HIV-1 infection modulates IL-24 expression which contributes to cell apoptosis in vitro

IL-20 Cytokines Are Involved in Epithelial Lesions Associated with Virus-Induced COPD Exacerbation in Mice

(1) Background: viral infections are a frequent cause of chronic obstructive pulmonary disease (COPD) exacerbations, which are responsible for disease progression and mortality. Previous reports showed that IL-20 cytokines facilitate bacterial lung infection, but their production and their role in COPD and viral infection has not yet been investigated. (2) Methods: C57BL/6 WT and IL-20 Rb KO mice were chronically exposed to air or cigarette smoke (CS) to mimic COPD. Cytokine production, antiviral response, inflammation and tissue damages were analyzed after PVM infection. (3) Results: CS exposure was associated with an increase in viral burden and antiviral response. PVM infection in CS mice enhanced IFN-γ, inflammation and tissue damage compared to Air mice. PVM infection and CS exposure induced, in an additive manner, IL-20 cytokines expression and the deletion of IL-20 Rb subunit decreased the expression of interferon-stimulated genes and the production of IFN-λ2/3, without an impact on PVM replication. Epithelial cell damages and inflammation were also reduced in IL-20 Rb^-/- mice, and this was associated with reduced lung permeability and the maintenance of intercellular junctions. (4) Conclusions: PVM infection and CS exposure additively upregulates the IL-20 pathway, leading to the promotion of epithelial damages. Our data in our model of viral exacerbation of COPD identify IL-20 cytokine as a potential therapeutic target.

Host-virus interaction and viral evasion

With each infectious pandemic or outbreak, the medical community feels the need to revisit basic concepts of immunology to understand and overcome the difficult times brought about by these infections. Regarding viruses, they have historically been responsible for many deaths, and such a peculiarity occurs because they are known to be obligate intracellular parasites that depend upon the host's cell machinery for their replication. Successful infection with the production of essential viral components requires constant viral evolution as a strategy to manipulate the cellular environment, including host internal factors, the host's nonspecific and adaptive immune responses to viruses, the metabolic and energetic state of the infected cell, and changes in the intracellular redox environment during the viral infection cycle. Based on this knowledge, it is fundamental to develop new therapeutic strategies for controlling viral dissemination, by means of antiviral therapies, vaccines, or antioxidants, or by targeting the inhibition or activation of cell signaling pathways or metabolic pathways that are altered during infection. The rapid recovery of altered cellular homeostasis during viral infection is still a major challenge. Here, we review the strategies by which viruses evade the host's immune response and potential tools used to develop more specific antiviral therapies to cure, control, or prevent viral diseases.

IP-10 and CXCR3 signaling inhibit Zika virus replication in human prostate cells

Our previous studies have shown that Zika virus (ZIKV) replicates in human prostate cells, suggesting that the prostate may serve as a long-term reservoir for virus transmission. Here, we demonstrated that the innate immune responses generated to three distinct ZIKV strains (all isolated from human serum) were significantly different and dependent on their passage history (in mosquito, monkey, or human cells). In addition, some of these phenotypic differences were reduced by a single additional cell culture passage, suggesting that viruses that have been passaged more than 3 times from the patient sample will no longer reflect natural phenotypes. Two of the ZIKV strains analyzed induced high levels of the IP-10 chemokine and IFNγ in human prostate epithelial and stromal mesenchymal stem cells. To further understand the importance of these innate responses on ZIKV replication, we measured the effects of IP-10 and its downstream receptor, CXCR3, on RNA and virus production in prostate cells. Treatment with IP-10, CXCR3 agonist, or CXCR3 antagonist significantly altered ZIKV viral gene expression, depending on their passage in cells of relevant hosts (mosquito or human). We detected differences in gene expression of two primary CXCR3 isoforms (CXCR3-A and CXCR3-B) on the two cell types, possibly explaining differences in viral output. Lastly, we examined the effects of IP-10, agonist, or antagonist on cell death and proliferation under physiologically relevant infection rates, and detected no significant differences. Although we did not measure protein expression directly, our results indicate that CXCR3 signaling may be a target for therapeutics, to ultimately stop sexual transmission of this virus.