Basta M, Fries L F, Frank M M
Laboratory of Clinical Investigation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20982.
Blood. 1991 Aug 1;78(3):700-2.
We have recently found that intravenous immunoglobulin (IVIg) prevents deposition of C3 and C4 fragments onto antibody sensitized erythrocytes. To find out if such an effect results from the blockade of the recognition phase of the classical complement cascade, we investigated the ability of human serum containing high concentrations of IVIg to deposit the recognition subunit of the first complement component (C1q) onto targets. Normal human serum supplemented in vitro with IVIg did not demonstrate reduced C1q binding to targets as determined by radiolabeled antihuman C1q antibody uptake. Similarly, methylamine-treated normal human serum to which IVIg was added was equally effective in terms of C1q binding as the same serum without IVIg. At increasing doses of sensitizing antibody, C1q uptake decreased proportionally; however, at all antibody dilution points C1q uptake was not significantly different in the serum with IVIg in comparison with normal serum. Serum from a patient treated with IVIg did not differ in its capacity to deposit C1q from the same patient's serum before therapy. Our data suggest that IVIg does not interfere with the recognition step of classical complement pathway. This is a US government work. There are no restrictions on its use.
我们最近发现，静脉注射免疫球蛋白（IVIg）可防止C3和C4片段沉积到抗体致敏的红细胞上。为了弄清楚这种效应是否源于经典补体级联反应识别阶段的阻断，我们研究了含有高浓度IVIg的人血清将第一补体成分（C1q）的识别亚单位沉积到靶标的能力。通过放射性标记的抗人C1q抗体摄取测定，体外补充IVIg的正常人血清并未显示出C1q与靶标结合减少。同样，添加了IVIg的甲胺处理的正常人血清在C1q结合方面与未添加IVIg的相同血清同样有效。随着致敏抗体剂量的增加，C1q摄取量成比例下降；然而，在所有抗体稀释点，与正常血清相比，含有IVIg的血清中C1q摄取量并无显著差异。接受IVIg治疗的患者的血清在沉积C1q的能力上与治疗前该患者的血清没有差异。我们的数据表明，IVIg不会干扰经典补体途径的识别步骤。这是美国政府的工作成果。其使用不受限制。
