Background Current prosthetic, small diameter vascular grafts showing poor long term patency rates have led to the pursuit of other biological materials. Biomaterials that successfully integrate into surrounding tissu...Background Current prosthetic, small diameter vascular grafts showing poor long term patency rates have led to the pursuit of other biological materials. Biomaterials that successfully integrate into surrounding tissue should match not only the mechanical properties of tissues, but also topography. Polyglycolic acid (70130) has been used as synthetic grafts to determine whether human vascular smooth muscle cells and endothelial cells attach, survive and secrete endothelin and 6-keto-prostaglandin F1α (6-keto-PGF1α). Methods Endothelial cells and smooth muscle cells were isolated from adult human great saphenous vein. They were seeded on polyglycolic acid scaffold in vitro separately to grew vascular patch (Groups A and B respectively) and cocultured in vitro to grow into vascular patch (Group C). Smooth muscle cells and endothelial cells were identified by immunohistochemical analysis and growth of cells on polyglycolic acid was investigated using scanning electron microscopy. The levels of endothelin and 6-keto-PGF1α in the culturing solutions were examined by radioimmunology to measure endothelial function. Results Seed smooth muscle cells adhered to polyglycolic acid scaffold and over 28 days grew in the interstices to form a uniform cell distribution throughout the scaffold. Then seed endothelial cells formed a complete endothelial layer on the smooth muscle cells. The levels of endothelin and 6-keto-prostaglandin F1 alpha in the culturing solution were (234±29) pg/ml and (428±98) pg/ml respectively in Group C and (196±30) pg/ml and (346±120) pg/ml in Group B; both significantly higher than in Groups A and D (blank control group, all P〈0.05 ). Conclusions Cells could be grown successfully on polyglycolic acid and retain functions of secretion. Our next step is to use human saphenous vein smooth muscle cells and endothelial cells to grow tubular vascular grafts in vitro.展开更多
Background Endothelial progenitor cells (EPCs) are used in vascular tissue engineering and clinic therapy. Some investigators get EPCs from the peripheral blood for clinic treatment, but the number of EPCs is seldom...Background Endothelial progenitor cells (EPCs) are used in vascular tissue engineering and clinic therapy. Some investigators get EPCs from the peripheral blood for clinic treatment, but the number of EPCs is seldom enough. We have developed the cultivation and purification of EPCs from the bone marrow of children with congenital heart disease, to provide enough seed cells for a small calibre vascular tissue engineering study. Methods The 0.5-ml of bone marrow was separated from the sternum bone, and 5-ml of peripheral blood was collected from children with congenital heart diseases who had undergone open thoracic surgery. CD34+ and CD34+NEGFR+ cells in the bone marrow and peripheral blood were quantified by flow cytometry. CD34+/VEGFR+ cells were defined as EPCs. Mononuclear cells in the bone marrow were isolated by Ficoll density gradient centrifugation and cultured by the EndoCult Liquid Medium KitTM. Colony forming endothelial cells was detected. Immunohistochemistry staining for Dil-ac-LDL and FITC-UEA-1 confirmed the endothelial lineage of these cells. Results CD34+ and CD34+NEGFR+ cells in peripheral blood were (0.07±0.05)% and (0.05±0.02)%, respectively. The number of CD34+ and CD34+/VEGFR+ cells in bone marrow were significantly higher than in blood, (4.41±1.47)% and (0.98±0.65)%, respectively (P 〈0.0001). Many colony forming units formed in the culture. These cells also expressed high levels of Dil-ac-LDL and FITC-UEA-I. Conclusion This is a novel and feasible approach that can cultivate and purify EPCs from the bone marrow of children with congenital heart disease, and provide seed cells for small calibre vascular tissue engineering.展开更多
基金a grant from the Capital Medical Development Scientific Research Fund(No.2002-306)
文摘Background Current prosthetic, small diameter vascular grafts showing poor long term patency rates have led to the pursuit of other biological materials. Biomaterials that successfully integrate into surrounding tissue should match not only the mechanical properties of tissues, but also topography. Polyglycolic acid (70130) has been used as synthetic grafts to determine whether human vascular smooth muscle cells and endothelial cells attach, survive and secrete endothelin and 6-keto-prostaglandin F1α (6-keto-PGF1α). Methods Endothelial cells and smooth muscle cells were isolated from adult human great saphenous vein. They were seeded on polyglycolic acid scaffold in vitro separately to grew vascular patch (Groups A and B respectively) and cocultured in vitro to grow into vascular patch (Group C). Smooth muscle cells and endothelial cells were identified by immunohistochemical analysis and growth of cells on polyglycolic acid was investigated using scanning electron microscopy. The levels of endothelin and 6-keto-PGF1α in the culturing solutions were examined by radioimmunology to measure endothelial function. Results Seed smooth muscle cells adhered to polyglycolic acid scaffold and over 28 days grew in the interstices to form a uniform cell distribution throughout the scaffold. Then seed endothelial cells formed a complete endothelial layer on the smooth muscle cells. The levels of endothelin and 6-keto-prostaglandin F1 alpha in the culturing solution were (234±29) pg/ml and (428±98) pg/ml respectively in Group C and (196±30) pg/ml and (346±120) pg/ml in Group B; both significantly higher than in Groups A and D (blank control group, all P〈0.05 ). Conclusions Cells could be grown successfully on polyglycolic acid and retain functions of secretion. Our next step is to use human saphenous vein smooth muscle cells and endothelial cells to grow tubular vascular grafts in vitro.
基金This study was supported by a grant from Science Foundation of Beijing Education Commission (No. KM200710025022).
文摘Background Endothelial progenitor cells (EPCs) are used in vascular tissue engineering and clinic therapy. Some investigators get EPCs from the peripheral blood for clinic treatment, but the number of EPCs is seldom enough. We have developed the cultivation and purification of EPCs from the bone marrow of children with congenital heart disease, to provide enough seed cells for a small calibre vascular tissue engineering study. Methods The 0.5-ml of bone marrow was separated from the sternum bone, and 5-ml of peripheral blood was collected from children with congenital heart diseases who had undergone open thoracic surgery. CD34+ and CD34+NEGFR+ cells in the bone marrow and peripheral blood were quantified by flow cytometry. CD34+/VEGFR+ cells were defined as EPCs. Mononuclear cells in the bone marrow were isolated by Ficoll density gradient centrifugation and cultured by the EndoCult Liquid Medium KitTM. Colony forming endothelial cells was detected. Immunohistochemistry staining for Dil-ac-LDL and FITC-UEA-1 confirmed the endothelial lineage of these cells. Results CD34+ and CD34+NEGFR+ cells in peripheral blood were (0.07±0.05)% and (0.05±0.02)%, respectively. The number of CD34+ and CD34+/VEGFR+ cells in bone marrow were significantly higher than in blood, (4.41±1.47)% and (0.98±0.65)%, respectively (P 〈0.0001). Many colony forming units formed in the culture. These cells also expressed high levels of Dil-ac-LDL and FITC-UEA-I. Conclusion This is a novel and feasible approach that can cultivate and purify EPCs from the bone marrow of children with congenital heart disease, and provide seed cells for small calibre vascular tissue engineering.