IL-21 is the primary common ? chain-binding cytokine required for human B-cell differentiation in vivo.

Recher M, Berglund LJ, Avery DT, Cowan MJ, Gennery AR, Smart J, Peake J, Wong M, Pai SY, Baxi S, Walter JE, Palendira U, Tangye GA, Rice M, Brothers S, Al-Herz W, Oettgen H, Eibel H, Puck JM, Cattaneo F, Ziegler JB, Giliani S, Tangye SG, Notarangelo LD