Thorsteinsson L, Michaelsen T E, Frøland S S
Int Arch Allergy Appl Immunol. 1980;62(1):111-7. doi: 10.1159/000232501.
Intact rabbit IgG antisheep erythrocyte antibodies, and the corresponding F(ab')2 fragments and partially reduced and alkylated IgG were studied for the capacity to induce cytotoxic plaque formation by normal human mononuclear leukocytes in surface monolayers of sheep erythrocytes. The F (ab')2 fragments did not induce plaque formation, whereas partially reduced and alkylated IgG antibodies had a good plaque-inducing capacity compared to untreated IgG anti-SRBC antibodies. The plaque formation was inhibited by human IgG, but not by IgM, IgA, IgD or IgE. Normal and myeloma IgG in aggregated form gave a stronger inhibition than the corresponding proteins. Strong inhibition was observed with IgG1, IgG3, and IgG4, and with IgG2 after aggregation. Both the Fc and pFc' corresponding to the C terminal domain gave a strong inhibition. Thus, the region of the IgG molecule involved in binding to the Fc receptor of the plaque-forming cells appears to be located within the CH3 domain. These observations, therefore, indicate that the plaque-forming cells are of monocytic origin.
对完整的兔抗绵羊红细胞IgG抗体、相应的F(ab')2片段以及部分还原和烷基化的IgG进行了研究，以探讨它们在绵羊红细胞表面单层中诱导正常人单核白细胞形成细胞毒性噬斑的能力。F(ab')2片段不能诱导噬斑形成，而部分还原和烷基化的IgG抗体与未处理的抗绵羊红细胞IgG抗体相比，具有良好的噬斑诱导能力。噬斑形成受到人IgG的抑制，但不受IgM、IgA、IgD或IgE的抑制。聚集形式的正常IgG和骨髓瘤IgG比相应的蛋白质产生更强的抑制作用。观察到IgG1、IgG3和IgG4以及聚集后的IgG2有强烈的抑制作用。与C末端结构域相对应的Fc和pFc'均产生强烈的抑制作用。因此，IgG分子中与噬斑形成细胞的Fc受体结合的区域似乎位于CH3结构域内。因此，这些观察结果表明，噬斑形成细胞起源于单核细胞。
