Daha M R, Hazevoet H M, van Es L A
Clin Exp Immunol. 1984 Jun;56(3):614-20.
F-42, an autoantibody found in the sera of some patients with systemic lupus erythematosus, was isolated from sera of seven different patients. By binding of the autoantibodies to cell bound C42, the autoantibodies were purified to homogeneity and radiolabelled with 125I. Purified preparations of 125I-F-42 were bound for at least 96% by 10(9) erythrocytes bearing C4bhuC2hu. Analysis of all 125I-F-42 preparations by SDS-PAGE demonstrated apparent mol. wts of approximately 150,000. After reduction in the presence of 8 M urea each 125I-F-42 preparation yielded heavy and light chains. The heavy chains in some instances were slightly heavier than the heavy chain of normal human IgG. The reaction of 125I-F-42 from the seven patients was positive with Sepharose bound antisera to IgG, kappa, lambda, gamma 1, gamma 2, gamma 3 and in one case to gamma 4. These studies indicate that F-42 is an autoantibody directed against antigens expressed by the classical C3 convertase, C42.
F-42是在一些系统性红斑狼疮患者血清中发现的一种自身抗体，它是从7名不同患者的血清中分离出来的。通过将自身抗体与细胞结合的C42相结合，这些自身抗体被纯化至同质，并使用125I进行放射性标记。125I-F-42的纯化制剂至少96%与带有C4bhuC2hu的10(9)个红细胞结合。通过SDS-PAGE对所有125I-F-42制剂进行分析，显示其表观分子量约为150,000。在8 M尿素存在下进行还原后，每种125I-F-42制剂都产生了重链和轻链。在某些情况下，重链比正常人IgG的重链略重。来自这7名患者的125I-F-42与琼脂糖结合的抗IgG、κ、λ、γ1、γ2、γ3血清反应呈阳性，在1例中与γ4血清反应呈阳性。这些研究表明，F-42是一种针对经典C3转化酶C42所表达抗原的自身抗体。
