Interleukin-7 (IL-7) is a cytokine that promotes the differentiation of pluripotent hematopoietic stem cells (HSCs) into lymphoid progenitor cells and supports proliferation of various cells in the lymphoid lineage (B cells, T cells and NK cells). It is secreted mainly by stromal cells in the bone marrow and thymus and is used in the ex vivo expansion of genetically modified T cells, such as CAR T cells, and differentiation of induced pluripotent stem cells (iPSCs) into T cells. It is in addition used to differentiate cord blood derived hematopoietic stem cells (HSCs/CD34+) into NK cells.
