FIG 3.

Synergistic effect of C. pneumoniae with CNTs on IL-1β secretion from macrophages does not require bacterial growth or de novo bacterial protein synthesis. (A) Chlamydial growth in macrophages treated with or without CNTs. The C. pneumoniae-stimulated THP-1 cells were cultured during 3 days in the presence or absence of CNTs. The amounts of chlamydial (16S rRNA genes [rDNA]) and host cell DNA (GAPDH gene) were monitored by qPCR, and the data (averages ± standard deviations) show a ratio of chlamydial 16S rRNA genes to the GAPDH gene. NS, not significant; Cpn; C. pneumoniae. (B) Effect of de novo protein synthesis by C. pneumoniae on IL-1β secretion from macrophages. The C. pneumoniae-stimulated THP-1 cells treated with CNTs were cultured for 24 h in the presence or absence of 50 μg/ml chloramphenicol (with ethyl acohol [EtOH] as the solvent control), and IL-1β secretion was detected by Western blotting. CP, chloramphenicol; sup, desalinized culture supernatants of THP-1 cells; cell, the remaining cells; Cpn, C. pneumoniae; CNT, carbon nanotube.