Fig. 1

P. acnes triggers IL-1β secretions in THP-1. Cells were treated with P. acnes at multiplicity of infection levels of 0, 10, and 20 for 24 h. A ELISA was used to determine the level of IL-1β secretion in cell supernatants after exposure to P. acnes at different multiplicities of infection. B RT-PCR analysis of IL-1β messenger RNA expression. C Protein level determined by western blot of NLRP3, pro-IL-1β, and pro-caspase-1 in cell extracts (CE) and IL-1β and caspase-1 (p10) in supernatants (SN). The control was THP-1 cultured in RPMI-1640 without FBS. n = 5; *p < 0.05; **p < 0.01; ***p < 0.001