Evasion of innate and adaptive immune responses by influenza A virus

Abstract Porcine reproductive and respiratory syndrome virus (PRRSV) infection is the most important viral disease causing severe economic losses in the swine industry. However, mechanisms underlying gene expression control in immunity-responsible tissues at different time points during PRRSV infection are poorly understood. We constructed an integrated gene co-expression network and identified tissue- and time-dependent biological mechanisms of PRRSV infection through bioinformatics analysis using three tissues (lungs, bronchial lymph nodes [BLNs], and tonsils) via RNA-Seq. Three groups with specific expression patterns (i.e., the 3-dpi, lung, and BLN groups) were discovered. The 3 dpi-specific group showed antiviral and innate-immune signalling similar to the case for influenza A infection. Moreover, we observed adaptive immune responses in the lung-specific group based on various cytokines, while the BLN-specific group showed down-regulated AMPK signalling related to viral replication. Our study may provide comprehensive insights into PRRSV infection, as well as useful information for vaccine development.

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Evasion of Influenza A Viruses from Innate and Adaptive Immune Responses

Viruses ◽

10.3390/v4091438 ◽

2012 ◽

Vol 4 (9) ◽

pp. 1438-1476 ◽

Cited By ~ 101

Author(s):

Carolien E. van de Sandt ◽

Joost H. C. M. Kreijtz ◽

Guus F. Rimmelzwaan

Keyword(s):

Immune Responses ◽

Influenza A ◽

Influenza A Viruses ◽

Adaptive Immune Responses ◽

Adaptive Immune

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Disruption of nasal bacteria enhances protective immune responses to influenza A virus and SARS-CoV-2 infection in mice

10.1101/2020.12.25.424300 ◽

2020 ◽

Author(s):

Minami Nagai ◽

Miyu Moriyama ◽

Takeshi Ichinohe

Keyword(s):

Influenza Virus ◽

Immune Responses ◽

Influenza A ◽

Critical Role ◽

Influenza Virus Infection ◽

Oral Bacteria ◽

Antibody Responses ◽

Adaptive Immune Responses ◽

Adjuvant Activity ◽

Adaptive Immune

AbstractGut microbiota plays a critical role in the induction of adaptive immune responses to influenza virus infection. However, the role of nasal bacteria in the induction of the virus-specific adaptive immunity is less clear. Here we demonstrate that while intranasal administration of influenza virus hemagglutinin vaccine alone was insufficient to induce the vaccine-specific antibody responses, disruption of nasal bacteria by lysozyme or addition of culturable oral bacteria from a healthy human volunteer rescued inability of the nasal bacteria to generate antibody responses to intranasally administered the split-virus vaccine. Myd88-depdnent signaling in the hematopoietic compartment was required for adjuvant activity of intranasally administered oral bacteria. In addition, we found that the oral bacteria-combined intranasal vaccine induced protective antibody response to influenza virus and SARS-CoV-2 infection. Our findings here have identified a previously unappreciated role for nasal bacteria in the induction of the virus-specific adaptive immune responses.

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The fate of influenza A virus after infection of human macrophages and dendritic cells

Journal of General Virology ◽

10.1099/vir.0.045021-0 ◽

2012 ◽

Vol 93 (11) ◽

pp. 2315-2325 ◽

Cited By ~ 39

Author(s):

Kirsty R. Short ◽

Andrew G. Brooks ◽

Patrick C. Reading ◽

Sarah L. Londrigan

Keyword(s):

Dendritic Cells ◽

Immune Responses ◽

Influenza A Virus ◽

Immune Cells ◽

Influenza A ◽

Inflammatory Responses ◽

Critical Role ◽

Virus Release ◽

Adaptive Immune ◽

Human Immune

Airway macrophages (MΦ) and dendritic cells (DC) are important components of the innate host defence. Historically, these immune cells have been considered to play a critical role in controlling the severity of influenza A virus (IAV) infection by limiting virus release, initiating local inflammatory responses and by priming subsequent adaptive immune responses. However, some IAV strains have been reported to replicate productively in human immune cells. Potential amplification and dissemination of IAV from immune cells may therefore be an important virulence determinant. Herein, we will review findings in relation to the fate of IAV following infection of MΦ and DC. Insights regarding the consequences and outcomes of IAV infection of airway MΦ and DC are discussed in order to gain a better understanding of the pathogenesis of influenza virus.

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Benefits and Perils of Necroptosis in Influenza Virus Infection

Journal of Virology ◽

10.1128/jvi.01101-19 ◽

2020 ◽

Vol 94 (9) ◽

Cited By ~ 2

Author(s):

Siddharth Balachandran ◽

Glenn F. Rall

Keyword(s):

Cell Death ◽

Influenza Virus ◽

Immune Responses ◽

Influenza A ◽

Influenza Virus Infection ◽

Cell Types ◽

Influenza A Viruses ◽

Adaptive Immune Responses ◽

Adaptive Immune ◽

Infected Cells

ABSTRACT Influenza A viruses (IAV) are lytic viruses that have recently been found to activate necroptosis in many of the cell types they infect. Necroptotic cell death is potently immunogenic and limits IAV spread by directly eliminating infected cells and by mobilizing both innate and adaptive immune responses. The benefits of necroptosis to the host, however, may sometimes be outweighed by the potentially deleterious hyperinflammatory consequences of activating this death modality in pulmonary and other tissues.

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