The differentiation of CD4⁺ T cells is affected by both cytokine and antigen dose.

<p>OT-II lines were generated by repeated weekly stimulation in the presence of cytokine that polarized the cells toward differentiation into Th1, Th2 or Th17 cells together with high (10⁻⁵M), intermediate (10⁻⁷M) or low (10⁻⁹M) concentrations of peptide. Established OT-II cell lines were assayed for cytokine production following stimulation with OVA_323–339 peptide (10⁻⁴M). The differentiation state of the cell lines was determined by measuring the production of IFN-γ (Th1), IL-4 (Th2) or IL-17 (Th17). A. Representative dotplots of cytokine production for each cell line are shown. Data shown are gated on CD4⁺CD45.2⁺ cells. B. The percentage of cells that produce cytokine following peptide stimulation is shown for each stimulation condition. Th17 cells did not survive on low dose peptide. Data are the average of independently generated lines: −5M Th1 (n = 3), −7M Th1 (n = 3), −9M Th1 (n = 4), −5M Th2 (n = 3), −7M Th2 (n = 3), −9M Th2 (n = 3), −5M Th17 (n = 4), −7M Th17 (n = 3), and −9M Th17 (n = 2). * p≤0.05, *** p≤0.0005.