Brooks C G, Flannery G R, Webb P J, Baldwin R W
Immunology. 1980 Nov;41(3):673-80.
Cell fractionation techniques were used to identify the cells in rat spleen responsible for natural killing of a syngeneic sarcoma cell in short-term (6 h and 18 h) and long-term (72 h) cytotoxicity assays. Cytotoxicity was quantified precisely using a method previously derived from consideration of natural cytotoxicity as an enzyme-substrate reaction, and by analysing results in terms of lytic units. Killing in all three assays displayed 'single-hit' kinetics implying that a single effector cell was sufficient to lyse a single target cell. The fractionation studies, using glass adherence, carbonyl iron, nylon wool, EA and EAC monolayers and congenitally athymic rats, revealed two populations of cytotoxic cells. In the 6 h assay most of the activity was due to cells with similar characteristics to the NK cells previously defined using leukaemic targets, but in the 18 h and 72 h assays macrophages played an important rôle. The activity exerted by the macrophages was cell lysis and not cytostasis. No evidence that the macrophages acted by releasing factors which stimulated NK cells could be found.
在短期（6小时和18小时）和长期（72小时）细胞毒性试验中，采用细胞分级分离技术来鉴定大鼠脾脏中对同基因肉瘤细胞具有自然杀伤作用的细胞。使用先前从将自然细胞毒性视为酶 - 底物反应推导而来的方法，并通过分析溶解单位的结果来精确量化细胞毒性。在所有这三种试验中，杀伤均呈现“单次打击”动力学，这意味着单个效应细胞足以裂解单个靶细胞。使用玻璃黏附、羰基铁、尼龙毛、EA和EAC单层以及先天性无胸腺大鼠进行的分级分离研究，揭示了两类细胞毒性细胞群体。在6小时试验中，大部分活性归因于具有与先前使用白血病靶标定义的自然杀伤细胞相似特征的细胞，但在18小时和72小时试验中，巨噬细胞发挥了重要作用。巨噬细胞发挥的活性是细胞裂解而非细胞生长抑制。未发现巨噬细胞通过释放刺激自然杀伤细胞的因子来发挥作用的证据。
