Aim: Inflammatory myeloid lineage cells mediate neotissue formation in tissue-engineered vascular grafts, but the molecular mechanism is not completely understood. We examined the role of vasculogenic PDGF-B in tissue-engineered vascular graft neotissue development.
Materials & methods: Myeloid cell-specific PDGF-B knockout mice (PDGF-KO) were generated using bone marrow transplantation, and scaffolds were implanted as inferior vena cava interposition grafts in either PDGF-KO or wild-type mice.
Results: After 2 weeks, grafts from PDGF-KO mice had more remaining scaffold polymer and less intimal neotissue development. Increased macrophage apoptosis, decreased smooth muscle cell proliferation and decreased collagen content was also observed.
Conclusion: Myeloid cell-derived PDGF contributes to vascular neotissue formation by regulating macrophage apoptosis, smooth muscle cell proliferation and extracellular matrix deposition.
Keywords: TEVG; extracellular matrix; macrophage; myeloid cell; neotissue development; platelet-derived growth factor; scaffold degradation; smooth muscle cell; tissue-engineered vascular graft.