DLL4 and VCAM1 enhance the emergence of T cell–competent hematopoietic progenitors from human pluripotent stem cells

Abstract

T cells show tremendous efficacy as cellular therapeutics. However, obtaining primary T cells from human donors is expensive and variable. Pluripotent stem cells (PSCs) have the potential to provide a renewable source of T cells, but differentiating PSCs into hematopoietic progenitors with T cell potential remains an important challenge. Here, we report an efficient serum- and feeder-free system for differentiating human PSCs into hematopoietic progenitors and T cells. This fully defined approach allowed us to study the impact of individual proteins on blood emergence and differentiation. Providing DLL4 and VCAM1 during the endothelial-to-hematopoietic transition enhanced downstream progenitor T cell output by ~80-fold. These two proteins synergized to activate notch signaling in nascent hematopoietic stem and progenitor cells, and VCAM1 additionally promoted an inflammatory transcriptional program. We also established optimized medium formulations that enabled efficient and chemically defined maturation of functional CD8αβ + , CD4 − , CD3 + , TCRαβ + T cells with a diverse TCR repertoire.

‘Off the shelf’ immunotherapies: Generation and application of pluripotent stem cell‐derived immune cells

“…41,[48][49][50][51] More recently, Michaels et al established a serumand feeder-free differentiation system with the addition of DLL4 and VCAM1 during the endothelial-to-haematopoietic transition, which promoted T cell production by approximately 80-fold. 52 Furthermore, the 3D-organoid systems, such as artificial thymic organoid (ATO) and fetal thymic organ culture systems, were established for the generation of mature T cells derived from PSCs. 16,51,[53][54][55][56] In particular, the ATO-based differentiation system was used to induce T-iPSCs derived from CD62L + naive and memory T cells into CD8αβ + T cells.…”

“…Because the TCR gene of a T‐iPSC clone has been rearranged to be antigen‐specific, all T cells obtained from differentiation of this iPSC line bear a specific rearranged TCR originated from the T‐iPSC clone that is identical to the original T cell and respond specifically to the original epitope 41,48–51 . More recently, Michaels et al established a serum‐ and feeder‐free differentiation system with the addition of DLL4 and VCAM1 during the endothelial‐to‐haematopoietic transition, which promoted T cell production by approximately 80‐fold 52 …”

“… 41 , 48 , 49 , 50 , 51 More recently, Michaels et al established a serum‐ and feeder‐free differentiation system with the addition of DLL4 and VCAM1 during the endothelial‐to‐haematopoietic transition, which promoted T cell production by approximately 80‐fold. 52 …”

Stem cell-based multi-tissue platforms to model human autoimmune diabetes

“…For example, the use of serum as well as the choice of cell of origin for reprogramming (e.g. T cells, which have a pre-arranged TCR, vs other cell types) can cause variability in T cell differentiation potential [ 106 , 107 ]. The yield of T cells produced from pluripotent stem cells is also lower than when using cord blood cells as starting material [ 107 ] while requirement for stromal feeders complicates our ability to produce large amounts of SC-T cells.…”

“…T cells, which have a pre-arranged TCR, vs other cell types) can cause variability in T cell differentiation potential [ 106 , 107 ]. The yield of T cells produced from pluripotent stem cells is also lower than when using cord blood cells as starting material [ 107 ] while requirement for stromal feeders complicates our ability to produce large amounts of SC-T cells. However, recent studies have described alternative approaches using microbeads or immobilized Notch ligands that supports the development of SC-T cells, avoiding the need for stromal cells [ 106 , 108 ].…”