Figure 4.

PGRN drives TGF-β secretion under the conditions of stimulation. CD4⁺ T lymphocytes were incubated with or without PHA in the presence or absence of indicated concentrations of PGRN for 5 days. TGF-β levels in the supernatants were measured by ELISA. Data are the means ± standard deviations of three experiments performed in triplicate. ^∗p < 0.05, ^∗∗p < 0.01, ^∗∗∗p < 0.001, or ns (not significant). Similar results were obtained in four independent experiments.