A novel strategy for allogeneic stem cell transplantation: perfusion method plus intra–bone marrow injection of stem cells

Using long bones of cynomolgus monkeys, we have recently developed a new “Perfusion Method (PM)” for harvesting bone marrow cells (BMCs) while minimizing the contamination of BMCs with T cells from the peripheral blood. When thus collected BMCs, which contain not only pluripotent hemopoietic stem cells (P-HSCs) but also mesenchymal stem cells (MSCs), are directly injected into the bone marrow cavity of recipients (intra–bone marrow BMT: “IBM-BMT”), the donor-derived hemopoietic cells quickly recover even when the radiation doses used as the conditioning regimen are reduced. Recipient mice, rats, and even monkeys show neither graft-vs-host disease (GVHD) nor graft failure. In this article, we discuss why this new method (PM + IBM-BMT) may become a valuable strategy for allogeneic stem cell (both P-HSC and MSC) transplantation.