Mellbye O J, Mollnes T E, Steen L S
Institute of Immunology and Rheumatology, Rikshospitalet, Oslo, Norway.
Clin Immunol Immunopathol. 1994 Jan;70(1):32-9. doi: 10.1006/clin.1994.1007.
To study the IgG subclass distribution and complement activation ability of ANCA, 24 sera containing C-ANCA (cytoplasmatic) and 7 sera containing P-ANCA (perinuclear), as determined by a routine immunofluorescence test, were examined. The subclass distribution was tested by the use of immunofluorescence and ELISA technique and monoclonal antibodies to IgG subclasses. The complement activating activity was studied by the use of immunofluorescence technique and antibodies to C3c and the terminal complement complex (TCC, C5b-9), directed against a neoepitope on C9. For C-ANCA, IgG1 and IgG4 were the dominating subclasses. The subclass distribution differed from that of other autoantibodies tested and that of the total IgG subclass concentrations. For P-ANCA, the results were inconclusive, but the lack of IgG3 was striking. All of the C-ANCA-containing sera caused deposition of C3c, and 50% of the sera gave formation of TCC when reacting with ethanol-fixed granulocytes. P-ANCA-containing sera caused some C3c deposition, but not TCC formation. The unusual IgG subclass distribution for C-ANCA is possibly due to repeated antigenic stimulations and/or to T cell factors influencing the antibody isotype switching. Despite the high IgG4 activity, sera containing C-ANCA are often able to activate complement and are therefore potentially harmful.
为研究抗中性粒细胞胞浆抗体（ANCA）的IgG亚类分布及补体激活能力，我们检测了24份经常规免疫荧光试验确定含有胞浆型抗中性粒细胞胞浆抗体（C-ANCA）的血清以及7份含有核周型抗中性粒细胞胞浆抗体（P-ANCA）的血清。采用免疫荧光和酶联免疫吸附测定（ELISA）技术以及针对IgG亚类的单克隆抗体检测亚类分布。利用免疫荧光技术以及针对C3c和末端补体复合物（TCC，C5b-9）的抗体（该抗体针对C9上的一个新表位）研究补体激活活性。对于C-ANCA，IgG1和IgG4是主要亚类。其亚类分布不同于所检测的其他自身抗体以及总IgG亚类浓度的分布。对于P-ANCA，结果尚无定论，但IgG3的缺失较为显著。所有含C-ANCA的血清与乙醇固定的粒细胞反应时均导致C-3c沉积，50%的血清出现TCC形成。含P-ANCA的血清导致一些C-3c沉积，但未形成TCC。C-ANCA异常的IgG亚类分布可能是由于反复的抗原刺激和/或影响抗体同种型转换的T细胞因子所致。尽管IgG4活性较高，但含C-ANCA的血清通常能够激活补体，因此具有潜在危害性。
