C3 and systemic lupus erythematosus: The percentage of peripheral Vδ2 T cells in SLE patients negatively correlated with disease activity, as determined by the SLEDAI score (r = −0.656, p = 0.008, Fig. 3A), but not with the titer of anti-dsDNA autoantibodies or the serum C3 levels (p > 0.05, Fig. 3B,C).