Figure 5.

rRFs activate endosomal TLR in human macrophages

(A) Cumulative plot of the plasma sncRNA reads in the selected regions of 18S and 28S rRNAs. The regions generating two specific rRFs, 18S-np22 and 28S-np4533, are shown. The shaded regions indicate SD from four replicates.

(B) Secondary structure of the rRFs. The targeted rRF plus 50-nt upstream and downstream region were used for prediction.

(C) After DOTAP-mediated endosomal delivery of the indicated RNAs into macrophages, culture medium was subjected to measurement of concentration of the indicated cytokines. The error bars denote the SD of three independent experiments. ∗∗p < 0.01; ∗∗∗p < 0.001.

(D) The DOTAP experiments were performed by using TLR7 KO macrophages, followed by quantification of cytokine mRNAs by RT-qPCR. Two independent experiments were performed, which are shown as separated bars, while the error bars indicate the SD of qPCR replicates.

(E and F) After DOTAP-mediated endosomal delivery of the indicated RNAs, macrophages were subjected to bacterial infection and invasion assay. Representative pictures of the plates with E. coli colonies (E) and bar graphs of the counted numbers of colonies (F) are shown. The error bars indicate the SD of three independent experiments. ∗p < 0.05; ∗∗p < 0.01.