TABLE 4.

Effect of temperature on M. tuberculosis uptake by human macrophages

StrainTime of exposure (h)aUptake (% of initial inoculum) of M. tuberculosis at:
23°C30°C37°C
H37Rv26.1 ± 210 ± 316.8 ± 4b
47.2 ± 412 ± 318 ± 5b
Erdman27.4 ± 0.411.9 ± 419.7 ± 5b
47.9 ± 314 ± 324 ± 6b
  • a Bacteria were exposed to different temperatures for 2 or 4 h, washed at 4°C, and used to infect macrophages in the presence of 10% heat-inactivated autologous serum. Results are means ± standard deviations.

  • b P < 0.05 compared with uptake of bacteria exposed to 23 or 30°C.