The proportion of naïve T cells increased in IFN-γ/IL-17 double knockout mice compared to that of IFN-γ KO mice.

<p>Spleen, draining lymph nodes and mesenteric lymph node were removed at 5^th week after 1^st immunization, and prepared for single cell suspension. They were stained with PerCP - anti CD4 ab, APC - anti CD44 ab, and FITC - anti CD62L ab for flowcytometry. (a) Data represents one of three experiments. (b) CD4⁺CD44^highCD62L^low (memoryCD4⁺T cells) T cell population was decreased in CIA (IFN-γIL-17 DKO) group while CD4⁺CD44^lowCD62L^high (naïve CD4⁺ T cells) population was increased. (c) IL-2, IL-15 and IL-21 were strongly expressed in the joint synovium of CIA (IFN-γ KO). Original magnification, 200x. Mann-Whitney U test used (b). Values are presented as the mean ± standard deviation of four independent experiments. *, p<0.05, **, p<0.005 ***, p<0.001.