Spranzi E, Djeu J Y, Hoffman S L, Epling-Burnette P K, Blanchard D K
Department of Medical Microbiology & Immunology, University of South Florida College of Medicine, H. Lee Moffitt Cancer Center and Research Institute, Tampa 33612.
Blood. 1993 Sep 1;82(5):1578-85.
The present study shows that extracellular adenosine triphosphate (ATP) has the capacity to mediate dose-dependent lysis of the monocytic leukemia cell line THP-1. The lysis, assessed by 51Cr release, was found to be selective for ATP, because adenosine diphosphate (ADP) or other nucleotides were less effective in their ability to lyse the cells. The amount of 51Cr released was particularly enhanced by the stimulation of the cells with 1,000 U/mL of interferon gamma (IFN-gamma) for 3 days, and the sensitivity was time and dose dependent. Analysis of the mechanism of lysis indicated that the fully ionized form, ATP4-, mediated the lysis, because the addition of cation chelators or the absence of the divalent cations, Ca2+ and Mg2+, in the culture medium of a 6-hour 51Cr release assay increased the percent specific lysis. Therefore, the ATP receptors on THP-1 cells were classified as P2Z purinoceptors. Moreover, it is shown here that the Ca2+/calmodulin complex plays a role in the regulation of the lysis by extracellular ATP of THP-1 cells, because antagonists of this complex, such as trifluoperazine or KN-62, were found to inhibit the ATP-mediated cell lysis.
本研究表明，细胞外三磷酸腺苷（ATP）具有介导单核细胞白血病细胞系THP-1剂量依赖性裂解的能力。通过51Cr释放评估发现，这种裂解对ATP具有选择性，因为二磷酸腺苷（ADP）或其他核苷酸在裂解细胞的能力方面效果较差。用1000 U/mL的γ干扰素（IFN-γ）刺激细胞3天，51Cr释放量显著增加，且敏感性具有时间和剂量依赖性。对裂解机制的分析表明，完全电离形式的ATP4-介导了裂解，因为在6小时的51Cr释放试验的培养基中添加阳离子螯合剂或不存在二价阳离子Ca2+和Mg2+会增加特异性裂解百分比。因此，THP-1细胞上的ATP受体被归类为P2Z嘌呤受体。此外，本文还表明Ca2+/钙调蛋白复合物在调节THP-1细胞外ATP介导的裂解中起作用，因为发现该复合物的拮抗剂，如三氟拉嗪或KN-62，可抑制ATP介导的细胞裂解。
