FIG 3.
Infection and replication of B. abortus within THP-1 monocytes. After infection at different MOI in the presence or not of cortisol (1 × 10−6 M), DHEA (1 × 10−8 M), or cortisol plus DHEA (1 × 10−6 M and 1 × 10−8 M, respectively), cells were incubated with antibiotics to kill extracellular bacteria. Cell lysates obtained at 24 h p.i. were plated onto agar to determine intracellular CFU (A). At 2, 6, 24, and 48 h postinfection, THP-1 cells treated or not with cortisol were plated on agar to determine intracellular CFU (B). Data are given as means ± SEM from at least 4 individual experiments. Significance of results for treated versus untreated cells: **, P < 0.01; ***, P < 0.001.