Stafford H A, Anderson C J, Reichlin M
Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City 73104, USA.
J Immunol. 1995 Sep 1;155(5):2754-61.
Autoantibodies to the ribosomal P proteins (anti-P) are found almost exclusively in a subset of patients with systemic lupus erythematosus. To determine if anti-P autoantibodies are present in healthy individuals but in a masked state, sera from healthy adults were applied to affinity columns coated with ribosomes, and the affinity-purified fractions were analyzed for anti-P Abs by ELISA and immunoblot. Anti-P Abs were detectable in serum only after affinity chromatography, were predominantly of the IgG isotype, stained HEp-2 cells in the characteristic anti-P pattern, and demonstrated specificity for all three ribosomal P phosphoproteins. Using batch affinity chromatography, we identified anti-P autoantibodies in the affinity-purified serum fractions of 54 of 55 healthy individuals. Anti-P Abs from healthy adults generally bound less ribosomal P Ag per mg/ml IgG than anti-P from patients. Inhibition studies revealed that autologous serum contained an IgG inhibitor of anti-P Ab. We conclude that masked anti-P autoantibodies are present in the healthy population and hypothesize that detection of these autoantibodies in systemic lupus erythematosus represents disruption of these regulatory networks.
核糖体P蛋白自身抗体（抗P抗体）几乎仅在系统性红斑狼疮患者的一个亚组中发现。为了确定抗P自身抗体是否存在于健康个体中但处于隐匿状态，将健康成年人的血清应用于包被有核糖体的亲和柱，并通过酶联免疫吸附测定（ELISA）和免疫印迹法分析亲和纯化组分中的抗P抗体。仅在亲和层析后血清中可检测到抗P抗体，其主要为IgG同种型，以特征性抗P模式染色人喉表皮样癌细胞（HEp-2细胞），并对所有三种核糖体P磷蛋白表现出特异性。使用批量亲和层析，我们在55名健康个体中的54名的亲和纯化血清组分中鉴定出抗P自身抗体。与患者的抗P抗体相比，健康成年人的抗P抗体通常每毫克/毫升IgG结合的核糖体P抗原较少。抑制研究表明，自体血清含有抗P抗体的IgG抑制剂。我们得出结论，隐匿性抗P自身抗体存在于健康人群中，并推测在系统性红斑狼疮中检测到这些自身抗体代表这些调节网络的破坏。
