Role of IFN-γ in induction of Foxp3 and conversion of CD4⁺ CD25^– T cells to CD4⁺ Tregs
J. Clin. Invest. Zhaojun Wang, et al. 116:2434 doi:10.1172/JCI25826 [Go to this article.]

Figure 5
Conversion of CD4⁺ CD25^– T cells to CD4⁺ CD25⁺ Tregs in response to IFN-γ in vitro. (A) CD4⁺CD25^– T cells were purified from splenocytes of unprimed GKO (IFN-γ^–/–) and WT (IFN-γ^+/+) mice, respectively, and cultured in the presence and absence (medium control) of recombinant mouse IFN-γ for 24 hours. The resulting T cells (inhibitor) were examined for their ability to inhibit the proliferation of syngeneic CD4⁺CD25^– T cells (responder) induced by antibodies to CD3/CD28. Results are given as percentage of inhibition rate. (B) Aliquots of the T cell preparations described above were analyzed in parallel experiments for the expression of Foxp3 by real-time PCR. (C) CD4⁺CD25^– T cells described above were cultured with (gray contours) or without IFN-γ (open contours) in the presence or absence of anti-CD3 antibody. Intracellular expression of Foxp3 was measured in gated CD4⁺ T cells or CD4⁺CD25⁺ T cells. Indicated percentage refers to percentage of change between experimental groups with or without IFN-γ treatment. Purified CD4⁺CD25⁺ T cells (Tregs) from WT or GKO mice were stained for intracellular Foxp3 expression. Asterisks indicate that differences between groups are statistically significant; *P < 0.05.