FIG. 8.

Effect of capsule age on capsule sensitivity to gamma irradiation. (A) After incubation of cryptococcal cells in capsule-inducing conditions overnight or for 7 or 14 days, cells were gamma irradiated for 0, 20, or 40 min, and the population was observed by India ink staining. (B) Decrease in capsule size of cells, based on hematocrit cell packing, as a result of gamma irradiation for overnight (⧫), 7-day (▪), or 14-day (▴) cultures. The calculations were based on the percent volume of the 0-min (untreated) sample. Average capsule volumes were measured by hematocrit cell packing.