Sundsmo J S, Kolb W P, Müller-Eberhard H J
J Immunol. 1978 Mar;120(3):850-4.
The neoantigenic determinants (neoAg) which have been identified in the human C5b-9 membranolytic C complex were detected here by the direct fluorescent antibody technique on the surface of 27 +/- 11% of viable peripheral blood leukocytes (PBL). The cells were prepared from defibrinated blood by sedimentation on Ficoll-Hypaque. Specificity of the antisera was established by quantitative inhibition of the fluorescent staining reaction, and of agglutination of EAC1-7, by highly purified C5b-9 complex. No inhibition was observed with fresh normal human serum. The majority of the PBL with surface neoAg was found in the B lymphocyte subpopulation that failed to form rosettes with sheep erythrocytes. NeoAg on B lymphocytes was removed to differing degrees by trypsin, papain, or pepsin treatment, and by maintaining the cells at 4 degree C for 20 hr in serum-free medium. The individual components, C5, C6, C7, C8, and C9, were also detected on the surface of PBL. With differential fluorescent stains, C5 and neoAg as well as C8 and neoAg could be detected on the same cells. The results indicate that viable B lymphocytes prepared from defibrinated blood, have the components of the membrane attack complex of C on their surface. The concomitant occurrence of the neoAg indicates that these proteins are present at least in part in the form of the assembled terminal complex.
在人C5b - 9膜溶解C复合物中已鉴定出的新抗原决定簇（neoAg），通过直接荧光抗体技术在此处检测到，存在于27±11%的存活外周血白细胞（PBL）表面。细胞由去纤维蛋白血通过在Ficoll - Hypaque上沉降制备。抗血清的特异性通过用高度纯化的C5b - 9复合物对荧光染色反应和EAC1 - 7凝集的定量抑制来确定。新鲜正常人血清未观察到抑制作用。大多数表面有neoAg的PBL存在于不能与绵羊红细胞形成花环的B淋巴细胞亚群中。B淋巴细胞上的neoAg通过胰蛋白酶、木瓜蛋白酶或胃蛋白酶处理，以及在无血清培养基中于4℃将细胞维持20小时，会被不同程度地去除。单个成分C5、C6、C7、C8和C9也在PBL表面被检测到。用差异荧光染色法，可以在同一细胞上检测到C5和neoAg以及C8和neoAg。结果表明，从去纤维蛋白血制备的存活B淋巴细胞表面有补体膜攻击复合物的成分。neoAg的同时出现表明这些蛋白质至少部分以组装的末端复合物形式存在。
