Objective:To investigate the feasibility of bone marrow stromal cells (BMSCs) differenti ating into cardiomyocyte like cells in heterogeneous cardiomyocytes microenvironment in vitro. Methods: Mouse GFP-BMSCs were...Objective:To investigate the feasibility of bone marrow stromal cells (BMSCs) differenti ating into cardiomyocyte like cells in heterogeneous cardiomyocytes microenvironment in vitro. Methods: Mouse GFP-BMSCs were isolated by centrifugation through a Ficoll step gradient and purified by plating culture and depletion of the non-adherent cells. Neonatal rat cardiomyocytes (CMs) were isolated by enzymatic dissociation from hearts of 1-to 2-day old Sprague-Dawley (SD) rats and differentially plated to remove fibroblasts. Mouse GFP-BMSCs were cocuhured with neonatal rat CMs through direct and indirect contact, respectively. Cardiomyogenic differentiation of BMSCs was evaluated by immunostaining with an- ti-a-actin monoclonal antibody and observing synchronous contraction with adjacent CMs by phase contrast microphotography. Results: On day 7 of cocuhure, GFP-BMSCs (CMs : BMSCs:4 : 1)attached to nonfluorescent contracting cells (rat-derived CMs) showed myotube-like formation and started to contract synchronously with adjacent cardiomyocytes. About 10% of the fluorescent GFP-BMSCs were cardiomyocyte-like cells as determined by cell morphology and positive actin staining. Conclusion;Direct cell to-cell interaction with CMs is crucial for cardiomyogenic differentiation of BMSCs in heterogeneous CMs microenvironment in vitro. This provides a novel inducing pathway for directional differentiation of cardiovascular tissue engineering seed cells.展开更多
Objective: To explore the effect of gamma irradiation on nuclear factor-kappa B in cultured bone marrow stromal cells. Methods: Immunocytochemistry, Western blot and electrophoretic mobility shift assay (EMSA) were us...Objective: To explore the effect of gamma irradiation on nuclear factor-kappa B in cultured bone marrow stromal cells. Methods: Immunocytochemistry, Western blot and electrophoretic mobility shift assay (EMSA) were used. Results: The expression of NF-kB in cultured mouse bone marrow stromal cells (BM-SCs) on the level of protein was elevated after exposure to 60Co in the dosage of 8. 0 Gy with the use of im-munocytochemistry and Western blot. The activity of nuclear factor-kappa B in cultured BMSCs was significantly increased after exposure to gamma irradiation by using EMSA. The activity peak was at the 4th h after irradiation. Conclusion: Our results suggest that the activation of nuclear factor-kappa B in the BMSCs after irradiation may be involved in the protection of BMSCs against apoptosis and in the recovery of hematopoiesis after radiation.展开更多
文摘Objective:To investigate the feasibility of bone marrow stromal cells (BMSCs) differenti ating into cardiomyocyte like cells in heterogeneous cardiomyocytes microenvironment in vitro. Methods: Mouse GFP-BMSCs were isolated by centrifugation through a Ficoll step gradient and purified by plating culture and depletion of the non-adherent cells. Neonatal rat cardiomyocytes (CMs) were isolated by enzymatic dissociation from hearts of 1-to 2-day old Sprague-Dawley (SD) rats and differentially plated to remove fibroblasts. Mouse GFP-BMSCs were cocuhured with neonatal rat CMs through direct and indirect contact, respectively. Cardiomyogenic differentiation of BMSCs was evaluated by immunostaining with an- ti-a-actin monoclonal antibody and observing synchronous contraction with adjacent CMs by phase contrast microphotography. Results: On day 7 of cocuhure, GFP-BMSCs (CMs : BMSCs:4 : 1)attached to nonfluorescent contracting cells (rat-derived CMs) showed myotube-like formation and started to contract synchronously with adjacent cardiomyocytes. About 10% of the fluorescent GFP-BMSCs were cardiomyocyte-like cells as determined by cell morphology and positive actin staining. Conclusion;Direct cell to-cell interaction with CMs is crucial for cardiomyogenic differentiation of BMSCs in heterogeneous CMs microenvironment in vitro. This provides a novel inducing pathway for directional differentiation of cardiovascular tissue engineering seed cells.
基金Supported by the "Ninth Five" Obligatory Budget of PLA. No. 96L045
文摘Objective: To explore the effect of gamma irradiation on nuclear factor-kappa B in cultured bone marrow stromal cells. Methods: Immunocytochemistry, Western blot and electrophoretic mobility shift assay (EMSA) were used. Results: The expression of NF-kB in cultured mouse bone marrow stromal cells (BM-SCs) on the level of protein was elevated after exposure to 60Co in the dosage of 8. 0 Gy with the use of im-munocytochemistry and Western blot. The activity of nuclear factor-kappa B in cultured BMSCs was significantly increased after exposure to gamma irradiation by using EMSA. The activity peak was at the 4th h after irradiation. Conclusion: Our results suggest that the activation of nuclear factor-kappa B in the BMSCs after irradiation may be involved in the protection of BMSCs against apoptosis and in the recovery of hematopoiesis after radiation.