Signaling pathway of IL-15 begins with binding to IL-15Rα receptor, with subsequent presentation to surrounding cells bearing IL-15Rβγc complex on their cell surface. Upon binding IL-15β subunit activates Janus kinase 1+ (Jak1+) and γc subunit Janus kinase 3+ (Jak3+), which leads to phosphorylation+ and activation of signal transducer and activator of transcription 3+ (STAT3+) and STAT5+. Due to sharing of receptor+ subunits between IL-2+ and IL-15, both of these cytokine+s have similar downstream effects including the induction of B-cell lymphoma+ (Bcl-2+), MAP+ (mitogen-activated protein kinase+) kinase pathway and the phosphorylation of Lck (lymphocyte-activated protein tyrosine kinase) and Syk (spleen tyrosine kinase) kinases, which leads to cell proliferation and maturation (Figure 5).