At 2 days post-fertilization (dpf),Lyz:dsRed or mpx:GFPlarvae were transferred into DMSO ctrl or FK506 (1 μg/ml) containing 0.5 × E2. At 3 dpf, zebrafishlarvae were microinjected with AFeGFPconidia into the hindbrain and mortality, and fungal burden and neutrophil recruitment were assessed.C For survival analysis, lyz:dsRedlarvae were microinjected with ˜10 conidia and the effects of FK506 on the outcome from invasive aspergillosis was determined by Kaplan-Meier analysis for survival over 6 days post-infection (n = 16 per group). Immunosuppression led to a significant increase in mortality. 