Suppressed expression of miR-378 targeting gzmb in N cells is required to control dengue virus infection

• Published in: 中国免疫学杂志：英文版 2016, Vol.13 (5), p.700-708
• Main Author: Shuyan Liu Lingming Chen Ying Zeng Lulu Si Xiaolan Guo Junmei Zhou Danyun Fang Gucheng Zeng Lifang Jiang
• Format: Article
• Language: English
• Subjects: NK细胞; 控制; 生物学基础; 病毒复制; 病毒感染; 病理机制; 登革热; 细胞毒性
• ISSN: 1672-7681; 2042-0226

Dengue virus （DENV） remains a major public health threat because no vaccine or drugs are available for the prevention and treatment of DENV infection, and the immunopathogenesis mechanisms of DENV infection are not fully understood. Cytotoxic molecules, such as granzyme B （GrzB）, may be necessary to control viral infections. However, the exact role of GrzB during DENV infection and the mechanisms regulating GrzB expression during DENV infection are not clear. This study found that miR-27a~, miR-3Oe, and miR-378 were down-regulated in DENV-infected patients, and DENV infection in humans induced a significant up-regulation of GrzB in natural killer （NK） cells and CD8＋ T cells. Further investigation indicated that NK cells, but not CD8＋ T cells, were the major sources of GrzB, and miR-378, but not miR-27a~ or miR-3Oe, suppressed GrzB expression in NK cells. Notably, we found that overexpression of miR-378 using a miR-378 agomir in DENV-infected mice inhibited GrzB expression and promoted DENV replication. These results suggest the critical importance of miR-378 in the regulation of GrzB expression and a protective role for GrzB in controlling DENV replication in vivo. Therefore, this study provides a new insight into the immunopathogenesis mechanism of DENV infection and a biological basis for the development of new therapeutic strategies to control DENV infection.