Engineering the Hematopoietic Stem Cell Niche: Biomaterials and Drug Delivery Strategies for Ex Vivo Expansion and Transplantation

Hematopoietic stem cells reside within highly specialized bone marrow niches in which cellular interactions, extracellular matrix components, soluble factors, mechanical properties, and spatial organization collectively regulate stem cell quiescence, self-renewal, differentiation, and mobilization. Replicating these complex interactions outside the body remains a major challenge for effective HSC expansion and transplantation.Recent developments in biomaterials and bioengineering have enabled increasingly sophisticated approaches to mimic components of the hematopoietic microenvironment. Engineered matrices, hydrogels, three-dimensional culture systems, micro- and nanomaterials, and controlled delivery platforms can provide biochemical and biophysical signals with greater spatial and temporal precision. Integrating these technologies with emerging knowledge of HSC–niche interactions may enable improved ex vivo expansion and more effective transplantation strategies.Hematopoietic stem cell (HSC) transplantation is a potentially curative therapy for a wide range of hematological and immune disorders. However, its broader application remains limited by challenges including insufficient stem cell numbers, loss of stemness during ex vivo culture, variable engraftment, and difficulties in recreating the complex regulatory signals of the native bone marrow niche. Advances in biomaterials, tissue engineering, and controlled drug delivery provide new opportunities to address these limitations by creating engineered microenvironments that more precisely regulate HSC fate and function.This Research Topic aims to bring together interdisciplinary advances in HSC biology, biomaterials, drug delivery, tissue engineering, and transplantation. Particular emphasis will be placed on strategies that recreate or modulate key features of the hematopoietic niche to enhance HSC maintenance and expansion, improve transplantation outcomes, and facilitate the translation of engineered stem cell technologies toward clinical applications.We welcome Original Research, Review, Mini Review, Perspective, and other relevant article types addressing the engineering and therapeutic modulation of the hematopoietic stem cell niche.Topics of interest include, but are not limited to: • Biomaterials and engineered extracellular matrices for HSC culture and expansion • Hydrogels, scaffolds, and three-dimensional models of the bone marrow niche • Micro- and nanoscale platforms for regulating HSC behavior • Controlled delivery of cytokines, growth factors, small molecules, nucleic acids, or other bioactive agents • Engineering of cellular and molecular interactions within the HSC niche • Biophysical and mechanical regulation of HSC fate • Organoid, microfluidic, and organ-on-chip models of hematopoiesis • Strategies for maintaining HSC stemness during ex vivo expansion • Biomaterial- and drug delivery-based approaches to improve HSC homing, engraftment, and transplantation • Translational and preclinical approaches connecting engineered HSC niches with regenerative medicine and transplantationWe particularly encourage interdisciplinary contributions connecting fundamental HSC biology with biomaterials, bioengineering, drug delivery, and clinical transplantation. Topic editors: Hay Man Saung Hnin Soe, Peng Lyu Source: https://www.frontiersin.org/research-topics/86165/engineering-the-hematopoietic-stem-cell-niche-biomaterials-and-drug-delivery-strategies-for-ex-vivo-expansion-and-transplantation