FIGURE 4.

Histology reveals reduced fungal colonization by avirulent rpdA^xylP in the absence of xylose. Lungs were extracted 2 days post intranasal infection of cortisone-acetate immunocompromised mice. (A) Mouse lung fungal burden is reduced in mice infected with rpdA^xylP−xylose (xyl) compared to wild type (P = 0.0094) and rpdA^xylP +xylose (P = 0.0292). (B) Hyphal lesions from rpdA^xylP –xylose contain significantly less fungal hyphae (P < 0.0001) than those from rpdA^xylP +xylose and wild type. The extend of fungal growth was measured by manually tracing the combined length of hyphae in each lesion (n = 10) using ImageJ software. (C) Representative lung sections of infected mice. Staining, performed with gomori methenamine silver (GMS), stains fungi black.