Hamoudi W H, Baum L L
Department of Microbiology and Immunology, University of Health Sciences, Chicago Medical School, IL 60064.
J Immunol. 1991 Apr 15;146(8):2873-8.
The studies described in this publication were designed to determine which stage of the NK lytic mechanism is inhibited by anti-C-reactive protein (CRP). Although anti-CRP prevents target cell lysis, it does not block E:T cell conjugate formation. In parallel experiments, the number of conjugates observed in the presence of anti-CRP was normal, whereas the number of target cells killed by this same group of effector cells was greatly inhibited. Since an early stage of NK-mediated lysis requires calcium, conjugates can be synchronized by incubating effector and target cells in the absence of calcium. When conjugates were formed in the absence of calcium, and anti-CRP and calcium were then added to cultures at the same time, anti-CRP inhibited maximally. Anti-CRP continued to inhibit somewhat throughout the calcium-dependent stage but did not block lysis when added after the completion of calcium requiring events. Events that are blocked by anti-CRP must be required for the generation of NK cytotoxic factor because anti-CRP blocks the production of this factor. Once generated, however, anti-CRP does not block the activity of NK cytotoxic factor. This evidence indicates that anti-CRP blocks NK-mediated lysis at the calcium dependent stage of lysis. Events that follow this stage in the lytic process are also inhibited.
本出版物中描述的研究旨在确定抗C反应蛋白（CRP）抑制NK细胞溶解机制的哪个阶段。虽然抗CRP可防止靶细胞裂解，但它并不阻止E:T细胞结合物的形成。在平行实验中，在抗CRP存在下观察到的结合物数量正常，而同一组效应细胞杀死的靶细胞数量则受到极大抑制。由于NK介导的裂解早期需要钙，因此可以通过在无钙条件下孵育效应细胞和靶细胞来使结合物同步化。当在无钙条件下形成结合物，然后同时向培养物中加入抗CRP和钙时，抗CRP的抑制作用最大。在整个钙依赖阶段，抗CRP持续有一定程度的抑制作用，但在需要钙的事件完成后加入时并不阻止裂解。被抗CRP阻断的事件必定是NK细胞毒性因子产生所必需的，因为抗CRP会阻断该因子的产生。然而，一旦产生，抗CRP并不阻断NK细胞毒性因子的活性。这一证据表明，抗CRP在裂解的钙依赖阶段阻断NK介导的裂解。裂解过程中此阶段之后的事件也受到抑制。
