Effect of serum on cryptococcal cell growth.

<p>H99 cell suspensions were inoculated in Sabouraud (A), Sabouraud supplemented with 5% serum (B) or TCM (C). The cells were incubated overnight at 37°C in 5% CO₂. Then, the cells were suspended in India Ink and pictures of the cell body size were taken. The scale in A applies to all the pictures. (D) Effect of purified serum lipids on cell growth. The cells (initial density 10⁴ cells/mL) were grown in TCM medium in which the serum was replaced by different dilutions (40, 100 and 200) of the lipid extract. As controls, the same media was supplemented with PBS. Cultures in TCM are also included for reference. Cell body size was determined after 24 hours at 37° C with CO₂ and shaking. The asterisks indicate significant differences compared to Sabouraud control. (E) Effect of phosphatydilcholine on titan-like cell formation. Cells were incubated as in (A), but serum was replaced by 0.1 mM of phosphatidylcholine (PC). A parallel control with the same concentration of ethanol was carried out in parallel. The graph shows the cell body size.