明胶酶A、B在脐血CD34+细胞及部分白血病细胞系中的表达

目的　研究骨髓及脐血CD34+ 细胞及白血病细胞系的明胶酶 ,即基质金属蛋白酶 9(MMP 9,明胶酶B)和基质金属蛋白酶 2 (MMP 2 ,明胶酶A)的产生 ,探讨它们在CD34+ 细胞迁移、归巢中的意义及在白血病发病中的作用。方法　通过MiniMACS磁珠分离技术分离脐血及骨髓的CD34+细胞 ,通过酶谱分析法测定脐血、骨髓CD34 + 细胞及白血病细胞系的无血清条件培养液中明胶酶的表达。结果　在脐血CD34+ 细胞的条件培养液中可测出相对分子质量为 92× 10 3的亮带 ,骨髓CD34+ 细胞的条件培养液中未测到亮带。部分白血病细胞系U937、KG 1a、HL 6 0可产生相对分子质量为 92×10 3和 72× 10 3的亮带 ,J6 1、J6 2细胞系可产生相对分子质量为 92× 10 3的亮带 ,而HEL、Namalva、CEM、K5 6 2、LCL H不产生亮带。结论　脐血CD34+ 细胞可产生MMP 9,而骨髓CD34+ 细胞不产生 ,脐血CD34+ 细胞具有较强的穿透基底膜的迁移能力并与MMP 9相关。在白血病细胞系中 ,部分髓系白血病细胞系产生MMP 9和MMP 2 ,而非髓系白血病细胞系不产生。

Expression of gelatinase A and B in cord blood CD34+ cells and leukemic cell lines

OBJECTIVE: To study the expression of gelatinases, including matrix metalloproteinase-9 (MMP-9, gelatinase B) and matrix metalloproteinase-2 (MMP-2, gelatinase A), in CD(34)(+) cells and leukemic cell lines, and explore the significance of gelatinase in migrating and homing capacity of CD(34)(+) cells, as well as the role of gelatinase in leukemia pathogenesis. METHODS: CD(34)(+) cells were isolated from umbilical cord blood and normal bone marrow by Mini MACS system. By zymogram analysis, MMP-2 and MMP-9 were detected in the serum free condition medium of CD(34)(+) cells and cell lines. RESULTS: One brilliant band with molecular weight of 92 x 10(3) was detected in condition medium of cord blood CD(34)(+) cells. No band was detected in condition medium of bone marrow CD(34)(+) cells. Brilliant bands with molecular weight of 92 x 10(3) and 72 x 10(3) were detected in the condition medium of U937, KG-1a and HL-60 cell lines, but not in that of HEL, Namalva, CEM, K562 and LCL-H cell lines. In the condition media of J6-1 and J6-2 cells only the 92 x 10(3) band was detected. CONCLUSIONS: Cord blood CD(34)(+) cells produced MMP-9, but bone marrow CD(34)(+) cells did not, partly explains the fact that cord blood CD(34)(+) cells possessed higher migrating capacity in comparison with bone marrow CD(34)(+) cells. The expression of MMP-9 and MMP-2 in leukemic cell lines varied.