抗APO-1单抗促进SEB活化的淋巴细胞凋亡及其与胞内游离Ca^(2+)浓度相关性研究

APOPTOSIS INDUCED BY APO 1 McAb IN ACTIVATED LYMPHOCYTES RELATED WITH THE CYTOSOLIC FREE Ca 2+

为探讨抗ＡＰＯ－１单抗处理的金黄色葡萄球菌肠毒素Ｂ（ＳＥＢ）活化的淋巴细胞胞浆中游离Ｃａ２＋浓度的变化，用形态学观察、流式细胞光度术观测了鼠抗人ＡＰＯ－１单克隆抗体对ＳＥＢ活化不同天数的人外周血淋巴细胞凋亡的诱导作用，同时采用Ｆｕｒａ－２／ＡＭ荧光探针检测了ＡＰＯ－１单抗处理的淋巴细胞胞浆内游离Ｃａ２＋浓度。结果表明，抗ＡＰＯ－１单抗对ＳＥＢ活化１ｄ和对照组淋巴细胞无明显的促凋亡作用，但对ＳＥＢ活化５ｄ的淋巴细胞不仅可明显促进其凋亡，而且可使其胞浆游离Ｃａ２＋浓度升高，而Ｚｎ２＋则抑制了抗ＡＰＯ－１单抗的凋亡诱导作用。由此可见，抗ＡＰＯ－１单抗与其特异性抗体结合后可能是通过使胞浆中游离Ｃａ２＋浓度升高，激活了Ｃａ２＋／Ｍｇ２＋依赖的内源性核酸内切酶而导致ＳＥＢ活化的淋巴细胞凋亡。

Morphological observation and flow cytometry were used to detect the apoptotic promoting effect of APO 1 McAb on the lymphocytes activated by SEB for different days, while the cells were loaded with cytoplasmic fluorescent Ca 2+ indicator fura 2/AM. It is indicated that the lymphocytes activated by SEB for 5 days not only have many apoptosis when cultured with APO 1 McAb, but also elevate their cytoplasmic free [Ca 2+ ]. Zn 2+ can inhibit the apoptosis induced by APO 1 McAb. The phenomenon mentioned above dose not occur in lymphocytes activted by SEB for 1 day and in control group. It suggests that the Ca 2+ /Mg 2+ depended nucleic acid endonuclease in lymphocytes treated with SEB is activated when APO 1 receptors on cells interact with its specific antibody and induce activated lymphocytes apoptosis finally.