The invention provides novel methods of reducing transplant rejection and cardiac allograft vasculopathy in humans by employing the implantation of autologous progenitor cells into the transplanted donor heart. The autologous progenitor cells can be vascular progenitor cells (VPCs) and/or myocyte progenitor cells (MPCs) isolated from the recipients explanted heart. Alternatively, bone marrow progenitor cells (BMPCs) isolated from the recipient may also be used.