Mittal K R, Ingram D G
Am J Vet Res. 1975 Aug;36(08):1183-7.
The bactericidal activity of blood, plasma, and serum from sheep was measured with 3 strains of Escherichia coli. Plasma showed greater bactericidal activity than blood or serum for strains O78:K80(B) and Lilly. The antibody-complement system of normal serum killed the rough strain, Lilly, but neither antibody nor complement alone were bactericidal. Antibody, complement, and an additional heat-stable cofactor were necessary for killing strain O78:K80(B). Strain 3662 was not susceptible to the lethal action of the antibody-complement system. Capsular and flagellar antibodies did not appear to play any part in the bactericidal activity of serum. There was no relationship between the titer of antibodies to the somatic antigen and the bactericidal titer in the immune serums. The antibodies necessary for killing the smooth strain of E coli, O78:K80(B), were absorbed with the rough strain, Lilly, but not by the other smooth strain, 3662. It is suggested that the target antigen of the bactericidal antibody is not the somatic antigen, but a rough antigen internal to the O polysaccharide.
用3株大肠杆菌测定了绵羊血液、血浆和血清的杀菌活性。对于O78:K80(B)菌株和Lilly菌株，血浆显示出比血液或血清更强的杀菌活性。正常血清的抗体-补体系统可杀死粗糙菌株Lilly，但单独的抗体或补体均无杀菌作用。杀死O78:K80(B)菌株需要抗体、补体和一种额外的热稳定辅助因子。3662菌株对抗体-补体系统的致死作用不敏感。荚膜抗体和鞭毛抗体似乎在血清的杀菌活性中不起任何作用。免疫血清中针对菌体抗原的抗体效价与杀菌效价之间没有关系。杀死光滑型大肠杆菌O78:K80(B)菌株所需的抗体可被粗糙菌株Lilly吸收，但不能被另一光滑菌株3662吸收。提示杀菌抗体的靶抗原不是菌体抗原，而是O多糖内部的一种粗糙抗原。
