Kinetics of cytokines and chemokines gene expression distinguishes Paracoccidioides brasiliensis infection from disease

The human infection with Paracoccidioides brasiliensis may result in three major outcomes: the paracoccidioidomycosis-infection (PI), the adult form (AF) and the juvenile form (JF) of the disease. The aim of this study was to compare the immunological response among these groups. The gene expression of multiple cytokines, including IL-4, IL-5, IL-6, IL-10, IFN-γ, TNF-α and TGF-β1, and chemokines, CXCL8, CXCL9 and CXCL10 was evaluated by RT-PCR in peripheral blood mononuclear cells unstimulated or following phytohemagglutinin stimulation for 3, 6, 12, 24 and 48 h. PI individuals expressed earlier and higher levels of mRNA of IFN-γ, TNF-α, CXCL9 and CXCL10 when compared to JF patients. In relation to AF patients, the PI group presented similar levels of CXCL10 and IFN-γ and higher levels of CXCL9. On the other hand, mRNA expression of Th2 cytokines (IL-4, IL-10, IL-5 and TGF-β1) was higher and earlier in JF and AF groups, when compared to PI individuals. At some time intervals it was possible to differentiate JF from AF, mainly in relation to IL-4 and TGF-β1 mRNA, expressed in higher levels in the JF patients. The distinct patterns of cytokines and chemokines expression support their important role in determining the different outcomes observed in this disease.