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Frontiers in Cellular and Infection... 2023Modified Vaccinia virus Ankara (MVA) represents a promising vaccine vector for respiratory administration to induce protective lung immunity including tertiary lymphoid...
BACKGROUND AND AIMS
Modified Vaccinia virus Ankara (MVA) represents a promising vaccine vector for respiratory administration to induce protective lung immunity including tertiary lymphoid structure, the bronchus-associated lymphoid tissue (BALT). However, MVA expressing the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Spike protein (MVA-SARS-2-S) required prime-boost administration to induce high titers of anti-Spike antibodies in serum and bronchoalveolar lavage (BAL). As the addition of adjuvants enables efficient tailoring of the immune responses even to live vaccines, we tested whether Toll-like receptor (TLR)-agonists affect immune responses induced by a single dose of intranasally applied MVA-SARS-2-S.
METHODS
We intranasally immunized C57BL/6 mice with MVA-SARS-2-S vaccine in the presence of either TLR3 agonist polyinosinic polycytidylic acid [poly(I:C)], TLR4 agonist bacterial lipopolysaccharide (LPS) from , or TLR9 agonist CpG oligodeoxynucleotide (CpG ODN) 1826. At different time-points after immunization, we analyzed induced immune responses using flow cytometry, immunofluorescent microscopy, and ELISA.
RESULTS
TLR agonists had profound effects on MVA-SARS-2-S-induced immune responses. At day 1 post intranasal application, the TLR4 agonist significantly affected MVA-induced activation of dendritic cells (DCs) within the draining bronchial lymph nodes, increasing the ratio of CD11bCD86 to CD103CD86 DCs. Nevertheless, the number of Spike-specific CD8 T cells within the lungs at day 12 after vaccination was increased in mice that received MVA-SARS-2-S co-administered with TLR3 but not TLR4 agonists. TLR9 agonist did neither significantly affect MVA-induced DC activation nor the induction of Spike-specific CD8 T cells but reduced both number and size of bronchus-associated lymphoid tissue. Surprisingly, the addition of all TLR agonists failed to boost the levels of Spike-specific antibodies in serum and bronchoalveolar lavage.
CONCLUSIONS
Our study indicates a potential role of TLR-agonists as a tool to modulate immune responses to live vector vaccines. Particularly TLR3 agonists hold a promise to potentiate MVA-induced cellular immune responses. On the other hand, additional research is necessary to identify optimal combinations of agonists that could enhance MVA-induced humoral responses.
Topics: Animals; Mice; SARS-CoV-2; Administration, Intranasal; CD8-Positive T-Lymphocytes; Toll-Like Receptor 3; Toll-Like Receptor 4; Toll-Like Receptor 9; Mice, Inbred C57BL; COVID-19; Vaccinia virus; Adjuvants, Immunologic; Vaccines; Antibodies, Viral
PubMed: 37854858
DOI: 10.3389/fcimb.2023.1259822 -
BioRxiv : the Preprint Server For... Apr 2024PARP14 is a 203 kDa multi-domain protein that is primarily known as an ADP-ribosyltransferase, and is involved in a variety of cellular functions including DNA damage,...
PARP14 is a 203 kDa multi-domain protein that is primarily known as an ADP-ribosyltransferase, and is involved in a variety of cellular functions including DNA damage, microglial activation, inflammation, and cancer progression. In addition, PARP14 is upregulated by interferon (IFN), indicating a role in the antiviral response. Furthermore, PARP14 has evolved under positive selection, again indicating that it is involved in host-pathogen conflict. We found that PARP14 is required for increased IFN-I production in response to coronavirus infection lacking ADP-ribosylhydrolase (ARH) activity and poly(I:C), however, whether it has direct antiviral function remains unclear. Here we demonstrate that the catalytic activity of PARP14 enhances IFN-I and IFN-III responses and restricts ARH-deficient murine hepatitis virus (MHV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) replication. To determine if PARP14's antiviral functions extended beyond CoVs, we tested the ability of herpes simplex virus 1 (HSV-1) and several negative-sense RNA viruses, including vesicular stomatitis virus (VSV), Ebola virus (EBOV), and Nipah virus (NiV), to infect A549 PARP14 knockout (KO) cells. HSV-1 had increased replication in PARP14 KO cells, indicating that PARP14 restricts HSV-1 replication. In contrast, PARP14 was critical for the efficient infection of VSV, EBOV, and NiV, with EBOV infectivity at less than 1% of WT cells. A PARP14 active site inhibitor had no impact on HSV-1 or EBOV infection, indicating that its effect on these viruses was independent of its catalytic activity. These data demonstrate that PARP14 promotes IFN production and has both pro- and anti-viral functions targeting multiple viruses.
PubMed: 38712082
DOI: 10.1101/2024.04.26.591186 -
Biomolecules Jun 2024MicroRNAs (miRNAs) are highly conserved endogenous single-stranded non-coding RNA molecules that play a crucial role in regulating gene expression to maintain normal...
Downregulation of miR-1388 Regulates the Expression of Antiviral Genes via Tumor Necrosis Factor Receptor ()-Associated Factor 3 Targeting Following poly(I:C) Stimulation in Silver Carp ().
MicroRNAs (miRNAs) are highly conserved endogenous single-stranded non-coding RNA molecules that play a crucial role in regulating gene expression to maintain normal physiological functions in fish. Nevertheless, the specific physiological role of miRNAs in lower vertebrates, particularly in comparison to mammals, remains elusive. Additionally, the mechanisms underlying the control of antiviral responses triggered by viral stimulation in fish are still not fully understood. In this study, we investigated the regulatory impact of miR-1388 on the signaling pathway mediated by IFN regulatory factor 3 (). Our findings revealed that following stimulation with the viral analog poly(I:C), the expression of miR-1388 was significantly upregulated in primary immune tissues and macrophages. Through a dual luciferase reporter assay, we corroborated a direct targeting relationship between miR-1388 and tumor necrosis factor receptor ()-associated factor 3 (). Furthermore, our study demonstrated a distinct negative post-transcriptional correlation between miR-1388 and . We observed a significant negative post-transcriptional regulatory association between miR-1388 and the levels of antiviral genes following poly(I:C) stimulation. Utilizing reporter plasmids, we elucidated the role of miR-1388 in the antiviral signaling pathway activated by . By intervening with siRNA-, we validated that miR-1388 regulates the expression of antiviral genes and the production of type I interferons () through its interaction with . Collectively, our experiments highlight the regulatory influence of miR-1388 on the -mediated signaling pathway by targeting post poly(I:C) stimulation. These findings provide compelling evidence for enhancing our understanding of the mechanisms through which fish miRNAs participate in immune responses.
Topics: Animals; MicroRNAs; Poly I-C; Carps; TNF Receptor-Associated Factor 3; Down-Regulation; Interferon Regulatory Factor-3; Gene Expression Regulation; Fish Proteins; Signal Transduction
PubMed: 38927097
DOI: 10.3390/biom14060694 -
Behavioural Brain Research Aug 2023Prenatal and early postnatal infection have been associated with changes in microglial activity and the development of psychiatric disorders. Here, we investigated the...
Prenatal and early postnatal infection have been associated with changes in microglial activity and the development of psychiatric disorders. Here, we investigated the effect of prenatal immune activation and postnatal immune challenge, alone and combined, on behavior and microglial cell density in female Wistar rats. Pregnant rats were injected with poly I:C to induce a maternal immune activation (MIA). Their female offspring were subsequently exposed to a lipopolysaccharide (LPS) immune challenge during adolescence. Anhedonia, social behavior, anxiety, locomotion, and working memory were measured with the sucrose preference, social interaction, open field, elevated-plus maze, and Y-maze test, respectively. Microglia cell density was quantified by counting the number of Iba-1 positive cells in the brain cortex. Female MIA offspring were more susceptible to the LPS immune challenge during adolescence than control offspring as demonstrated by a more pronounced reduction in sucrose preference and body weight on the days following the LPS immune challenge. Furthermore, only the rats exposed to both MIA and LPS showed long-lasting changes in social behavior and locomotion. Conversely, the combination MIA and LPS prevented the anxiety induced by MIA alone during adulthood. MIA, LPS, or their combination did not change microglial cell density in the parietal and frontal cortex of adult rats. The results of our study suggest that the maternal immune activation during pregnancy aggravates the response to an immune challenge during adolescence in female rats.
Topics: Pregnancy; Humans; Rats; Animals; Female; Rats, Wistar; Lipopolysaccharides; Prenatal Exposure Delayed Effects; Brain; Social Behavior; Behavior, Animal; Disease Models, Animal
PubMed: 37419332
DOI: 10.1016/j.bbr.2023.114566 -
Experimental & Molecular Medicine Feb 2024Circadian arrhythmia has been linked to increased susceptibility to multiple inflammatory diseases, such as sepsis. However, it remains unclear how disruption of the...
Circadian arrhythmia has been linked to increased susceptibility to multiple inflammatory diseases, such as sepsis. However, it remains unclear how disruption of the circadian clock modulates molecular aspects of innate immune responses, including inflammasome signaling. Here, we examined the potential role of the circadian clock in inflammasome-mediated responses through myeloid-specific deletion of BMAL1, a master circadian clock regulator. Intriguingly, Bmal1 deficiency significantly enhanced pyroptosis of macrophages and lethality of mice under noncanonical inflammasome-activating conditions but did not alter canonical inflammasome responses. Transcriptome analysis of enriched peritoneal myeloid cells revealed that Bmal1 deficiency led to a marked reduction in Rev-erbα expression at steady state and a significant increase in serum amyloid A1 (SAA1) expression upon poly(I:C) stimulation. Notably, we found that the circadian regulator Rev-erbα is critical for poly(I:C)- or interferon (IFN)-β-induced SAA1 production, resulting in the circadian oscillation pattern of SAA1 expression in myeloid cells. Furthermore, exogenously applied SAA1 markedly increased noncanonical inflammasome-mediated pyroptosis of macrophages and lethality of mice. Intriguingly, our results revealed that type 1 IFN receptor signaling is needed for poly(I:C)- or IFN-β-induced SAA1 production. Downstream of the type 1 IFN receptor, Rev-erbα inhibited the IFN-β-induced association of C/EBPβ with the promoter region of Saa1, leading to the reduced transcription of Saa1 in macrophages. Bmal1-deficient macrophages exhibited enhanced binding of C/EBPβ to Saa1. Consistently, the blockade of Rev-erbα by SR8278 significantly increased poly(I:C)-stimulated SAA1 transcription and noncanonical inflammasome-mediated lethality in mice. Collectively, our data demonstrate a potent suppressive effect of the circadian clock BMAL1 on the noncanonical inflammasome response via the Rev-erbα-C/EBPβ-SAA1 axis.
Topics: Animals; Mice; Inflammasomes; ARNTL Transcription Factors; Circadian Clocks; Pyroptosis; Immunity, Innate; CCAAT-Enhancer-Binding Protein-beta; Poly I-C
PubMed: 38297162
DOI: 10.1038/s12276-024-01162-w -
Biology of Reproduction Apr 2024Maternal immune activation during pregnancy is a risk factor for offspring neuropsychiatric disorders. Among the mechanistic pathways by which maternal inflammation can...
Maternal immune activation during pregnancy is a risk factor for offspring neuropsychiatric disorders. Among the mechanistic pathways by which maternal inflammation can affect fetal brain development and programming, those involving tryptophan (TRP) metabolism have drawn attention because various TRP metabolites have neuroactive properties. This study evaluates the effect of bacterial (lipopolysaccharides/LPS) and viral (polyinosinic:polycytidylic acid/poly I:C) placental infection on TRP metabolism using an ex vivo model. Human placenta explants were exposed to LPS or poly I:C, and the release of TRP metabolites was analyzed together with the expression of related genes and proteins and the functional activity of key enzymes in TRP metabolism. The rate-limiting enzyme in the serotonin pathway, tryptophan hydroxylase, showed reduced expression and functional activity in explants exposed to LPS or poly I:C. Conversely, the rate-limiting enzyme in the kynurenine pathway, indoleamine dioxygenase, exhibited increased activity, gene, and protein expression, suggesting that placental infection mainly promotes TRP metabolism via the kynurenine (KYN) pathway. Furthermore, we observed that treatment with LPS or poly I:C increased activity in the kynurenine monooxygenase branch of the KYN pathway. We conclude that placental infection impairs TRP homeostasis, resulting in decreased production of serotonin and an imbalance in the ratio between quinolinic acid and kynurenic acid. This disrupted homeostasis may eventually expose the fetus to suboptimal/toxic levels of neuroactive molecules and impair fetal brain development.
Topics: Humans; Pregnancy; Female; Placenta; Kynurenine; Tryptophan; Lipopolysaccharides; Serotonin; Poly I; Indoleamine-Pyrrole 2,3,-Dioxygenase
PubMed: 38145492
DOI: 10.1093/biolre/ioad181 -
Viruses Nov 2023HIV infection impairs host immunity, leading to progressive disease. An anti-retroviral treatment efficiently controls viremia but cannot completely restore the immune...
HIV infection impairs host immunity, leading to progressive disease. An anti-retroviral treatment efficiently controls viremia but cannot completely restore the immune dysfunction in HIV-infected individuals. Both host and viral factors determine the rate of disease progression. Among the host factors, innate immunity plays a critical role; however, the mechanism(s) associated with dysfunctional innate responses are poorly understood among HIV disease progressors, which was investigated here. The gene expression profiles of TLRs and innate cytokines in HIV-infected (LTNPs and progressors) and HIV-uninfected individuals were examined. Since the progressors showed a dysregulated TLR-mediated innate response, we investigated the role of TLR agonists in restoring the innate functions of the progressors. The stimulation of PBMCs with TLR3 agonist-poly:(I:C), TLR7 agonist-GS-9620 and TLR9 agonist-ODN 2216 resulted in an increased expression of IFN-α, IFN-β and IL-6. Interestingly, the expression of , , , was also increased upon stimulation with TLR3 and TLR7 agonists, respectively. To further understand the molecular mechanism involved, the role of miR-155 was explored. Increased miR-155 expression was noted among the progressors. MiR-155 inhibition upregulated the expression of TLR3, NF-κB, IRF-3, TNF-α and the , , and genes in the PBMCs of the progressors. To conclude, miR-155 negatively regulates TLR-mediated cytokines as wel l as the expression of host restriction factors, which play an important role in mounting anti-HIV responses; hence, targeting miR-155 might be helpful in devising strategic approaches towards alleviating HIV disease progression.
Topics: Humans; HIV Infections; Toll-Like Receptor 7; Toll-Like Receptor 3; Cytokines; Immunity, Innate; MicroRNAs; Disease Progression; Antiviral Agents; Membrane Proteins; RNA-Binding Proteins
PubMed: 38005883
DOI: 10.3390/v15112206 -
RNA Biology Jan 2024Double-stranded RNA (dsRNA) is a molecular pattern uniquely produced in cells infected with various viruses as a product or byproduct of replication. Cells detect such...
Double-stranded RNA (dsRNA) is a molecular pattern uniquely produced in cells infected with various viruses as a product or byproduct of replication. Cells detect such molecules, which indicate non-self invasion, and induce diverse immune responses to eliminate them. The degradation of virus-derived molecules can also play a role in the removal of pathogens and suppression of their replication. RNautophagy and DNautophagy are cellular degradative pathways in which RNA and DNA are directly imported into a hydrolytic organelle, the lysosome. Two lysosomal membrane proteins, SIDT2 and LAMP2C, mediate nucleic acid uptake via this pathway. Here, we showed that the expression of both and is selectively upregulated during the intracellular detection of poly(I:C), a synthetic analog of dsRNA that mimics viral infection. The upregulation of these two gene products upon poly(I:C) introduction was transient and synchronized. We also observed that the induction of and expression by poly(I:C) was dependent on MDA5, a cytoplasmic innate immune receptor that directly recognizes poly(I:C) and induces various antiviral responses. Finally, we showed that lysosomes can target viral RNA for degradation via RNautophagy and may suppress viral replication. Our results revealed a novel degradative pathway in cells as a downstream component of the innate immune response and provided evidence suggesting that the degradation of viral nucleic acids via RNautophagy/DNautophagy contributes to the suppression of viral replication.
Topics: Cytoplasm; RNA, Double-Stranded; Biological Transport; Cytosol; Immunity, Innate; Poly I-C; Receptors, Immunologic
PubMed: 38200692
DOI: 10.1080/15476286.2023.2291610 -
Translational Oncology Sep 2023Persistent human papillomavirus (HPV) infections is necessary for the development of cervical cancers. An increasing number of retrospective studies have found the...
Lactobacillus gasseri LGV03 isolated from the cervico-vagina of HPV-cleared women modulates epithelial innate immune responses and suppresses the growth of HPV-positive human cervical cancer cells.
Persistent human papillomavirus (HPV) infections is necessary for the development of cervical cancers. An increasing number of retrospective studies have found the depletion of Lactobacillus microbiota in the cervico-vagina facilitate HPV infection and might be involved in viral persistence and cancer development. However, there have been no reports confirming the immunomodulatory effects of Lactobacillus microbiota isolated from cervico-vaginal samples of HPV clearance in women. Using cervico-vaginal samples from HPV persistent infection and clearance in women, this study investigated the local immune properties in cervical mucosa. As expected, type I interferons, such as IFN-α and IFN-β, and TLR3 globally downregulated in HPV+ persistence group. Luminex cytokine/chemokine panel analysis revealed that L. jannaschii LJV03, L. vaginalis LVV03, L. reuteri LRV03, and L. gasseri LGV03 isolated from cervicovaginal samples of HPV clearance in women altered the host's epithelial immune response, particularly L. gasseri LGV03. Furthermore, L. gasseri LGV03 enhanced the poly (I:C)-induced production of IFN by modulating the IRF3 pathway and attenuating poly (I:C)-induced production of proinflammatory mediators by regulating the NF-κB pathway in Ect1/E6E7 cells, indicating that L. gasseri LGV03 keeps the innate system alert to potential pathogens and reduces the inflammatory effects during persistent pathogen infection. L. gasseri LGV03 also markedly inhibited the proliferation of Ect1/E6E7 cells in a zebrafish xenograft model, which may be attributed to an increased immune response mediated by L. gasseri LGV03.
PubMed: 37331103
DOI: 10.1016/j.tranon.2023.101714 -
Molecular Therapy. Nucleic Acids Mar 2024Autism is a widespread neurodevelopmental disorder. Although the research on autism spectrum disorders has been increasing in the past decade, there is still no specific...
Autism is a widespread neurodevelopmental disorder. Although the research on autism spectrum disorders has been increasing in the past decade, there is still no specific answer to its mechanism of action and treatment. As a pro-inflammatory microRNA, miR-301a is abnormally expressed in various psychiatric diseases including autism. Here, we show that miR-301a deletion and inhibition exhibited two distinct abnormal behavioral phenotypes in mice. We observed that miR-301a deletion in mice impaired learning/memory, and enhanced anxiety. On the contrary, miR-301a inhibition effectively reduced the maternal immune activation (MIA)-induced autism-like behaviors in mice. We further demonstrated that miR-301a bound to the 3'UTR region of the SOCS3, and that inhibition of miR-301a led to the upregulation of SOCS3 in hippocampus. The last result in the reduction of the inflammatory response by inhibiting phosphorylation of AKT and STAT3, and the expression level of IL-17A in poly(I:C)-induced autism-like features in mice. The obtained data revealed the miR-301a as a critical participant in partial behavior phenotypes, which may exhibit a divergent role between gene knockout and knockdown. Our findings ascertain that miR-301a negatively regulates SOCS3 in MIA-induced autism in mice and could present a new therapeutic target for ameliorating the behavioral abnormalities of autism.
PubMed: 38439911
DOI: 10.1016/j.omtn.2024.102136