containing IgG from IRS in the presence of unheated NRS as a source of complement; delayed atypical lesions were observed at the remaining sites. In contrast, typical lesions developed at all sites inoculated with suspensions containing IgG from IRS in the presence of heated NRS. They were significantly delayed, however, as compared with lesion development at control sites inoculated with suspensions containing IgG from NRS. These results provide the first direct evidence for an IgG complement-mediated treponemicidal mechanism operative in immune serum from rabbits with latent syphilis.
免疫兔血清（IRS）中存在的针对毒力梅毒螺旋体的中和活性被证明是由IgG和补体介导的。通过使用葡萄球菌蛋白A与琼脂糖4B偶联的亲和系统，从IRS和非免疫兔血清（NRS）中分离并纯化IgG。通过免疫电泳和SDS-聚丙烯酰胺凝胶电泳证明了分离的IgG组分的纯度。通过体外-体内中和试验测定IgG组分的特异性中和活性。在存在未加热的NRS作为补体来源的情况下，接种含有来自IRS的IgG的梅毒螺旋体悬液的部位，80%未出现病变；在其余部位观察到延迟的非典型病变。相比之下，在存在加热的NRS的情况下，接种含有来自IRS的IgG的悬液的所有部位均出现典型病变。然而，与接种含有来自NRS的IgG的悬液的对照部位的病变发展相比，它们明显延迟。这些结果为在潜伏梅毒兔的免疫血清中起作用的IgG补体介导的杀梅毒螺旋体机制提供了首个直接证据。
