巨噬细胞和补体介导的抗体对半抗原结合靶细胞的裂解作用：IgG亚类、抗体和半抗原密度的影响

Antibody mediated lysis of hapten-conjugated target cells by macrophages and by complement: the influence of IgG subclass, antibody and hapten density.

作者信息

Miklós K, Tolnay M, Bazin H, Medgyesi G A

机构信息

National Institute of Haematology and Blood Transfusion, Budapest, Hungary.

出版信息

Mol Immunol. 1992 Mar;29(3):379-84. doi: 10.1016/0161-5890(92)90025-s.

DOI:10.1016/0161-5890(92)90025-s

PMID:1557047

Abstract

Lysis of 51Cr-labeled TNP-SRBC sensitised by rat IgG1 or IgG2a type antibodies by homologous, paraffin oil-elicited peritoneal macrophages (ADCC) or by homologous complement was studied. IgG2a was found to be markedly more efficient in mediating both ADCC and complement dependent lysis compared to IgG1. Inhibition of the ADCC pointed to the involvement of separate but partially overlapping interaction sites for the two isotypes. We suggest that FcRII type receptors play a favoured role in both IgG2a and IgG1 mediated ADCC. The threshold amount of bound antibody required for ADCC was lower than that sufficient for complement dependent lysis regardless on the subclass or on hapten density. The extent of lysis (both ways) was found to depend on hapten density using equal amounts of antibody. The results are interpreted as terms of the possible requirements for association of IgG molecules on the target cell surface.

摘要

研究了用大鼠IgG1或IgG2a型抗体致敏的51Cr标记的三硝基苯-绵羊红细胞（TNP-SRBC），经同源的、石蜡油诱导的腹腔巨噬细胞介导的抗体依赖的细胞介导的细胞毒作用（ADCC）或经同源补体作用而发生溶解的情况。结果发现，与IgG1相比，IgG2a在介导ADCC和补体依赖性溶解方面明显更有效。ADCC的抑制表明，这两种同种型的相互作用位点是分开的，但部分重叠。我们认为，FcRII型受体在IgG2a和IgG1介导的ADCC中都发挥着有利作用。ADCC所需的结合抗体阈值量低于补体依赖性溶解所需的量，无论亚类或半抗原密度如何。使用等量抗体时，发现溶解程度（两种方式）取决于半抗原密度。这些结果被解释为IgG分子在靶细胞表面结合的可能要求。