Fig. 2.

Caspofungin impairs early hyphal proliferation in neutropenic but not corticosteroid-immunosuppressed mice with invasive pulmonary mucormycosis. Select experiments were repeated with groups of 5 animals to compare lung histology results at 72 h by comparing the lungs of neutropenic (a to c) and corticosteroid-immunosuppressed (e to g) mice. Lungs were excised and fixed in 10% (vol/vol) formaldehyde and embedded in paraffin wax before being subjected to staining with Grocott's methenamine silver nitrate (a to c, e, and f) or hematoxylin and eosin (g). Photomicrographs were acquired at a magnification of ×200 (scale bar, 25 μm) with 3 separate areas of infiltration per mouse, and hyphal length was calculated for all discernible hyphal elements in the lung field (average, 35 hyphae per field) by the use of calibrated computer image analysis software (Macnification version 1.5; Orbicule BVBA, Heverless, Belgium). Mean hyphal lengths for mice in the neutropenic (d) and corticosteroid-immunosuppressed (h) treatment groups at 72 h were compared using the Kruskal-Wallis test.