单克隆抗体HIM82对人中性粒细胞钙离子和蛋白激酶及酪氨酸激酶？…

目的 研究单克隆抗体（单抗）ＨＩＭ８２对中性粒细胞（Ｎｐ）呼吸爆发产生的活性氧物质（ＲＯＳ）的调控作用，并探索ＨＩＭ８２对该调控作用相关联的信息传递途径的影响。方法 比较对照组与实验组（单抗结合组）在趋化物激活后，ＲＯＳ水平，对Ｇ蛋白抑制的影响，胞内水平，蛋白激酶Ｃ（ＰＫＣ），酪氨酸激酶（ＰＴＫ）活性的差异而判别该单抗对ＲＯＳ及有关信息途径的影响。结果 ＨＩＭ８２与Ｎｐ结合的阳性率达９５％以上（对

Down-regulation effect of McAb HIM82 on Ca2+, protein kinase C, protein tyrosine kinase signal pathway of neutrophils]

OBJECTIVES: To study the control effects of HIM82 and HIM70 on reactive oxygen species (ROS) released from respiratory burst of neutrophils (Np), and the action of HIM82 on relevant signal transduction pathway. METHODS: The experimental group (combining with McAb) was compared with the control group with regard to the ROS level, activity of G protein, intracellular Ca2+] level, the activities of PKC and PTK in activated Np to interpret the mechanism by which the McAb down-regulated the respiratory burst. RESULTS: The positive rate of Np combined with HIM82 was shown over 95% using indirect immunofluorescence assay (control group was 0). The generation of superoxide anion and hydrogen peroxide from PMA-treated Np were decreased by 55% (P < 0.01) and 32% (P < 0.01) with 30 micrograms/ml HIM82. The amount of H2O2 produced in FMLP or SP-stimulated Np were decreased by 16% (P < 0.01) and 37% (P < 0.01) respectively. A similar effect of HIM70 on Np was observed. Furthermore, the inhibition of H2O2 in FMLP-activated Np affected by PT, a specific inhibitor for G-protein, and in HIM82 was 42% and 60% separately, and that with both PT and HIM82 was 85%. It was suggested that HIM82 could enhance the inhibition effect of PT on G-protein. The intracellular Ca2+] level of Np stimulated with FMLP was decreased by 85%, and that of Np activated with PMA by 100% nearly in the present of HIM82. The activities of PKC and PTK in PMA-stimulated Np were decreased by 23% (P < 0.05) and 35% (P < 0.05) separately when treated with HIM82. CONCLUSION: The McAb HIM82 could down-regulate the ROS produced from activated Np. The mechanism of decreasing ROS may be involved in down-regulating Ca(2+)-PKC and PTK signal transduction pathway activities that are upstream control systems for NADPH oxidase activation.