ABSTRACT
Objective@#To determine the impact and mechanism of HIV derived microRNA99 (miRNA99) on macrophages pyroptosis.@*Methods@#THP-1 cells were stimulated by phorbol ester (PMA) and then were cultured and differentiated into sidewall attached macrophages; the morphology and phenotype of CD11b were measured by microscopy and flow cytometry. TLR8 RNAi plasmid was transfected to macrophages and were detected by confocal fluorescence microscopy. The levels of IL-18 and IL-1β released by macrophages were measured by ELISA. Western blot(WB) was employed to examine TLR8 and cleaved caspase-1 protein expression in macrophages.@*Results@#THP-1 cells that were challenged with PMA (100 ng/ml) for 24 h became smooth and adherent. In addition, the expression of CD11b in macrophages was up to 99%. TLR8 protein expression in macrophages transfected with TLR8 plasmids was significantly lower than that in macrophages transfected with control plasmids. Levels of IL-18 and IL-1β secreted by macrophages were elevated in LPS+ ATP group, miRNA99 group and control plasmid group, but not in control group and TLR8 RNAi plasmid group. Cleaved caspase-1 protein from macrophages of miRNA99 experimental group/ LPS+ ATP group and control plasmid group was significantly higher than that of control group and TLR8 RNAi plasmid group.@*Conclusions@#The present study demonstrates that HIV-derived miRNA99 could induce pyroptosis of macrophages via TLR8-dependent pathway.