Specific IgG against three recombinant proteins of A. fumigatus [88, 18 kDa, and catalase] were significantly higher in STAT3-deficient patients with ongoing aspergillosis compared to those without aspergillosis (representative data shown for A. fumigatus 88 KDa proteins in Figure 1C and Table 2; p < 0.01). Here, STAT3 is linked to aspergillosis.