Figure 6.

Olp1 regulates fungal virulence in a mouse systematic infection model. (A) Female C57 BL/6 mice were infected intranasally with 10⁵ cells of the wild-type H99, the olp1Δ mutants (TBL337), olp1Δ::OLP1 complementation strains (TBL349), and OLP1 overexpression strain OLP1^OE (TBL353). Both the olp1Δ mutant and OLP1^OE strain are less virulent than the wild-type H99 strain. ns, not significant; ****, p ≤ 0.0001 (determined by log-rank [Mantel–Cox] test). (B) Organs from five mice infected with H99, the olp1Δ mutants, olp1Δ::OLP1 complemented strains, and OLP1^OE strain were dissected for colony-forming unit (CFU) counting at the end time point of infection. The data shown are the mean ± SD for values from five animals. *, p ≤ 0.05; **, p ≤ 0.01; ****, p ≤ 0.0001 (determined by Mann–Whitney test). (C) Hematoxylin and eosin (H&E)-stained slides were prepared from cross-sections of infected organs at the endpoint of the experiment and visualized by light microscopy. The cryptococcal cells are indicated by arrows. Brain: Bar = 20 μm, Lung: Bar = 20 μm, Spleen: Bar = 20 μm.