地中海贫血患儿血清群体反应性抗体对脐血CD34~+细胞增殖和凋亡的影响

本研究探讨特异性群体反应性抗体(panel reactive antibody,PRA)对脐血CD34+细胞的影响。取含PRA的β地中海贫血患儿血清,与脐血CD34+细胞、补体联合孵育,观察其对CD34+细胞的影响,并以[3H]TdR掺入法测定细胞DNA合成及流式细胞仪检测细胞凋亡。结果表明,PRA血清组细胞培养上清中乳酸脱氢酶水平高于对照组;PRA血清组脐血CD34+细胞DNA合成能力较对照组下降。流式细胞仪检测显示,各实验组间脐血CD34+细胞凋亡率差异无统计学意义。结论:特异性PRA血清对脐血CD34+细胞的增殖有抑制作用,补体可增强上述作用;特异性PRA血清对脐血CD34+细胞的凋亡无明显影响。

Effect of thalassemia panel reactive antibody on proliferation and apoptosis of cord blood CD34(+) cells

The study was purposed to explore the effect of panel reactive antibody (PRA) serum from patients with β-thalassemia on proliferation and apoptosis of the CD34(+)cells from cord blood and its mechanism. CD34(+) cells of umbilical cord blood were incubated with different sera and complement respectively. After incubation, the samples were centrifuged and the supernatants were collected for lactate dehydrogenase (LDH) detection, and the CD34(+) cells were harvested and measured for the apoptosis by flow cytometry with Annexin V/PI. The intracellular DNA synthesis were also quantified by [(3)H]TdR incorporation using liquid scintillation counter. The results showed that concentration of LDH in PRA positive groups was higher as compared with control group, and the DNA synthesis of CD34(+) cells in PRA positive groups were inhibited. There were no differences in the percentage of cell apoptosis and necrosis among different groups. It is concluded that thalassemic serum PRA impairs the cell membrane, inhibits the DNA synthesis, which can be increased by addition of the complement, but PRA had no significant effect on apoptosis of CD34(+) cells.