FIG 7 .

C. neoformans Atm1-depleted cells have decreased fitness upon coincubation with macrophage-like cell lines. (A) C. neoformans Atm1-depleted cells showed a trend toward reduced virulence in an intranasal mouse model of cryptococcosis. Cultures of strains Atm1-F (DTY967) and Gal7-Atm1-F (DTY969) were grown in SC-Gluc medium for 2 days and inoculated intranasally into two groups of 10 A/J mice with an inoculum size of 10⁵ cells per mouse. Survival data are represented in a Kaplan-Meier plot, and statistical analysis was performed with the log-rank test (P = 0.82). (B) Cultures of strains prepared as described for panel A were grown in SC-Gluc medium for 2 days, diluted to 5 × 10⁵ cells per ml in Dulbecco’s modified Eagle’s medium (DMEM), opsonized, and coincubated with the activated J774a.1 murine macrophage-like cell line at a multiplicity of infection (MOI) of 3:1. After the coincubation period, C. neoformans colonies were plated in SC-Gluc medium and representative pictures were taken at the indicated times (left panel). CFU counts were determined after 48 h or 72 h of incubation at 30°C and are presented relative to the data obtained for the Atm1-F strain (right panel). n = 3 (two-way repeated-measures ANOVA test, P = 0.03).