Applications of human hematopoietic stem cells isolated and expanded from different tissues in regenerative medicine

Bone marrow transplantation is a well-established stem cell-based therapy for the management of malignant and nonmalignant hematological disorders. In addition to the bone marrow, therapeutic hematopoietic stem cells (HSCs) can also be obtained from umbilical cord blood and mobilized peripheral blood. Transplantation of HSCs isolated from these tissues can be carried out with or without prior enrichment of specific cell types. New methodologies have been developed for lineage-specific HSC expansion and their transplantation as a supplementary treatment to whole bone marrow transplantation. In this review we have described the current methodologies for isolating and processing HSCs from various tissues, and discussed strategies to generate sufficient and functional HSCs for clinical and preclinical applications by expansion ex vivo. The various disease conditions in which these cells could be used, and the methods for delivering the cells into patients, are also discussed.