Ax W, Kanzy E J, Seiler F R
Immunobiology. 1981;159(4-5):349-65. doi: 10.1016/S0171-2985(81)80092-7.
The enhancement of bacterial blood clearance in mice by native and enzymatically derived fractions of rabbit anti-E. coli hyperimmune serum was tested. Native immune serum, the corresponding IgG, F(ab')2 and Facb fractions strongly augmented the phagocytosis rate of bacteria, whereas Fab/Fc, Fab, Fc fragments, corresponding preparations from normal serum, and E. coli-absorbed preparations showed no marked enhancing capacity. In one experiment opsonization by IgM was demonstrable. Mice that were injected with fatal doses of bacteria could be protected by subsequent treatment with IgG or F(ab')2 preparations of rabbit anti-E. coli serum. Conclusion is drawn that the Fc region of the IgG molecule is not predominantly responsible for opsonized clearance while the intact divalent antigen cross-linking F(ab')2 fragment - presumably by virtue of complement activation via the alternate pathway - could mediate enhanced bacterial clearance.
测试了兔抗大肠杆菌超免疫血清的天然及酶解衍生组分对小鼠体内细菌血清除率的增强作用。天然免疫血清、相应的IgG、F(ab')2和Facb组分强烈提高了细菌的吞噬率，而Fab/Fc、Fab、Fc片段、来自正常血清的相应制剂以及经大肠杆菌吸收的制剂均未显示出明显的增强能力。在一项实验中，可证明IgM的调理作用。注射致命剂量细菌的小鼠可通过随后用兔抗大肠杆菌血清的IgG或F(ab')2制剂进行治疗而得到保护。得出的结论是，IgG分子的Fc区域并非主要负责调理清除，而完整的二价抗原交联F(ab')2片段——可能是通过替代途径激活补体——可介导增强的细菌清除。
