The overall results of this study, once integrated, have allowed to differentiate five chronological stages occurring during the course of experimental PCM induced by inhalation of infective P.b conidia, as follows: In the first stage (2 hours p.i.), a mild septal neutrophilic and macrophagic infiltration accompanied by an intense “cytokine burst” was observed in lung tissues as shown by a significant increase of IL-1α, IL-1β, IL-4, IL-5, IL-6, IL-10, IL-12p70, IL-13, IL-17, Eotaxin, G-CSF, MCP1, MIP1α, GM-CSF, IFN-γ, MIP1β and TNFα (patterns 1 and 2). This evidence concerns the gene IL4 and paracoccidioidomycosis.