Monoclonal antibodies demonstrate protection of polymorphonuclear leukocytes against complement attack

摘要: Studies on erythrocytes have shown that the formation of membrane attack complex a cell surface inevitably results in lysis. However, it is known nucleated cells are much more difficult to kill with complement1–3, although molecular basis this resistance has never been established. We very early intracellular event, occurring within seconds membrane, rise cytoplasmic Ca2+ (ref. 4), which can activate responses without death5,6. Here we report use monoclonal antibody terminal complement component C9 (refs 7, 8, 13), quantified by 125I and visualized fluorescein, demonstrate protection mechanism polymorphonuclear leukocytes (PMNs) attacked complement, involving removal vesiculation. Concomitantly, there Ca2+-dependent activation reactive oxygen metabolite production These findings important implications evolutionary pathological significance components pathway.