Fig. 3

B. breve does not exhibit cytoprotective activity during T. vaginalis infection. (A) The secretions of IL-6 from HeLa cells infected with T. vaginalis and B. breve-treated T. vaginalis were determined after 24 hours of incubation. The treated cells were washed, incubated, stained with Giemsa, and monitored under a microscope: (B) upper left, HeLa cells only; upper right HeLa cells treated with B. breve for 3 hours and cultured in serum- and antibiotic-free DMEM for 12 hours; lower left, HeLa cells were co-cultured with T. vaginalis in serum- and antibiotic-free DMEM for 12 hours; lower right, HeLa cells were pretreated with B. breve in serum- and antibiotic-free DMEM for 3 hours, followed by infection with T. vaginalis under the same conditions for 12 hours. (C) The quantified chart of (B). (D) The same settings as B were applied for heat-killed B. breve (HK-Bb) instead of viable B. breve. (E) The quantified chart of (D). Statistical significance: *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001.