IL4 and ataxia telangiectasia: The plasma concentrations of IL-21, IL-4, and IL-17A were significantly elevated in BT-GD patients, the levels of these cytokines from some GD patients were significantly reduced in the AT-GD group compared to the BT-GD group, and there was no significant difference about the IL-4 and IL-17A cytokines between the AT-GD and HC groups except the plasma IL-21 level (Figures 4(a)–4(c)).