Matrix metalloproteinase-9 regulates the shedding of CD73 from retinal pigment epithelium
10.3760/cma.j.issn.1005-1015.2017.05.018
- VernacularTitle:基质金属蛋白酶-9调控CD73自视网膜色素上皮细胞膜表面脱落机制的初步研究
- Author:
Fanqiang KONG
1
;
Shumin ZHOU
;
Song CHEN
Author Information
1. 300052,天津医科大学附属总医院检验科
- Keywords:
Matrix metalloproteinase 9/antagonists &inhibitors;
5'-Nucleotidase;
Retinal pigment epithelium
- From:
Chinese Journal of Ocular Fundus Diseases
2017;33(5):518-522
- CountryChina
- Language:Chinese
-
Abstract:
Objective To study how CD73 is shed from the retinal pigment epithelium (RPE) surface. Methods CD73 shedding was induced by treating RPE with lipopolysaccharides (LPS) and TNF-α. After Phospholipase C (PLC) or pan matrix metalloproteinase (MMP) inhibitors were added, surface amount of CD73 was evaluated by flow cytometry (FACS). Then selective inhibitors or their corresponding siRNAs of MMP-2 and MMP-9 were applied to the treatments of RPE; and their effects on induced CD73 shedding were evaluated by FACS. By site directed mutagenesis, mutations were introduced to Lys547-Phe548 coding sites of CD73 cDNA, which was cloned in a pcDNA mammalian expression vector. Both wt-CD73 and mutated-CD73 were over expressed in CD73-/- RPE and their induced shedding was compared. Results LPS and TNF-α induced CD73 shedding from RPE was completely blocked by the addition of pan MMP inhibitor but not PLC inhibitor. Selective MPP-9, but not MMP-2, inhibitor or its siRNA blocked CD73 shedding. In CD73-/- RPE induced CD73 shedding was happened to overexpressed wt-CD73 but not Lys547-Phe548 sites mutant CD73. Conclusion MMP-9 is responsible for shedding CD73 from RPE through hydrolyzing its Lys547 -Phe548 sites.
