Second, further studies should investigate cell-contact Treg suppression and functional cytokine production (IL-10, TGF-β, and IL17) if more blood samples are available, because isolated lymphocytes of CGD patients have been shown to secrete higher levels of IL17A in vitro in co-cultures with CD3CD28 (58). This evidence concerns the gene TGFB1 and chronic granulomatous disease.