In Vitro Human Haematopoietic Stem Cell Expansion and Differentiation

Abstract

The haematopoietic system plays an essential role in our health and survival. It is comprised of a range of mature blood and immune cell types, including oxygen-carrying erythrocytes, platelet-producing megakaryocytes and infection-fighting myeloid and lymphoid cells. Self-renewing multipotent haematopoietic stem cells (HSCs) and a range of intermediate haematopoietic progenitor cell types differentiate into these mature cell types to continuously support haematopoietic system homeostasis throughout life. This process of haematopoiesis is tightly regulated in vivo and primarily takes place in the bone marrow. Over the years, a range of in vitro culture systems have been developed, either to expand haematopoietic stem and progenitor cells or to differentiate them into the various haematopoietic lineages, based on the use of recombinant cytokines, co-culture systems and/or small molecules. These approaches provide important tractable models to study human haematopoiesis in vitro. Additionally, haematopoietic cell culture systems are being developed and clinical tested as a source of cell products for transplantation and transfusion medicine. This review discusses the in vitro culture protocols for human HSC expansion and differentiation, and summarises the key factors involved in these biological processes.

The influence of redox modulation on hypoxic endothelial cell metabolic and proteomic profiles through a small thiol‐based compound tuning glutathione and thioredoxin systems

“…When these cells are exposed to atmospheric levels of oxygen (~21% O 2 ), HSCs rapidly begin the process of differentiation 66 . Likewise, in hypoxic conditions, the direct application of recombinant cytokines cocktails trying to mimic the BM micro‐environment has limited success in HSC expansion 67 . Recent efforts have therefore focused on the use of cells, in co‐culture with HSCs, able to sustain their maintenance in vitro 68 …”

“…66 Likewise, in hypoxic conditions, the direct application of recombinant cytokines cocktails trying to mimic the BM micro-environment has limited success in HSC expansion. 67 Recent efforts have therefore focused on the use of cells, in co-culture with HSCs, able to sustain their maintenance in vitro. 68 This study is focused on a pivotal component of the vascular system, the ECs, to investigate cellular behavior and the influence of redox modulation on cell metabolic activity/function.…”

Hematopoietic stem cell collection for sickle cell disease gene therapy

“…Several new drugs that have been shown to improve HSC mobilization for cancer therapy are likely to improve HSC yields in SCD. A complementary strategy may be to reduce the required yields by utilizing emerging methods for ex vivo HSC expansion during DP manufacturing [102,103,104 ▪ ,105]. In the future, efforts to optimize HSC mobilization are likely to facilitate “in vivo” gene therapies by overcoming the challenges of targeting HSCs within the BM space [94,106–109].…”

HIV-1 infection of genetically engineered iPSC-derived central nervous system-engrafted microglia in a humanized mouse model

“…The iPSCs were differentiated into hematopoietic progenitor cells (HPCs) using a commercially available STEMdiff Hematopoietic kit as per published protocols (Figure 1A) (43)(44)(45)(46)(47). The development of HPCs from iPSCs requires a combination of growth factors, cytokines, and small molecules, which include stem cell factor (SCF), Flt3 Ligand (Flt3L), Thrombopoietin (TPO), IL-3, IL-6, and Granulocyte Macrophage Colony-Stimulating Factor (GM-CSF) (48,49).…”