Dalmasso A P, Lelchuk R, Giavedoni E B, De Isola E D
J Immunol. 1975 Jul;115(1):63-8.
We studied the effects of alkali metal cations on the terminal stages of complement lysis of human and sheep HK erythrocytes. Sensitized erythrocytes (EA) were reacted with limited amounts of complement for 1 hr at 37 degrees C in buffer containing 147 mM NaCl (Na buffer), which resulted in 10-40% lysis. The unlysed cells were washed with Na buffer at 0-2 degrees C and incubated for 1 hr at 37 degrees C in buffers containing 147 mM of the various alkali metal cations. Although additional lysis (25 to 65%) occurred with K, Rb, or Cs buffer, only minor degrees developed with Na or Li buffer, only minor degrees developed with Na or Li buffer. Intermediate levels occurred with 100 mM of the divalent alkali cations. Halogen ions and SCN-(147 MM), Ca++ (0.15mM), and Mg++ (0.5 mM) did not alter the effect of the alkali metal cations. Lysis occurring in K+, Rb+ or Cs+ proceeded without lag, was temperature dependent with an optimum of 43 degrees C, and had a pH optimum of 6.5. Lysis in K and Na buffers was unaffected by 10(-3) to 10(-5) M ouabain. Experiments with mixtures of cations indicated that Na+ had a mild inhibitory effect that could be totally overcome by K+, partially by Rb+, and not at all by Cs+. Li+ had a strong inhibitory effect, 6 X 10(-5) M causing 50% inhibition in buffers containing 147 mM K+, Rb+, or Cs+. By using intermediate complexes of EA and purified complement components we demonstrated that K+ enhances the lytic action of C8 on EAC1-7 as well as that of C9 on EAC1-8. It was known that Li+ facilitates lysis when acting on the entire complement reaction. We found that Li+ enhanced the lytic action of C8 on EAC1-7, with a kinetic that differed from that of the K+ effect. In addition, Li+ inhibited the enhancing effect of K+ upon lysis of EAC1-8 by C9. This occurred at concentration of Li+ similar to those which inhibited the additional lysis by K+, Rb+, and Cs+ of cells that were pretreated in Na buffer with the entire complement sequence. We propose that the major effects of alkali metal cations on complement lysis are due to their interaction with C8 and/or membrane constitutes.
我们研究了碱金属阳离子对人及绵羊HK红细胞补体溶解终末阶段的影响。致敏红细胞（EA）在含147 mM氯化钠的缓冲液（Na缓冲液）中，于37℃与限量补体反应1小时，导致10 - 40%的细胞溶解。未溶解的细胞在0 - 2℃用Na缓冲液洗涤，然后在含147 mM各种碱金属阳离子的缓冲液中于37℃孵育1小时。尽管在K、Rb或Cs缓冲液中会发生额外的溶解（25%至65%），但在Na或Li缓冲液中仅有轻微溶解。在100 mM二价碱金属阳离子存在时出现中间水平的溶解。卤素离子和SCN -（147 mM）、Ca++（0.15 mM）和Mg++（0.5 mM）不改变碱金属阳离子的作用。在K+、Rb+或Cs+中发生的溶解无延迟，与温度有关，最适温度为43℃，最适pH为6.5。在K和Na缓冲液中的溶解不受10(-3)至10(-5) M哇巴因的影响。阳离子混合物实验表明，Na+有轻微抑制作用，可被K+完全克服，部分被Rb+克服，Cs+则完全不能克服。Li+有强烈抑制作用，6×10(-5) M在含147 mM K+、Rb+或Cs+的缓冲液中可导致50%的抑制。通过使用EA与纯化补体成分的中间复合物，我们证明K+增强了C8对EAC1 - 7以及C9对EAC1 - 8的溶解作用。已知Li+作用于整个补体反应时促进溶解。我们发现Li+增强了C8对EAC1 - 7的溶解作用，其动力学与K+效应不同。此外，Li+抑制了K+对C9溶解EAC1 - 8的增强作用。这发生在与抑制用整个补体序列在Na缓冲液中预处理的细胞被K+、Rb+和Cs+额外溶解时相似的Li+浓度下。我们提出碱金属阳离子对补体溶解的主要作用是由于它们与C8和/或膜成分的相互作用。
