Frazer I H, Mackay I R
Clin Exp Immunol. 1984 Aug;57(2):429-37.
The reactivity of sera in liver diseases was investigated by an immunoradiometric assay for antibody to liver membrane antigens (LMAg). Serum reactivity was similar using glutaraldehyde treated hepatocytes from man and several animals, but the reactivity with human hepatocellular carcinoma cell lines was weak and irregular. F(ab)2 fragments from reactive sera were used in competitive inhibition experiments to ascertain whether anti-LMAg from different liver diseases reacted with the same or different antigenic determinants of the liver membrane. Sera from different patients with autoimmune CAH reacted predominantly with the same membrane components, as did sera from hepatitis B virus associated CAH (CAH-B); however sera from acute viral hepatitis A did not and, since such sera were reactive to LMAg in the assay, other membrane antigens are presumably involved. Enzymatic treatment of viable hepatocytes was performed to determine the nature of the reactive antigen(s): proteases or periodate resulted in reduced binding of reactive sera, but neuraminidase did not, suggesting that the LMAg recognized by CAH sera comprises species non-specific membrane glycoproteins. We conclude, on the basis of quantitative data from a immunoradiometric assay, that antibody to LMAg is more probably reactive than pathogenic, and that assessment of the antigenicity of specific membrane components is necessary.
采用免疫放射分析法定量检测抗肝细胞膜抗原（LMAg）抗体，以研究肝脏疾病患者血清的反应性。用戊二醛处理的人及多种动物的肝细胞检测血清反应性，结果相似，但与人类肝癌细胞系的反应性较弱且无规律。用反应性血清的F(ab)2片段进行竞争抑制实验，以确定不同肝脏疾病的抗LMAg是否与肝细胞膜的相同或不同抗原决定簇发生反应。自身免疫性慢性活动性肝炎（CAH）不同患者的血清主要与相同的膜成分发生反应，乙肝病毒相关性CAH（CAH-B）患者的血清也是如此；然而，甲型急性病毒性肝炎患者的血清并非如此，由于此类血清在检测中对LMAg有反应，推测可能涉及其他膜抗原。对活肝细胞进行酶处理以确定反应性抗原的性质：蛋白酶或高碘酸盐处理可降低反应性血清的结合，但神经氨酸酶处理则无此作用，提示CAH血清识别的LMAg包含种属非特异性膜糖蛋白。基于免疫放射分析的定量数据，我们得出结论，抗LMAg抗体更可能具有反应性而非致病性，且有必要评估特定膜成分的抗原性。
