Hematopoietic Stem Cell-Based Cell and Gene Therapy Beyond Monogenic Diseases

Hematopoietic stem cells (HSCs) are multipotent stem cells capable of differentiating into all types of blood and immune progeny and endowed with self-renewal capacity to enable lifelong hematopoiesis. Based on these unique characteristics, HSCs are utilized as a cell source for cell and gene therapies. During its dawning period, HSC-based therapies faced significant challenges due to inefficient gene transfer and insertional leukemogenesis. However, technological advances, such as the use of HIV-derived lentiviral vectors and cellular promoters, have established HSC gene therapy as a powerful treatment modality for patients with congenital monogenic diseases, leading to approved therapies commercially available in Europe and the United States. HSC-based therapies are now being explored for broader indications, including cancer, autoimmune, and infectious diseases. Innovative concepts achievable with HSCs-such as delivering therapeutic proteins to hard-to-reach tissues, in vivo delivery of antibodies and immune cells, and molecular shielding-have been proposed, offering new therapeutic approaches. Moreover, technological innovations in related fields, including more precise gene expression control and reduced-toxicity bone marrow conditioning, are expanding the range of applications. HSC-based cell and gene therapies are therefore evolving into a therapeutic modality applicable beyond monogenic diseases to a broader range of indications, to provide therapeutic value to patients with intractable diseases.