Objective To investigate the possible involvement of erythropoietin (EPO)/erythropoietin receptor (EPOR) system in neovascularization and vascular regeneration in diabetic retinopathy (DR). Methods EPOR positive...Objective To investigate the possible involvement of erythropoietin (EPO)/erythropoietin receptor (EPOR) system in neovascularization and vascular regeneration in diabetic retinopathy (DR). Methods EPOR positive circulating progenitor cells (CPCs: CD34^+) and endothelial progenitor cells (EPCs: CD34^+KDR^+) were assessed by flow cytometry in type 2 diabetic patients with different stages of DR. The cohort consisted of age- and sex-matched control patients without diabetes (n=7), non-prolif- erative DR (NPDR, n=7), proliferative DR (PDR, n=8), and PDR complicated with diabetic nephropathy (PDR-DN, n=7). Results The numbers of EPOR^+ CPCs and EPOR^+ EPCs were reduced remarkably in NPDR corn pared with the control group (both P(0.01), whereas rebounded in PDR and PDR-DN groups in varying degrees. Similar changes were observed in respect of the proportion of EPOR^+ CPCs in CPCs (NPDR vs. control, P(0.01) and that of EPOR^+ EPCs in EPCs (NPDR vs. control, P〈0.05). Conclusion Exogenous EPO, mediated via the EPO/EPOR system of EPCs, may alleviate the impaired vascular regeneration in NPDR, whereas it might aggravate retinal neovascularization in PDR due to a rebound of EPOR^+ EPCs associated with ischemia.展开更多
Plexiform lesions (PLs), which are often accompanied by perivascular infiltrates of mononuclear cells, represent the hallmark lesions of pulmonary arteries in humans suffering from severe pulmonary arterial hyperten...Plexiform lesions (PLs), which are often accompanied by perivascular infiltrates of mononuclear cells, represent the hallmark lesions of pulmonary arteries in humans suffering from severe pulmonary arterial hypertension (PAH). Endothelial progenitor cells (EPCs) have been recently implicated in the formation of PLs in human patients. PLs rarely develop in rodent animal models of PAH but can develop spontaneously in broiler chickens. The aim of the present study was to confirm the presence of EPCs in the PLs in broilers. The immune mechanisms involved in EPC dysfunction were also evaluated. Lungs were collected from commercial broilers at 1 to 4 weeks of age. The right/total ventricle ratios indicated normal pulmonary arterial pressures for all sampled birds. Immunohistochemistry was per- formed to determine the expressions of EPC markers (CD133 and VEGFR-2) and preangiogenic molecule hepatocyte growth factor (HGF) in the lung samples. An EPC/lymphocyte co-culture system was used to investigate the functional changes of EPCs under the challenge of immune cells. PLs with different cellular composition were detected in the lungs of broilers regardless of age, and they were commonly surrounded by moderate to dense perivascular mono- nuclear cell infiltrates. Immunohistochemical analyses revealed the presence of CD133* and VEGFR-2* cells in PLs. These structures also exhibited a strong expression of HGF. Lymphocyte co-culture enhanced EPC apoptosis and completely blocked HGF-stimulated EPC survival and in vitro tube formation. Taken together, this work provides evidence for the involvement of EPCs in the development of PLs in broilers. It is suggested that the local immune cell infiltrate might serve as a contributor to EPC dysfunction by inducing EPC death and limiting their response to angi- ogenic stimuli. Broiler chickens may be valuable for investigating reversibility of plexogenic arteriopathy using gene- modified inflammation-resistant EPCs.展开更多
基金Supported by Sciences and Technology Commission of Shanghai Municipality (08ZR1422100 and 08410701200)
文摘Objective To investigate the possible involvement of erythropoietin (EPO)/erythropoietin receptor (EPOR) system in neovascularization and vascular regeneration in diabetic retinopathy (DR). Methods EPOR positive circulating progenitor cells (CPCs: CD34^+) and endothelial progenitor cells (EPCs: CD34^+KDR^+) were assessed by flow cytometry in type 2 diabetic patients with different stages of DR. The cohort consisted of age- and sex-matched control patients without diabetes (n=7), non-prolif- erative DR (NPDR, n=7), proliferative DR (PDR, n=8), and PDR complicated with diabetic nephropathy (PDR-DN, n=7). Results The numbers of EPOR^+ CPCs and EPOR^+ EPCs were reduced remarkably in NPDR corn pared with the control group (both P(0.01), whereas rebounded in PDR and PDR-DN groups in varying degrees. Similar changes were observed in respect of the proportion of EPOR^+ CPCs in CPCs (NPDR vs. control, P(0.01) and that of EPOR^+ EPCs in EPCs (NPDR vs. control, P〈0.05). Conclusion Exogenous EPO, mediated via the EPO/EPOR system of EPCs, may alleviate the impaired vascular regeneration in NPDR, whereas it might aggravate retinal neovascularization in PDR due to a rebound of EPOR^+ EPCs associated with ischemia.
基金Project supported by the Zhejiang Provincial Natural Science Foundation of China(No.LR12C18001)
文摘Plexiform lesions (PLs), which are often accompanied by perivascular infiltrates of mononuclear cells, represent the hallmark lesions of pulmonary arteries in humans suffering from severe pulmonary arterial hypertension (PAH). Endothelial progenitor cells (EPCs) have been recently implicated in the formation of PLs in human patients. PLs rarely develop in rodent animal models of PAH but can develop spontaneously in broiler chickens. The aim of the present study was to confirm the presence of EPCs in the PLs in broilers. The immune mechanisms involved in EPC dysfunction were also evaluated. Lungs were collected from commercial broilers at 1 to 4 weeks of age. The right/total ventricle ratios indicated normal pulmonary arterial pressures for all sampled birds. Immunohistochemistry was per- formed to determine the expressions of EPC markers (CD133 and VEGFR-2) and preangiogenic molecule hepatocyte growth factor (HGF) in the lung samples. An EPC/lymphocyte co-culture system was used to investigate the functional changes of EPCs under the challenge of immune cells. PLs with different cellular composition were detected in the lungs of broilers regardless of age, and they were commonly surrounded by moderate to dense perivascular mono- nuclear cell infiltrates. Immunohistochemical analyses revealed the presence of CD133* and VEGFR-2* cells in PLs. These structures also exhibited a strong expression of HGF. Lymphocyte co-culture enhanced EPC apoptosis and completely blocked HGF-stimulated EPC survival and in vitro tube formation. Taken together, this work provides evidence for the involvement of EPCs in the development of PLs in broilers. It is suggested that the local immune cell infiltrate might serve as a contributor to EPC dysfunction by inducing EPC death and limiting their response to angi- ogenic stimuli. Broiler chickens may be valuable for investigating reversibility of plexogenic arteriopathy using gene- modified inflammation-resistant EPCs.