Multiplexed iPSC platform for advanced NK cell immunotherapies

Abstract

Human pluripotent stem cell (PSC) derivation advances have revealed enormous potential for improved cancer immunotherapy and clinical-scale blood cell production. PSCs can self-renew indefinitely and be differentiated into specialized cells, making them promising candidates for producing cytotoxic lymphocytes. Deriving natural killer (NK) cells from PSCs unlocks new possibilities for studying developmental hematopoiesis and investigating potential immunotherapy treatments. Cellular therapies, combined with genetic engineering, are potent tools for combating cancer and viral infections. While NK cells directly lyse tumor cells, genetic modifications, such as chimeric antigen receptor (CAR) engineering or the deletion of checkpoint molecules, can enhance their functional capacity. Here, we discuss recent advances in induced PSC (iPSC) editing and guided differentiation, focusing on developing NK cell immunotherapeutic products and optimizing iPSCs as an NK cell source to broaden therapeutic options and address diverse patient needs. This comprehensive review evaluates iPSC-derived NK cell-based therapies, recent advances, and future genome-editing strategies.

Keywords: chimeric antigen receptor; gene editing; genetic engineering; immunotherapy; induced pluripotent stem cells; natural killer cells.

Graphical abstract

Figure 1

Major roles and development of NK cells in humans (A) NK cells release cytotoxic proteins in response to interaction with stressed, malignant, or infected cells. NK cells can modulate adaptive immune cell abundance, maturity, and activity by secretion of IFN-γ and TNF-α. CD56^dim NK cells predominate peripheral blood NK cell populations and primarily perform cytolytic activity and immune surveillance. IL-15 secreted by multiple cell types can impact NK cell activity through Ras/Raf, PI3K, and JAK/STAT pathways. CD56^bright NK cells make up most NK cells residing in secondary lymphoid tissues, where they perform primarily immune-modulating functions. (B) Linear and non-linear models of human NK cell development. In the linear model, hematopoietic stem cells (HSCs) generate lymphoid-primed multipotent progenitors (MPPs), which differentiate into common lymphoid progenitors (CLPs) and then NK cell precursors (NKPs). These precursors mature sequentially into CD56^bright and CD56^dim NK cells, with adaptive NK cells emerging later in response to viral infection. The non-linear model suggests a more flexible developmental trajectory. HSCs still generate MPPs, but these can differentiate into either CLPs or common myeloid progenitors (CMPs), both capable of producing NKPs. CLPs predominantly give rise to CD56^bright NK cells, while CMPs tend to generate CD56^dim NK cells, both of which can ultimately differentiate into adaptive NK cells. This model underscores the growing recognition of NK cell heterogeneity and developmental plasticity in different physiological and disease settings.

Figure 2

Multiplexed iPSC platform for engineered iNK cell production (A) Schematic of the hematopoietic progenitors and iNK differentiation from engineered iPSCs. (B) Strategies for genetic modifications to improve iPSC-NK cell function. Several genetic alternations have been engineered to enhance the biology and function of iPSC-derived NK cells for immune therapeutics. Here, we highlighted key components that have been engineered into iPSCs to enhance the functionality of iNK cells.