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Background: The ability of mesenchymal stem cells (MSCs) to differentiate into many cell types, and modulate immune responses, makes them an attractive therapeutic tool for cell transplantation and tissue engineering.Objective: This project was designed for isolation, culture, and characterization of human marrow-derived MSCs based on the immunophenotypic markers and the differentiation potential.Methods: Bone marrow of healthy donors was aspirated from the iliac crest. Mononuclear cells were layered over the Ficoll-Paque density-gradient and plated in tissue cultures dish. The adherent cells expanded rapidly and maintained with periodic passages until a relatively homogeneous population was established. The identification of adherent cells and the immune-surface markers was performed by flow cytometric analysis at the third passage. The in vitro differentiation of MSCs into osteoblast and adipocytes was also achieved.Results: The MSCs were CD11b (CR3), CD45, CD34, CD31 (PCAM-1), CD40, CD80 (B7-1), and HLA-class II negative because antigen expression was less than 5%, while they showed a high expression of CD90, and CD73. The differentiation of osteoblasts, is determined by deposition of a mineralized extracellular matrix in the culture plates that can be detected with Alizarin Red. Adipocytes were easily identified by their morphology and staining with Oil Red.Conclusion: MSCs can be isolated and expanded from most healthy donors, providing for a source of cell-based therapy.

Background: Cell-based therapy has been implicated in the treatment of liver diseases. Mesenchymal stem cells from various sources such as bone marrow are available. These cells are one of the major candidates in cell therapy. The production of insulin-like growth factor-I increases in the regenerating organ. The insulin-like growth factor-I in liver regeneration is effective after binding to insulin-like growth factor-I receptor. Objective: To test our hypothesis that tumor necrosis factor-α can stimulate mesenchymal stem cells to express insulin-like growth factor-I receptor. Methods: Bone marrow was aspirated from normal human donor after taking informed consent. Cells were isolated and cultured. Identification of cells was done by flowcytometry and functional tests. The fourth passage cells were treated with tumor necrosis factor-α at two doses of 1 and 10 ng/mL, and incubated for 2, 10, 24, and 48 hours. Insulin-like growth factor-I receptor gene expression was studied using real-time polymerase chain reaction. Results: Flowcytometry showed that the human bone marrow mesenchymal stem cells were positive for CD90 and negative for CD45 and CD80. The insulin-like growth factor-I receptor gene expression was increased in tumor necrosis factor-α treated in comparison with untreated cells. Conclusion: Treatment of human bone marrow-derived mesenchymal stem cells with tumor necrosis factor-α increases gene expression of insulin-like growth factor-I receptor. This finding may be used for increasing the effectiveness of stem cell therapy in those with acute hepatic failure.

Background: Cell-based therapy has been implicated in the treatment of liver diseases. Mesenchymal stem cells from various sources such as bone marrow are available. These cells are one of the major candidates in cell therapy. The production of insulin-like growth factor-I increases in the regenerating organ. The insulin-like growth factor-I in liver regeneration is effective after binding to insulin-like growth factor-I receptor. Objective: To test our hypothesis that tumor necrosis factor-α can stimulate mesenchymal stem cells to express insulin-like growth factor-I receptor. Methods: Bone marrow was aspirated from normal human donor after taking informed consent. Cells were isolated and cultured. Identification of cells was done by flowcytometry and functional tests. The fourth passage cells were treated with tumor necrosis factor-α at two doses of 1 and 10 ng/mL, and incubated for 2, 10, 24, and 48 hours. Insulin-like growth factor-I receptor gene expression was studied using real-time polymerase chain reaction. Results: Flowcytometry showed that the human bone marrow mesenchymal stem cells were positive for CD90 and negative for CD45 and CD80. The insulin-like growth factor-I receptor gene expression was increased in tumor necrosis factor-α treated in comparison with untreated cells. Conclusion: Treatment of human bone marrow-derived mesenchymal stem cells with tumor necrosis factor-α increases gene expression of insulin-like growth factor-I receptor. This finding may be used for increasing the effectiveness of stem cell therapy in those with acute hepatic failure. [ABSTRACT FROM AUTHOR]

Background: The ability of mesenchymal stem cells (MSCs) to differentiate into many cell types, and modu-late immune responses, makes them an attractive therapeutic tool for cell transplantation and tissue engineering. Objective: This project was designed for isolation, culture, and characterization of human marrow-derived MSCs based on the immunophenotypic markers and the differentiation potential. Methods: Bone marrow of healthy donors was aspirated from the iliac crest. Mononuclear cells were layered over the Ficoll-Paque density-gradient and plated in tissue cultures dish. The adherent cells expanded rapidly and maintained with periodic passages until a relatively homogeneous population was established. The identification of adherent cells and the immune-surface markers was performed by flow cytometric analysis at the third passage. The in vitro differentiation of MSCs into osteoblast and adipocytes was also achieved. Results: The MSCs were CD11b (CR3), CD45, CD34, CD31 (PCAM-1), CD40, CD80 (B7-1), and HLA-class II negative because antigen expression was less than 5%, while they showed a high expression of CD90, and CD73. The differentiation of osteoblasts, is determined by deposition of a mineralized extracellular matrix in the culture plates that can be detected with Alizarin Red. Adipocytes were easily identified by their morphology and staining with Oil Red. Conclusion: MSCs can be isolated and expanded from most healthy donors, providing for a source of cell-based therapy. [ABSTRACT FROM AUTHOR]