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Significance Interferon (IFN)-mediated antiviral responses serve as the first line of the host innate immune defense against viral infection. Here we identify a previously uncharacterized protein designated phospholipase A2 inhibitor and LY6/PLAUR domain-containing protein (PINLYP), which is essential for embryonic development and plays an important role in type I IFN against pathogen infection. PINLYP deficiency impairs type I IFN production and dampens in vivo host defense against DNA and RNA virus infection. We unravel a unique actor in the type I IFN innate immunity and a potential target for the antiviral therapies., Type I interferons (IFNs) are the first frontline of the host innate immune response against invading pathogens. Herein, we characterized an unknown protein encoded by phospholipase A2 inhibitor and LY6/PLAUR domain-containing (PINLYP) gene that interacted with TBK1 and induced type I IFN in a TBK1- and IRF3-dependent manner. Loss of PINLYP impaired the activation of IRF3 and production of IFN-β induced by DNA virus, RNA virus, and various Toll-like receptor ligands in multiple cell types. Because PINLYP deficiency in mice engendered an early embryonic lethality in mice, we generated a conditional mouse in which PINLYP was depleted in dendritic cells. Mice lacking PINLYP in dendritic cells were defective in type I IFN induction and more susceptible to lethal virus infection. Thus, PINLYP is a positive regulator of type I IFN innate immunity and important for effective host defense against viral infection.

Gammaherpesviruses have evolved various strategies to take advantage of host cellular factors or signaling pathways to establish a lifelong latent infection. Like the human gammaherpesvirus Epstein-Barr virus, murine gammaherpesvirus 68 (MHV68) establishes and maintains latency in the memory B cells during infection of laboratory mice. We have previously shown that MHV68 can immortalize fetal liver-derived B cells that induce lymphomas when injected into immunodeficient mice. Here we identify interleukin 16 (IL16) as a most abundantly expressed cytokine in MHV68-immortalized B cells and show that MHV68 infection elevates IL16 expression. IL16 is not important for MHV68 lytic infection but plays a critical role in MHV68 reactivation from latency. IL16 deficiency increases MHV68 lytic gene expression in MHV68-immortalized B cells and enhances reactivation from splenic latency. Correlatively, IL16 deficiency increases the frequency of MHV68-infected plasma cells that can be attributed to enhanced MHV68 reactivation. Furthermore, similar to TPA-mediated lytic replication of Kaposi's sarcoma-associated herpesvirus, IL16 deficiency markedly induces Tyr705 STAT3 de-phosphorylation and elevates p21 expression, which can be counteracted by the tyrosine phosphatase inhibitor orthovanadate. Importantly, orthovanadate strongly blocks MHV68 lytic gene expression mediated by IL16 deficiency. These data demonstrate that virus-induced IL16 does not directly participate in MHV68 lytic replication, but rather inhibits virus reactivation to facilitate latent infection, in part through the STAT3-p21 axis., Author summary Gammaherpesviruses establish life-long infection in B cells through the regulation of virus-host interaction. Following initial lytic infection, viruses infect B cells and take advantage of host cellular factors and signaling pathways to manipulate B cell responses, ultimately establish latency in B cells, which can be reactivated to induce lytic replication in some circumstances. Here we use a mouse model of gammaherpesvirus infection and show that IL16, one unique cytokine regulating CD4+ T cell function, is highly abundant in gammaherpesvirus-associated lymphoma cells and can be induced by gammaherpesvirus infection. In the absence of IL16, virus reactivation from B cells is markedly enhanced and the frequency of virus-infected plasma cells that account for virus reactivation is also significantly increased. These results illustrate how gammaherpesvirus takes advantage of host cellular factor to regulate its life-long latent infection.

Human exposure risks to airborne pollutants, bacteria and viruses in confined spaces have attracted tremendous attention. It is a challenge to degrade these harmful materials over a single device by electrical method other than conventional thermal method. We fabricated an air cleaning device based on a conductive Ag-Co3O4 coating with Ag nanoparticles on a glass fibre cloth (GFC). The device possessed good flexibility and high permeability of the GFC. Powered by low-voltages ( 90% were achieved. The electrically treated device completely killed Escherichia coli and Staphylococcus aureus and SARS-CoV-2 pseudovirus within a few minutes at a low surface temperature of

While CD95 is an apoptosis-inducing receptor and has emerged as a potential anticancer therapy target, mounting evidence shows that CD95 is also emerging as a tumor promoter by activating nonapoptotic signaling pathways. Gammaherpesviral infection is closely associated with lymphoproliferative diseases, including B cell lymphomas. The nonapoptotic function of CD95 in gammaherpesvirus-associated lymphomas is largely unknown. Here, we show that stimulation of CD95 agonist antibody drives the majority of sensitive gammaherpesvirus-transformed B cells to undergo caspase-dependent apoptosis and promotes the survival and proliferation of a subpopulation of apoptosis-resistant B cells. Surprisingly, CD95-mediated nonapoptotic signaling induced beta interferon (IFN-β) expression and correlatively inhibited B cell receptor (BCR)-mediated gammaherpesviral replication in the apoptosis-resistant lymphoma cells without influencing BCR signaling. Further analysis showed that IFN-β alone or synergizing with CD95 blocked the activation of lytic switch proteins and the gene expression of gammaherpesviruses. Our findings indicate that, independent of its apoptotic activity, CD95 signaling activity plays an important role in blocking viral replication in apoptosis-resistant, gammaherpesvirus-associated B lymphoma cells, suggesting a novel mechanism that indicates how host CD95 prototype death receptor controls the life cycle of gammaherpesviruses independent of its apoptotic activity. IMPORTANCE Gammaherpesviruses are closely associated with lymphoid malignancies and other cancers. Viral replication and persistence strategies leading to cancer involve the activation of antiapoptotic and proliferation programs, as well as evasion of the host immune response. Here, we provide evidence that the stimulation of CD95 agonist antibody, mimicking one of the major mechanisms of cytotoxic T cell killing, inhibits B cell receptor-mediated gammaherpesviral replication in CD95 apoptosis-resistant lymphoma cells. CD95-induced type I interferon (IFN-β) contributes to the inhibition of gammaherpesviral replication. This finding sheds new light on the CD95 nonapoptotic function and provides a novel mechanism for gammaherpesviruses that helps them to escape host immune surveillance.