Normal T cell activation was reported in pik3cg−/− mice during adjuvant-induced arthritis [42] and equivalent naïve CD4+ T cell activation was reported between WT and pik3cg−/− T cells induced both in vitro and in vivo using TCR-transgenic mice [38] and in a related study by Berod et al. [43]. This evidence concerns the gene CD4 and Arthritis.