We first analyzed the mRNA expression of cytokines (IL-4, IL-9, L-10, IL-17, IL-22, IFN-γ, TNF-α, TGF-β) and transcription factors (PU.1, GATA-3, RORγt, AHR, T-Bet, FoxP3) in PBMCs obtained from Chagas disease patients who exhibited the indeterminate, cardiac, cardiodigestive and digestive clinical forms of the disease. Here, IL9 is linked to Chagas disease.