Fig 1: The effects of IL-1 and IL-1RA on osteoclastogenesis induced by the culture supernatant of NEM-F cells and on the expression of NFATc1 in these cultures. (a) Evaluation of the effects of IL-1, IL-1RA, and an antagonistic antibody for IL-1R1 on osteoclastogenesis induced by the culture supernatant of NEM-F cells. Representative views of TRAP staining after 5 days of culture. (b) The number of osteoclasts induced by the culture supernatant of NEM-F cells with or without treatment with IL-1, IL-1RA, or an antagonistic antibody for IL-1R1. ** p < 0.01 (one-way ANOVA with the Dunnett’s method). (c) Quantitative PCR analysis of the expression of NFATc1 in OPCs cultured with culture supernatant of NEM-F cells with or without supplementation of IL-1RA or IL-1a relative to the expression in OPCs cultured with the growth medium with or without supplementation of RANKL. ** p < 0.01, ns: not significant (one-way ANOVA with the Tukey–Kramer method). (d) Evaluation of the effects of IL-1 and IL-1RA on the osteolytic function of induced osteoclasts by the coculture of NEM-F cells and OPCs using a pit formation assay. Representative views of formatted pits after 6 days of culture. (e) The number of pits formed by osteoclasts induced by the coculture of NEM-F cells and OPCs with or without supplementation of IL-1RA or IL-1a. ** p < 0.01 (one-way ANOVA with the Dunnett’s method).