Fig 1.
Wolbachia titers return to control levels 8 months after rifampicin treatment.
Female and male Brugia pahangi from jirds treated with rifampicin were analyzed by qPCR to determine Wolbachia titers at each timepoint. Mean percent reductions of Wolbachia wsp/gst ratios from female (A) and male (B) adult worms are shown at 1-week, 6-weeks, 17-weeks and 8-months post-first dose. Data shown are medians and the boxes are the 25th and 75th percentiles with ***P<0.001 and *P<0.05. n = 2–9 jirds per treatment group per timepoint. Additional information is shown in S1 Table.
Fig 2.
Rifampicin decreases mf shedding from female worms up to 6 weeks, followed by a return to normal by 17 weeks.
The number of mf shed overnight by adult female worms that were recovered 1 week, 6 weeks, 17 weeks and 8-months post-first dose is shown for each timepoint. Mf shed overnight at the 1- and 6-week timepoint were significantly reduced (*P<0.05 and ****P<0.0001, respectively). Data are shown as median ± 95% CI. n = 10–26 female worms from n = 2–9 jirds per treatment group per timepoint.
Fig 3.
Rifampicin treatment leads to impaired embryogenesis by the 6-week timepoint but normal developmental stages return by 17 weeks.
Embryonic stages found within the ovaries and uteri from female worms from the vehicle and treated groups were counted 1 week, 6 weeks, 17 weeks and 8 months post-first dose. There was a significant decrease in the frequency of healthy embryos across all developmental stages of embryogenesis at the 6-week timepoint (****P<0.0001). Percentages of degenerated embryos (gray) were also determined for each timepoint. Data are presented as mean ± SEM. n = 6–9 female worms from n = 2–9 jirds per treatment group per timepoint.
Fig 4.
Rebound of Wolbachia at later timepoints may be driven by clusters.
Ovaries were removed from individual female worms, fixed and stained for host nuclei (magenta) and Wolbachia (red). (A) Wolbachia are depleted at 1- and 6-weeks post-treatment but begin to rebound by 17 weeks. (B) Clusters of Wolbachia are seen in ovaries from vehicle and rifampicin worms; actin (green) stained with phalloidin; Wolbachia (red) stained with propidium iodide and host nuclei (magenta) stained with DAPI. (C) Wolbachia were quantified by counting number of puncta within the clusters (left) and in the periphery of the clusters (right). (D) Clusters were analyzed from worms collected at 6 weeks (n = 36–46), 17 weeks (n = 6–8) and 8 months (n = 34–52). Vehicle control worms in yellow and worms from rifampicin treated groups in red. Peripheral Wolbachia were reduced in females recovered from rifampicin treated jirds at the 6-week timepoint only (P = 0.05). Data are presented as median ± 95% CI.