Voermans C, Rood P M, Hordijk P L, Gerritsen W R, van der Schoot C E
Division of Medical Oncology, Netherlands Cancer Institute, Amsterdam, The Netherlands.
Stem Cells. 2000;18(6):435-43. doi: 10.1634/stemcells.18-6-435.
In the process of homing, CD34(+) hematopoietic progenitor cells migrate across the bone marrow endothelium in response to stromal cell-derived factor (SDF)-1. To develop more efficient stem cell transplantation procedures, it is important to define the adhesion molecules involved in the homing process. Here, we identified the adhesion molecules that control the migration of primary human CD34(+) cells across human bone marrow endothelial cells. Migration of CD34(+) cells is enhanced across interleukin 1beta prestimulated bone marrow endothelium, suggesting an important role for the endothelium in adhesion and formation of the chemotactic gradient. Under these conditions, 30-100 ng/ml SDF-1 induced a rapid and efficient migration of CD34(+) cells (+/- 46% migration in 4 h). In contrast, 600-1,000 ng/ml SDF-1 were required for optimal migration across fibronectin-coated filters. Subsequent studies revealed that transendothelial migration of CD34(+) cells is mediated by beta1- and beta2-integrins and PECAM-1 (CD31) but not by CD34 or E-selectin. Whereas these antibodies individually blocked migration for 25%-35%, migration was reduced by 68% when the antibodies were combined. Thus, these adhesion molecules play specific and independent roles in the transmigration process. Finally, O-glycosylated proteins appeared to play a role, since SDF-1-induced migration of CD34(+) cells (treated with a glycoprotease from Pasteurella haemolytica) across endothelial cells was clearly inhibited. In conclusion, we show that efficient SDF-1-induced migration of primary human CD34(+) cells across bone marrow endothelium is mediated by beta1-integrins, beta2-integrins, CD31 and O-glycosylated proteins.
在归巢过程中，CD34(+)造血祖细胞会响应基质细胞衍生因子(SDF)-1而穿过骨髓内皮细胞。为了开发更有效的干细胞移植程序，明确归巢过程中涉及的黏附分子很重要。在此，我们鉴定了控制原代人CD34(+)细胞穿过人骨髓内皮细胞迁移的黏附分子。CD34(+)细胞穿过白细胞介素1β预刺激的骨髓内皮细胞的迁移增强，这表明内皮细胞在黏附和趋化梯度形成中起重要作用。在这些条件下，30 - 100 ng/ml的SDF-1可诱导CD34(+)细胞快速且高效地迁移(4小时内迁移率为±46%)。相比之下，穿过纤连蛋白包被滤器的最佳迁移则需要600 - 1000 ng/ml的SDF-1。后续研究表明，CD34(+)细胞的跨内皮迁移是由β1和β2整合素以及血小板内皮细胞黏附分子-1(CD31)介导的，而不是由CD34或E-选择素介导。虽然这些抗体单独作用时可使迁移阻断25% - 35%，但当这些抗体联合使用时，迁移减少了68%。因此，这些黏附分子在跨膜迁移过程中发挥着特定且独立的作用。最后，O-糖基化蛋白似乎也发挥了作用，因为SDF-1诱导的CD34(+)细胞(用溶血巴斯德菌的糖蛋白酶处理)穿过内皮细胞的迁移明显受到抑制。总之，我们表明SDF-1诱导的原代人CD34(+)细胞穿过骨髓内皮细胞的高效迁移是由β1整合素、β2整合素、CD31和O-糖基化蛋白介导的。
