Jepsen H H, Møller Rasmussen J, Teisner B, Schrøder L, Holmskov U, Jarlbaek L, Isager H, Svehag S E
Institute of Medical Microbiology, Odense University, Denmark.
APMIS. 1990 Jul;98(7):637-44. doi: 10.1111/j.1699-0463.1990.tb04981.x.
Erythrocytes (E) from a cross-sectional group of 22 outpatients with systemic lupus erythematosus (SLE) and/or mixed connective tissue disease (MCTD), the majority without active disease (n = 14), were analyzed for CR1 antigen expression and capacity to bind complement opsonized, radiolabelled immune complexes (IC). Furthermore, E-bound C3 fragments and the plasma C3d concentration were determined. E-bound C3b/iC3b fragments were not elevated in patients with SLE, whereas E from 11 out of 22 SLE patients had increased C3d levels which correlated with the plasma C3d concentration (Rs 0.73, p less than 0.001). E-fixed C3d fragments did not affect the binding of Mab or preopsonized IC to E-CR1 and were not correlated with disease activity or medical treatment. Antigen expression of E-CR1 measured by ELISA or agglutination showed positive correlation with the IC binding capacity of E-CR1 (Rs 0.92 and 0.72 respectively, p less than 001). The IC binding capacity of E-CR1 from SLE patients was significantly reduced (p less than 0.005), whereas the antigen expression of CR1 (ELISA) on E from the patients did not differ from that of E from healthy donors (p greater than 0.1). E-CR1 antigen was measured by Mab reacting with an epitope outside the IC-binding site of E-CR1. E-CR1 antigen expression or IC binding showed no correlation either with disease activity or prednisolone treatment. However, 4 og 5 patients with MCTD and 4 of 5 patients receiving Imurel were found to have low E-CR1 expression and capacity to bind IC. Thus, measurement of antigenic E-CR1 in a cross-sectional group of SLE outpatients by use of Mab reacting with an epitope outside the ligand-binding region of CR1 did not reveal a significantly reduced CR1 expression. However, an assay for CR1-mediated IC binding showed a clearly reduced E-CR1 function.
对22例系统性红斑狼疮（SLE）和/或混合性结缔组织病（MCTD）门诊患者的红细胞（E）进行了分析，这些患者来自一个横断面研究组，大多数患者无活动性疾病（n = 14），分析内容包括CR1抗原表达以及结合补体调理的、放射性标记免疫复合物（IC）的能力。此外，还测定了E结合的C3片段和血浆C3d浓度。SLE患者E结合的C3b/iC3b片段未升高，而22例SLE患者中有11例的E的C3d水平升高，且与血浆C3d浓度相关（Rs = 0.73，p < 0.001）。E固定的C3d片段不影响单克隆抗体（Mab）或预调理IC与E-CR1的结合，且与疾病活动度或治疗无关。通过酶联免疫吸附测定（ELISA）或凝集法检测的E-CR1抗原表达与E-CR1的IC结合能力呈正相关（Rs分别为0.92和0.72，p < 0.001）。SLE患者E-CR1的IC结合能力显著降低（p < 0.005），而患者E上CR1的抗原表达（ELISA）与健康供者E上的抗原表达无差异（p > 0.1）。E-CR1抗原通过与E-CR1的IC结合位点外的表位反应的Mab进行测定。E-CR1抗原表达或IC结合与疾病活动度或泼尼松龙治疗均无相关性。然而，发现5例MCTD患者中有4例以及接受硫唑嘌呤治疗的5例患者中有4例E-CR1表达低且IC结合能力低。因此，在一组SLE门诊患者的横断面研究中，使用与CR1配体结合区域外的表位反应的Mab测定抗原性E-CR1，未发现CR1表达显著降低。然而，一项针对CR1介导的IC结合的检测显示E-CR1功能明显降低。
