IL-21 is a common chain cytokine regulating many cell types of the immune system. The IL-21 receptor (IL-21R) activates the JAK/STAT signaling pathway and is expressed on T, B, and natural killer (NK) cells. • Plays an important role in the development of humoral immunity through its effects on B cell biology including differentiation, affinity maturation, and memory responses • Regulates T cell responses including survival of CD8+ T cells and inhibition of Treg cells. IL-21 plays a pivotal role in Hodgkin’s lymphoma and suppresses contact hypersensitivity reactions • Promotes a less differentiated phenotype of CAR T cells while promoting the effector functions of the engineered cells The biological activity of CTGrade GMP interleukins and growth factors is standardized, where applicable, to WHO International standards, providing cell and gene therapy developers consistent, lot-to-lot biological activity and performance.
Bioactivity Assay:Proliferation of B9 cell ; ED50 =5 ng/mL; Bioactivity =WHO standard not available