Impact ofL.reuteri CCS on osteoclast differentiation at different time points. RAW264.7 cells were plated and osteoclast differentiation was induced with the addition of 100 ng/mL RANKL. L. reuteri CCS was added normally when the media was replenished (days 1, 3, and 5) or just once on day 1, 3, or 5. After 7 days, the number of giant multinucleated (≥ 3 nuclei) cells staining positive for TRAP were quantified. Treatment by L. reuteri CCS on day 1 was sufficient to suppress osteoclastogenesis. Three biological replicates are depicted with associated standard error of mean, *p < 0.05 compared to untreated and MEM-α (vehicle control) conditions as determined by one-way ANOVA.