MicroRNA-155 in exosomes secreted from helicobacter pylori infection macrophages immunomodulates inflammatory response.

Exosomes containing microRNA-155 act as molecule carriers during immune cell-cell communication and play an important role in the inflammatory response of infection macrophages. Previous reports have found that miR-155 was over-expressed in infection macrophages, but the significance of which is still unknown. In this study, we analyzed the impact of miR-155 loaded in exosomes derived from macrophages to the inflammatory response of infection macrophages and possible mechanisms. We found that miR-155 promoted the expression of inflammatory cytokines including TNF-a, IL-6, IL-23, but also increased the expression of CD40, CD63, CD81, and MCH-I. Meanwhile, inflammatory signal pathways proteins, such as MyD88, NF-κB in infection macrophages were down-regulated due to the over-expression of miR-155. Experiments or revealed that miR-155 promoted macrophages to inhibit or kill by regulating the inflammatory response of cells to prevent the gastritis caused by infection. These findings contribute to the understanding of miR-155 contained in exosomes in inflammatory responses of infection macrophages.