Darzynkiewicz Z, Traganos F, Andreeff M, Sharpless T, Melamed M R
J Histochem Cytochem. 1979 Jan;27(1):478-85. doi: 10.1177/27.1.86572.
The properties of DNA in situ as reflected by its staining with acridine orange are different in quiescent nonstimulated lymphocytes as compared with interphase lymphocytes that have entered the cell cycle after stimulation by mitogens. The difference is seen after cell treatment with buffers at pH 1.5 (1.3-1.9 range) followed by staining with acridine orange at pH 2.6 (2.3-2.9). Under these conditions the red metachromatic fluorescence of the acridine orange-DNA complex is higher in quiescent cells than in the cycling lymphocytes while the orthochromatic green fluorescence is higher in the cycling, interphase cells. The results suggest that DNA in condensed chromatin of quiescent lymphocytes (as in metaphase chromosomes) is more sensitive to acid-denaturation than DNA in dispersed chromatin of the cycling interphase cells. The phenomenon is used for flow cytometric differentiation between G0 and G1 cells and between G2 and M cells. In contrast to normal lymphocytes the method applied to neoplastic cells indicates the presence of cell subpopulations with condensed chromatin but with DNA content characteristic not only of G1 but also of S and G2 cells. The possibility that these cells represent quiescent (resting) subpopulations, arrested in G1, S and/or G2, is discussed.
与经有丝分裂原刺激后进入细胞周期的间期淋巴细胞相比，用吖啶橙染色所反映的静息未刺激淋巴细胞中DNA的原位特性有所不同。在用pH 1.5（1.3 - 1.9范围）的缓冲液处理细胞后，再用pH 2.6（2.3 - 2.9）的吖啶橙染色，这种差异就会显现出来。在这些条件下，吖啶橙 - DNA复合物的红色异染荧光在静息细胞中比在循环淋巴细胞中更高，而正色绿色荧光在循环的间期细胞中更高。结果表明，静息淋巴细胞浓缩染色质中的DNA（如同中期染色体中的DNA）比循环间期细胞分散染色质中的DNA对酸变性更敏感。这种现象被用于流式细胞术区分G0和G1细胞以及G2和M细胞。与正常淋巴细胞不同，应用于肿瘤细胞的该方法表明存在具有浓缩染色质但DNA含量不仅具有G1特征还具有S和G2细胞特征的细胞亚群。文中讨论了这些细胞代表停滞在G1、S和/或G2期的静息亚群的可能性。
