Number and ratio of T-helpers and disease severity. (A-B) The absolute numbers of Th2 and Th17 cells were significantly higher in pretreatment patients with severe (n = 15) and very severe (n = 12) AA (SAA) than in healthy donors. (C) The ratios of all T-helpers to Tregs were correlated with disease severity, and as shown, all ratios were significantly higher in patients with pretreatment severe and very severe disease than in those with nonsevere AA (NSAA).