Downregulation of TLR7 and TNFA by miR-17-92. Splenic stromal cells were transfected with pGFP-C-lenti-miR-17, pGFP-C-lenti-miR-19a, pGFP-C-shlenti-antimiR-17, or pGFP-C-shlenti-antimiR-19 vectors and stimulated with medium or IFN-α (1000 U/ml) for 24 hours. TLR7 and TNFA expression were then measured by RT-PCR. (A) Quantification of miR-17 and miR-19a confirmed increased expression in transfected miR-17 and miR-19a cell lines and decreased expression in transfected as-miR-17 and as-miR-19a cells compared with control cells. (B) Increased miR-17 and (C) miR-19a levels inhibited IFN-α–mediated induction of TLR7 (B-C; left panels) and TNFA (B-C; right panels) mRNA, whereas the antisense inhibitors had opposite effects. The average and SD of the results of 3 independent measurements are shown. (D) TNF-α proteins in 24-hour culture supernatants were measured by enzyme-linked immunosorbent assay. *P < .05, **P < .01, ***P < .001.