FIG. 7.

Survival of A/J mice infected with either 10⁷ C. neoformans cells grown with live D. discoideum (−▪−) (n = 15), 10⁷ C. neoformans cells grown with killed D. discoideum (−○−) (n = 15), 10⁷ C. neoformans cells (-▴-) (n = 15), or 10⁷ live D. discoideum cells (-×-) (n = 5). The graph shows that C. neoformans 24067 primed by growth with live D. discoideum is more lethal than C. neoformans grown either alone or with killed D. discoideum (P ≤ 0.005 for both). Also, D. discoideum alone was not pathogenic. There were no significant differences in the survival of mice infected with C. neoformans alone and C. neoformans grown with killed D. discoideum (P = 0.974). This experiment was performed twice with similar results.