Department of Haematology, The First Affiliated Hospital of Zhengzhou University, No. 1 Jianshe East Road, Zhengzhou, 450000, China.
Department of Haematology, Oslo University Hospital Rikshospitalet, Nydalen, Box 4950, 0424, Oslo, Norway.
Sci Rep. 2021 Mar 4;11(1):5127. doi: 10.1038/s41598-021-84695-8.
The infiltration of chronic lymphocytic leukemia (CLL) cells into lymphoid organs correlates with disease severity. CXCL12 is a key chemotactic factor for the trafficking of CLL. Tissue factor pathway inhibitor (TFPI) is a serine protease inhibitor and plays a role in CXCL12-mediated hematopoietic stem cell homing. We aim to explore the role of TFPI in CXCL12-mediated migration of CLL cells. In this study, plasma TFPI concentrations were measured by ELISA. CLL cells were isolated from patients and used for trans-endothelial migration (TEM) assays. Quantitative RT-PCR and Western blotting were used to detect the expression of CXCR7, CXCR4 and β-catenin. Immunofluorescence and co-immunoprecipitation was used to detect the binding of TFPI and glypican-3 (GPC3). We found that plasma TFPI levels in CLL patients were higher than in healthy controls, particularly in the patients with advanced disease. TFPI enhanced CXCL12-mediated TEM of CLL cells by increasing the expression of the CXCL12 receptor CXCR7, but not of the CXCL12 receptor CXCR4. The effect of TFPI on TEM was abolished by the CXCR7 inhibitor, CCX771, while the CXCR4 inhibitor AMD3100 strongly increased TEM. TFPI co-localized with GPC3 on the cell surface. An antibody to GPC3, HS20, decreased CXCR7 expression and abolished the effect of TFPI on TEM. TFPI activated β-catenin and the Wnt/β-catenin inhibitor IWP4 repressed the effect of TFPI on CXCR7 expression and TEM. We conclude that TFPI may contribute to organ infiltration in CLL patients.
慢性淋巴细胞白血病 (CLL) 细胞浸润与疾病严重程度相关。趋化因子 CXCL12 是 CLL 细胞迁移的关键趋化因子。组织因子途径抑制剂 (TFPI) 是一种丝氨酸蛋白酶抑制剂，在 CXCL12 介导的造血干细胞归巢中发挥作用。我们旨在探讨 TFPI 在 CXCL12 介导的 CLL 细胞迁移中的作用。本研究通过 ELISA 法测定血浆 TFPI 浓度。从患者中分离 CLL 细胞，用于跨内皮迁移 (TEM) 测定。定量 RT-PCR 和 Western blot 用于检测 CXCR7、CXCR4 和 β-连环蛋白的表达。免疫荧光和共免疫沉淀用于检测 TFPI 和 GPC3 之间的结合。我们发现 CLL 患者的血浆 TFPI 水平高于健康对照者，尤其是疾病晚期患者。TFPI 通过增加 CXCL12 受体 CXCR7 的表达而非 CXCL12 受体 CXCR4 增强 CXCL12 介导的 CLL 细胞 TEM。CXCR7 抑制剂 CCX771 可消除 TFPI 对 TEM 的影响，而 CXCR4 抑制剂 AMD3100 则强烈增加 TEM。TFPI 与细胞表面的 GPC3 共定位。针对 GPC3 的抗体 HS20 降低了 CXCR7 表达并消除了 TFPI 对 TEM 的影响。TFPI 激活了 β-连环蛋白，Wnt/β-连环蛋白抑制剂 IWP4 抑制了 TFPI 对 CXCR7 表达和 TEM 的影响。我们得出结论，TFPI 可能有助于 CLL 患者的器官浸润。
