T淋巴细胞对人骨髓造血细胞体外扩增的负调节作用

Negative Regulatory Effect of T-Lymphocytes on the Expansion of Human Bone Marrow Hematopoietic Cells In Vitro

采用抗CD3或抗CD8单克隆抗体的补体细胞毒方法体外清除人骨髓MNC(单个核细胞 )中的T淋巴细胞和用流式细胞技术 (FACS)分析细胞表面标志 ,观察人骨髓T淋巴细胞对造血细胞增殖的负调节效应。将MNC加入含多种造血生长因子的培养基进行液态扩增并检测其CD34+细胞绝对数、粒 巨噬集落 (CFU GM )和多向祖细胞集落 (CFU GEMM )形成能力。结果表明 ,抗CD3,抗CD8或抗CD3+抗CD8单抗清除T淋巴细胞的骨髓MNC ,其细胞总数经造血生长因子刺激培养 2 0天分别扩增了 75 .8,79.6和 77.4倍 ,明显高于对照组 (6 7.0倍 )。体外培养 6天时CD8清除组CD34+ 细胞的扩增最高可提高 17.82 %。上述 3个清除组的CFU GM产率分别为 173.6 7± 18.90 ,16 5 .33± 2 6 .5 8和 170 .33± 2 1.5 0 ,对照组 79.6 7± 8.33。这 3个清除组与对照组比较差异显著 (P <0 .0 5 )。上述 3个清除组的CFU GEMM产率分别为 4 31.33± 34.5 6 ,370 .33± 4 2 .10和 386 .6 7± 10 .0 2 ,对照组为 177.6 7± 2 6 .86。这 3个清除组与对照组比较P值分别为 <0 .0 0 2 ,<0 .0 5和 <0 .0 0 5。此研究结果提示骨髓中T淋巴细胞可以抑制造血细胞的体外扩增、CFU GM和CFU GEMM产率 ,其作用机制有待进一步探讨。

In this research, the regulatory effects of T-lymphocytes on the expansion of hematopoietic cells in human bone marrow were studied. Anti-CD3 McAb and anti-CD8 McAb were used to eliminate the T-lymphocytes in bone marrow MNCs. Cell surface antigens were analysed by flow cytometry. Hematopoietic cells expanded with hematopoietic growth factors(HGFs) in a liquid culture system and the number of CD34 + cell, CFU-GM and CFU-GEMM were determined. After cultured with HGFs for 20 days the total number of cells expanded by 75.8, 79.6, 77.4 and 67.0 folds respectively in three experimental groups (anti-CD3 McAb, anti-CD8 McAb and anti-CD3+anti-CD8 McAb) and control group (MNC of bone marrow). The number of CFU-GM in the four groups were 173.67±18.90, 165.33±26.58, 170.33±21.50 and 79.67±8.33 respectively. The number of CFU-GEMM in the four groups were 431.33±34.56, 370.33±42.10, 386.67±10.02 and 177.67±26.86 respectively. There were significant differences in the number of CFU-GM and CFU-GEMM between experimental groups and control group. The results showed that the T-lymphocytes in bone marrow could inhibit the expansion of hematopoietic cells in vitro and the formation of CFU-GM and CFU-GEMM. The regulatory mechanism was to be explored.