可溶性Jagged 1/Fc嵌合蛋白对小鼠淋巴细胞活化、增殖和周期的影响

目的:研究可溶性Jagged 1/Fc嵌合蛋白在小鼠淋巴细胞活化、增殖和周期中的作用.方法:选择有效剂量为500 μg/L Jagged 1/Fc嵌合蛋白(Jagged 1/Fc),以活体染料/羧基荧光素乙酰乙酸琥珀酰亚胺酯染色,建立在多克隆刺激剂刀豆蛋白A(ConA)或佛波醇酯(PDB)加离子霉素(Ion)刺激下评价淋巴细胞增殖的模型,通过流式细胞术分析Jagged 1/Fc对淋巴细胞增殖的作用;采用碘化丙锭染色检测Jagged 1/Fc对PDB加Ion刺激的淋巴细胞周期变化的影响;利用荧光标记的mAb双染技术观察Jagged 1/Fc对T细胞早期和中期活化标志CD69和CD25表达的影响.结果:Jagged 1/Fc对ConA刺激或非刺激的CD3 细胞CD69和CD25的表达无明显影响,对ConA或PDB加Ion刺激或非刺激的淋巴细胞的增殖指数也无明显影响,导致非刺激的淋巴细胞sub-G0期细胞百分比增高,S期细胞百分比降低,但并不影响PDB加Ion诱导的淋巴细胞各期的变化.结论:这些结果提示500 μg/L Jagged 1/Fc对小鼠淋巴细胞活化和增殖无明显作用,对PDB加Ion刺激的淋巴细胞周期也无明显影响,但能促进未受刺激的淋巴细胞凋亡,使细胞停滞于GO/G1期,阻止其进入S期.

Effect of a soluble Jagged 1/Fc chimera protein on the activation, proliferation and cell cycle of lymphocytes in mice

AIM: To investigate effect of a soluble Jagged 1/Fc chimera protein (Jagged 1/Fc) on activation, proliferation and cell cycles of lymphocytes in BALB/c mice. METHODS: A model to evaluate the lymphocyte proliferation stimulated with a polyclonal activator, concanavalin A (ConA), was established by a carboxy-fluorescein diacetate-succinimidyl ester (CFDA-SE)-labeling technique. Under an effective dose of 500 mug/L of Jagged 1/Fc, the effect of it on the lymphocyte proliferation was analyzed by flow cytometry. A propidium iodide-labeling technique was applied to estimate the influence of Jagged 1/Fc on the lymphocyte cell-cycle stimulated by phorbol 12,13-dibutyrate (PDB) plus Ionomycin (Ion). Expression levels of CD69 and CD25 molecules on surface of CD3(+) lymphocytes activated with ConA in the presence of Jagged 1/Fc were observed by a fluorescein-conjugated monoclonal antibody-labeling technique. RESULTS: Jagged 1/Fc had no effect on the expression levels of CD69 and CD25 of the CD3(+) lymphocytes stimulated with or without ConA, and no effect on the proliferation index of the lymphocytes stimulated by ConA or PDB plus Ion. It led to the increase of sub-G0 phase cell proportion and the decrease of S phase cell proportion of the lymphocytes, but did not influence the changes of the lymphocyte cell-cycle induced by PDB plus Ion. CONCLUSION: The results suggest that Jagged 1/Fc has no obvious effect on the activation and proliferation of lymphocytes in mice, but may promote the apoptosis of them, cause the G0/G1 phase arrest and block the S phase entry.