Inhibition of miR-93 promotes interferon effector signaling to suppress influenza A infection by upregulating JAK1
INTERNATIONAL IMMUNOPHARMACOLOGY
Authors: Guo, Meng; Li, Fangbing; Ji, Junsong; Liu, Yanfang; Liu, Fang; Zhao, Yuanyu; Li, Junhui; Han, Shu; Wang, Quanxing; Ding, Guoshan
Abstract
Type I interferons play a critical role in host defense against influenza virus infection. Interferon cascade induces the expression of interferon-stimulated genes then subsequently promotes antiviral immune responses. The microRNAs are important regulators of innate immunity, but microRNAs-mediated regulation of interferon cascade during influenza infection remains to be fully identified. Here we found influenza A virus (IAV) infection significantly inhibited miR-93 expression in alveolar epithelial type II cells through RIG-I/JNK pathway. IAV-induced downregulation of miR-93 was found to upregulate JAK1, the target of miR-93, and then feedback promote antiviral innate response by facilitating IFN effector signaling. Importantly, in vivo administration of miR-93 antagomiR markedly suppressed IAV infection, protecting mice form IAVs-associated death. Hence, the inducible downregulation of miR-93 feedback suppress IAV infection by strengthening IFN-JAK-STAT pathway via JAK1 upregulation, and in vivo inhibition of miR-93 bears considerable therapeutic potential for suppressing IAV infection.
Dual and Triple Infections With Influenza A and B Viruses: A Case-Control Study in Southern Brazil
JOURNAL OF INFECTIOUS DISEASES
Authors: Gregianini, Tatiana Schaffer; Santos Varella, Ivana R.; Fisch, Patricia; Martins, Leticia Garay; Veiga, Ana B. G.
Abstract
Influenza surveillance is important for disease control and should consider possible coinfection with different viruses, which can be associated with disease severity. This study analyzed 34 459 patients with respiratory infection from 2009 to 2018, of whom 8011 were positive for influenza A virus (IAV) or influenza B virus (IBV). We found 18 cases of dual influenza virus infection, including coinfection with 2009 pandemic influenza A(H1N1) virus (A[H1N1]pdm09) and influenza A(H3N2) virus (1 case), A(H1N1) pdm09 and IBV (6 cases), A(H3N2) and IBV (8 cases), and nonsubtyped IAV and IBV (3 cases); and 1 case of triple infection with A(H3N2), A(H1N1)pdm09, and IBV. Compared with 76 monoinfected patients, coinfection was significantly associated with cardiopathy and death. Besides demographic characteristics and clinical symptoms, we assessed vaccination status, antiviral treatment, timeliness of antiviral use, hospitalization, and intensive care unit admission, but no significant differences were found between coinfected and monoinfected cases. Our findings indicate that influenza virus coinfection occurs more often than previously reported and that it can lead to a worse disease outcome.