梯度氧浓度下多形核白细胞的趋化特性与机制  

Mechanism of polymorphonuclear leukocytes chemotaxis in oxygen gradient

作　　者：宓保梅 黄瑊[2] 李晓栩[2] 官立彬[2] 崔宇[2] 梁潇[1] 杨诚忠 沈宜[1] 

机构地区：[1]重庆医科大学基础医学院病理生理学教研室干细胞与组织工程研究室,400016 [2]第三军医大学高原军事医学系高原生理学与高原生物学教研室高原医学教育部重点实验室全军高原医学重点实验室,重庆400038

出　　处：《免疫学杂志》2015年第4期293-296,301,共5页Immunological Journal

基　　金：国家973计划(2012CB518201);国家自然科学基金(81370150;30973446)

摘　　要：目的探讨梯度氧浓度下大鼠多形核白细胞的趋化特性与机制。方法用ibidi 6通道细胞趋化板观察白细胞在梯度下氧浓度的趋化方向。用48孔趋化小室趋化板观察趋化因子作用于白细胞后在缺氧条件下的趋化能力以及白细胞缺氧培养上清的趋化能力,结合甲酰肽受体拮抗剂,分析缺氧白细胞上清中甲酰肽受体激动剂水平。用免疫印迹检测多形核白细胞不同缺氧时间(0、3、6、12、24 h)或趋化因子作用后葡萄糖转运体1的表达。结果在梯度氧浓度下,白细胞趋化呈现明显的方向性,白细胞向梯度氧浓度的低氧侧迁移。细胞缺氧培养上清诱导的趋化反应显著高于常氧培养上清,用甲酰肽受体特异性拮抗剂可显著削弱这一反应。用甲酰肽受体激动剂预处理或缺氧预处理显著增强白细胞在缺氧条件下对血清的趋化反应,并剂量依赖性地上调白细胞葡萄糖转运体1表达,显著增强在缺氧条件下的葡萄糖摄取率。结论多形核白细胞逆梯度氧浓度趋化,其机制可能与低氧促进靠近低氧侧的细胞释放甲酰肽受体激动剂等趋化因子有关。这些趋化因子在诱导趋化的同时提高白细胞葡萄糖摄取能力,从而提高白细胞无氧代谢能力或省氧能力。Infiltration a nd function execution of inflammatory cells need more oxygen to produce ATP.However, it is unclear how inflammatory cells resolve the contradiction of oxygen supply and need. In this study we aimed to investigate the characteristics and mechanism of polymorphonuclear leukocytes（PMN） chemotaxis in oxygen gradient. The Ibidi six-channel cell chemotaxis assay was used to observe PMN movement in 21%→0% O2gradient; chemoattractant-induced chemotaxis was measured in a 48-well chamber. After hypoxia or f MLP（N-formylmethionyl-leucyl-phenylalanine, an agonist of formyl peptide receptor（FPR）） treatment, the expression of Glut1 and glucose uptake rate（GUR） of PMN were assayed by Western blot and enzymatic（glucose oxidase）methods. The directed migration of PMN toward hypoxia terminal was observed in oxygen gradient; the supernatant of cultured PMN under hypoxia induced chemotaxis in a time-dependent way, and the chemotaxis was intenser than that under normoxia. FPR antagonist t Boc attenuated partially the supernatant-induced chemotaxis. f MLP or hypoxia（1% O2） pretreatment increased the chemotaxis of PMN to serum and GUR. Hypoxia（3% O2） or f MLP pretreatment also upregulated the expression of glucose transporter 1（GLUT1）. These result indicated that hypoxia promotes PMN to produce chemoattractants such FPR agonists, which then induce PMN migrate to hypoxia terminal. The chemoattractants also can enhance the capability of PMN to resist hypoxia by utilizing glucose.

关 键 词：缺氧 白细胞 趋化 甲酰肽受体 

分 类 号：R363[医药卫生—病理学]