Table I.

Treatment of T cells with IL-2, IL-7, and IL-15 but not IL-4 and IL-21, leads to up-regulation of IL-2Rα chain^a

	Media		IL-2		IL-4		IL-7		IL-15		IL-21
	Isotype	Anti-CD25	Isotype	Anti-CD25	Isotype	Anti-CD25	Isotype	Anti-CD25	Isotype	Anti-CD25	Isotype	Anti-CD25
Anti-CD3	3.44	96.75	5.35	736.86	3.5	94.12	5.31	622.07	4.69	488.4	4.16	100.12
Anti-CD3/PD-L1.Fc	3.12	46.38	4.49	307.03	4.05	51.41	4.18	246.99	4.46	272	4.34	51.42

a CD4⁺ T cells were activated with anti-CD3 Ab-coated microspheres in the presence of optimal concentrations of the indicated cytokines. At 72 h, cells were harvested and stained for IL-2Rα (CD25) expression as described in Materials and Methods (n = 2). Mean fluorescence values are shown, bold numbers indicate increases 4-fold above media control.