In the early stage after RB6-8C5 treatment, although immunocompetent, macrophages were not sufficient to avoid conidial germination. (A): Multifocal small inflammatory infiltrates randomly scattered in the pulmonary parenchyma. (B): Small clusters of fungi were observed in the inflammatory infiltrates. (C): Inflammatory infiltrates were located in alveolar spaces or interalveolar interstitial tissue. They contained mononucleated cells (mainly macrophages but also rare lymphocytes and plasma cells). (D, E, F): Early germinating conidia were observed in the inflammatory infiltrates either free or in the cytoplasm of alveolar macrophages (arrowheads). Note that the conidia and hyphae were less mature than under cortisone acetate treatment (Figure. 6). A, C: HE staining; B, D, E, F: GMS staining.