CD4 and systemic lupus erythematosus: (iv) IL-6: Significantly higher IL-6 levels of 1,150 ± 30 pg/ml at 3 days and 4,747 ± 67 pg/ml IL-6 at 7 days were secreted by SLE-PBMCs when compared to CD4+CD25+CD127low UCB-Tregs alone levels of 0 pg/ml for both the corresponding time points (p < 0.0001).