Tissue engineering of heart valves by recellularization of glutaraldehyde-fixed porcine valves using bone marrow-derived cells.
To increase the biocompatibility and durability of glutaraldehyde (GA)-fixed valves, a biological coating with viable endothelial cells (ECs) has been proposed. However, stable EC layers have not been formed successfully on GA-fixed valves due to their inability to repopulate. In this study, to improve cellular adhesion and proliferation, the GA-fixed prostheses were detoxified by treatment with citric acid to remove free aldehyde groups. Canine bone marrow mononuclear cells (MNCs) were differentiated into EC-like cells and myofibroblast-like cells in vitro. Detoxified prostheses were seeded and recellularized with differentiated bone marrow- derived cells (BMCs) for seven days. Untreated GA-fixed prostheses were used as controls. Cell attachment, proliferation, metabolic activity, and viability were investigated and cell-seeded leaflets were histologically analyzed. On detoxified GA-fixed prostheses, BMC seeding resulted in uninhibited cell proliferation after seven days. In contrast, on untreated GA-fixed prostheses, cell attachment was poor and no viable cells were observed. Positive staining for smooth muscle a-actin, CD31, and proliferating cell nuclear antigen was observed on the luminal side of the detoxified valve leaflets, indicating differentiation and proliferation of the seeded BMCs. These results demonstrate that the treatment of GA-fixed valves with citric acid established a surface more suitable for cellular attachment and proliferation. Engineering heart valves by seeding detoxified GA-fixed biological valve prostheses with BMCs may increase biocompatibility and durability of the prostheses. This method could be utilized as a new approach for the restoration of heart valve structure and function in the treatment of end-stage heart valve disease.
Kim
Sang Soo
SS
Department of Bioengineering, Hanyang University, Seoul 133-791, Korea.
Lim
Sang Hyun
SH
Cho
Seung Woo
SW
Gwak
So Jung
SJ
Hong
Yoo Sun
YS
Chang
Byung Chul
BC
Park
Moon Hyang
MH
Song
Kang Won
KW
Choi
Cha Yong
CY
Kim
Byung Soo
BS
D000199:Actins / Q000032:analysis; D000818:Animals; D001854:Bone Marrow Cells / Q000737:chemistry / Q000502:physiology* / Q000648:ultrastructure; D002448:Cell Adhesion / Q000502:physiology; D018929:Cell Culture Techniques / Q000379:methods*; D002454:Cell Differentiation / Q000502:physiology; D049109:Cell Proliferation; D002470:Cell Survival / Q000502:physiology; D004285:Dogs; D042783:Endothelial Cells / Q000166:cytology / Q000502:physiology; D005976:Glutaral / Q000737:chemistry*; D006350:Heart Valve Prosthesis; D006351:Heart Valves / Q000166:cytology / Q000502:physiology*; D007150:Immunohistochemistry; D008855:Microscopy, Electron, Scanning; D009130:Muscle, Smooth / Q000737:chemistry; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000032:analysis; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis; D013552:Swine; D023822:Tissue Engineering / Q000379:methods*; D016707:Tissue Fixation
D000199:Actins; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D018809:Proliferating Cell Nuclear Antigen; D005976:Glutaral