Michaelsen T E, Wisloff F, Natvig J B
Scand J Immunol. 1975;4(1):71-8. doi: 10.1111/j.1365-3083.1975.tb02601.x.
Rabbit IgG anti-chicken erythrocyte antibodies were compared with the Fab/c or Facb fragments of IgG and with partially reduced and alkylated IgG for the capacity to induce cytotoxicity by normal human lymphocytes. The Fab/c antibody fragment, which lacks one Fab region, was still able to induce cytotoxicity. In contrast, the Facb antibody fragment, which lacks the C-gamma3 domains, was nearly ineffective in activating the effector cells, whereas intact antibody activity was demonstrated by its ability to inhibit the cytotoxicity induced by unsplit IgG. Similarly, partial reduction and alkylation of the IgG antibodies, under conditions affecting the interchain disulphide bonds only, greatly diminished their ability to induce cytotoxicity, although they effectively inhibited the cytotoxicity induced by untreated IgG. On the basis of these results and previous data, we suggest that the reaction of the Fc region of IgG with the effector cell depends on the integrity of the C-gamma2 domain in the native, divalent state or on the interaction between the C-gamma2 and C-gamma3 domains.
将兔抗鸡红细胞IgG抗体与IgG的Fab/c或Facb片段以及部分还原和烷基化的IgG进行比较，以研究它们诱导正常人淋巴细胞产生细胞毒性的能力。缺少一个Fab区的Fab/c抗体片段仍能诱导细胞毒性。相比之下，缺少C-γ3结构域的Facb抗体片段在激活效应细胞方面几乎无效，而完整抗体通过其抑制未裂解IgG诱导的细胞毒性的能力证明具有活性。同样，仅在影响链间二硫键的条件下对IgG抗体进行部分还原和烷基化，尽管它们能有效抑制未处理IgG诱导的细胞毒性，但其诱导细胞毒性的能力却大大降低。基于这些结果和先前的数据，我们认为IgG的Fc区与效应细胞的反应取决于天然二价状态下C-γ2结构域的完整性，或取决于C-γ2和C-γ3结构域之间的相互作用。
