RESUMO
Influenza A virus (IAV) H1N1 infection is a constant threat to human health and it remains so due to the lack of an effective treatment. Since melatonin is a potent antioxidant and anti-inflammatory molecule with anti-viral action, in the present study we used melatonin to protect against H1N1 infection under in vitro and in vivo conditions. The death rate of the H1N1-infected mice was negatively associated with the nose and lung tissue local melatonin levels but not with serum melatonin concentrations. The H1N1-infected AANAT-/- melatonin-deficient mice had a significantly higher death rate than that of the WT mice and melatonin administration significantly reduced the death rate. All evidence confirmed the protective effects of melatonin against H1N1 infection. Further study identified that the mast cells were the primary targets of melatonin action, i.e., melatonin suppresses the mast cell activation caused by H1N1 infection. The molecular mechanisms involved melatonin down-regulation of gene expression for the HIF-1 pathway and inhibition of proinflammatory cytokine release from mast cells; this resulted in a reduction in the migration and activation of the macrophages and neutrophils in the lung tissue. This pathway was mediated by melatonin receptor 2 (MT2) since the MT2 specific antagonist 4P-PDOT significantly blocked the effects of melatonin on mast cell activation. Via targeting mast cells, melatonin suppressed apoptosis of alveolar epithelial cells and the lung injury caused by H1N1 infection. The findings provide a novel mechanism to protect against the H1N1-induced pulmonary injury, which may better facilitate the progress of new strategies to fight H1N1 infection or other IAV viral infections.
Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Lesão Pulmonar , Melatonina , Infecções por Orthomyxoviridae , Humanos , Animais , Camundongos , Lesão Pulmonar/tratamento farmacológico , Lesão Pulmonar/metabolismo , Mastócitos/metabolismo , Melatonina/farmacologia , Melatonina/metabolismo , Síndrome da Liberação de Citocina/metabolismo , PulmãoRESUMO
Fast evolution in the field of the replicase nsp2 represents a most prominent feature of porcine reproductive and respiratory syndrome virus (PRRSV). Here, we determined its biological significance in viral pathogenesis by constructing interlineage chimeric mutants between the Chinese highly pathogenic PRRSV (HP-PRRSV) strain JXwn06 (lineage 8) and the low-virulent NADC30-like strain CHsx1401 (lineage 1). Replacement with nsp2 from JXwn06 was surprisingly lethal to the backbone virus CHsx1401, but combined substitution with the structural protein-coding region (SP) gave rise to viable virus CHsx1401-SPnsp2JX. Meanwhile, a derivative carrying only the SP region (CHsx1401-SPJX) served as a control. Subsequent animal experiments revealed that acquisition of SP alone (CHsx1401-SPJX) did not allow CHsx1401 to gain much virulence, but additional swapping of HP-PRRSV nsp2 (CHsx1401-SPnsp2JX) enabled CHsx1401 to acquire some properties of HP-PRRSV, exemplified by prolonged high fever, microscopic lung hemorrhage, and a significant increase in proinflammatory cytokines in the acute stage. Consistent with this was the transcriptomic analysis of persistently infected secondary lymphoid tissues that revealed a much stronger induction of host cellular immune responses in this group and identified several core immune genes (e.g., TLR4, IL-1ß, MPO, etc.) regulated by HP-PRRSV nsp2. Interestingly, immune activation status in the individual groups correlated well with the rate of viremia clearance and viral tissue load reduction. Overall, the above results suggest that the Chinese HP-PRRSV nsp2 is a critical virulence regulator and highlight the importance of nsp2 genetic variation in modulating PRRSV virulence and persistence via immune modulation. IMPORTANCE Porcine reproductive and respiratory syndrome virus (PRRSV) has been a major threat to the world swine industry. In the field, rapid genetic variations (e.g., deletion, mutation, recombination, etc.) within the nsp2 region present an intriguing conundrum to PRRSV biology and pathogenesis. By making chimeric mutants, here, we show that the Chinese highly pathogenic PRRSV (HP-PRRSV) nsp2 is a virulence factor and a much stronger inducer of host immune responses (e.g., inflammation) than its counterpart, currently epidemic, NADC30-like strains. Differences in the ability to modulate host immunity provide insight into the mechanisms of why NADC30-like strains and their derivatives are rising to be the dominant viruses, whereas the Chinese HP-PRRSV strains gradually give away center stage in the field. Our results have important implications in understanding PRRSV evolution, interlineage recombination, and persistence.
Assuntos
Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Animais , China/epidemiologia , Citocinas , Variação Genética , Genoma Viral , Filogenia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Suínos , Virulência/genéticaRESUMO
The Influenza A virus (IAV) is a zoonotic pathogen that infects humans and various animal species. Infection with IAV can cause fever, anorexia, and dyspnea and is often accompanied by pneumonia characterized by an excessive release of cytokines (i.e., cytokine storm). Nanodrug delivery systems and nanoparticles are a novel approach to address IAV infections. Herein, UiO-66 nanoparticles (NPs) are synthesized using a high-temperature melting reaction. The in vitro and in vivo optimal concentrations of UiO-66 NPs for antiviral activity are 200 µg mL-1 and 60 mg kg-1, respectively. Transcriptome analysis revealed that UiO-66 NPs can activate the RIG-I-like receptor signaling pathway, thereby enhancing the downstream type I interferon antiviral effect. These NPs suppress inflammation-related pathways, including the FOXO, HIF, and AMPK signaling pathways. The inhibitory effect of UiO-66 NPs on the adsorption and entry of IAV into A549 cells is significant. This study presents novel findings that demonstrate the effective inhibition of IAV adsorption and entry into cells via UiO-66 NPs and highlights their ability to activate the cellular RIG-I-like receptor signaling pathway, thereby exerting an anti-IAV effect in vitro or in mice. These results provide valuable insights into the mechanism of action of UiO-66 NPs against IAV and substantial data for advancing innovative antiviral nanomedicine.
Assuntos
Vírus da Influenza A , Influenza Humana , Estruturas Metalorgânicas , Infecções por Orthomyxoviridae , Ácidos Ftálicos , Camundongos , Humanos , Animais , Infecções por Orthomyxoviridae/tratamento farmacológico , Transdução de Sinais , Antivirais/farmacologia , Antivirais/uso terapêuticoRESUMO
The furin cleavage site plays an important role in virus pathogenicity. The spike protein of SARS-CoV-2 harbors a furin cleavage site insertion in contrast to SARS-CoV, which may be related to its stronger communicability. An avian coronavirus with an extra furin cleavage site upstream of the fusion peptide (S2' site) infected monocyte cells and neuron cells leading to viremia or encephalitis, respectively. Immunohistochemistry and real-time quantitative polymerase chain reaction were used to follow disease progression and demonstrated differences between the parent avian coronavirus and mutated avian coronavirus with a furin-S2' site. Magnetic resonance imaging and biological dye to evaluate the blood-brain barrier permeability showed that avian coronavirus with a furin-S2' site had increased permeability compared with parent avian coronavirus. Immunohistochemistry of brains after intracerebral injection of avian coronavirus and immunofluorescence staining of primary neuron cells demonstrated the furin-S2' site expanded the cell tropism of the mutant avian coronavirus to neuron cells. TNF-α, which has a key role in blood-brain barrier permeability, was highly induced by avian coronavirus with a furin-S2' site compared with the parent avian coronavirus. We demonstrated the process involved in mutant avian coronavirus-induced disease and that the addition of a furin-S2' site changed the virus cell tropism.IMPORTANCECoronaviruses have broken out three times in two decades. Spike (S) protein plays a key role in the process of infection. To clarify importance of furin cleavage site in spike protein for coronavirus, we investigated the pathogenesis of neurotropic avian coronavirus whose spike protein contains an extra furin cleavage site (furin-S2' site). By combining real-time quantitative polymerase chain reaction and immunohistochemistry we demonstrated that infectious bronchitis virus (IBV) infects brain instead of trachea when its S protein contains furin-S2' site. Moreover, the virus was shown to increase the permeability of blood-brain barrier, infect neuron cells and induce high expression of TNF-α. Based on these results we further show that furin cleavage site in S protein plays an important role in coronavirus pathogenicity and cell tropism. Our study extends previous publications on function of S protein of coronavirus, increasing the understanding of researchers to coronavirus.
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Four fluorimetric probes had been developed to rapidly detect 2,4,6-trinitrophenol (TNP). They were designed and synthesized on the basis of 1,3,4-thiadiazole framework combining calculation with experiment. Among them, SK-1 displayed strong blue emission with fluorescence quantum yield as high as 63.6% in solution. Further evaluation demonstrated that SK-1 displays good selectivity and high sensitivity for rapid and visual detection of TNP. It brought significant changes in both colour and fluorescence emission spectrum. The detection limit was as low as 38 nM. Quenching mechanism was confirmed as photo-induced electron transfer (PET) by nuclear magnetic titration and DFT calculations. What's more, application in real water samples and solid phase paper tests illustrated the practical significance of detection of TNP in both vapor and solution.
Assuntos
Espectrometria de Fluorescência , Teoria da Densidade Funcional , Picratos , TiadiazóisRESUMO
Intestinal homeostasis is maintained through the interplay of the intestinal mucosa, local and systemic immune factors, and the microbial content of the gut. Iron is a trace mineral in most organisms, including humans, which is essential for growth, systemic metabolism and immune response. Paradoxically, excessive iron intake and/or high iron status can be detrimental to iron metabolism in the intestine and lead to iron overload and ferroptosis-programmed cell death mediated by iron-dependent lipid peroxidation within cell membranes, which contributes to several intestinal diseases. In this review, we comprehensively review recent findings on the impacts of iron overload and ferroptosis on intestinal mucosal homeostasis and inflammation and then present the progress of iron overload and ferroptosis-targeting therapy in intestinal diseases. Understanding the involved mechanisms can provide a new understanding of intestinal disease pathogenesis and facilitate advanced preventive and therapeutic strategies for intestinal dysfunction and diseases.
Assuntos
Ferroptose , Sobrecarga de Ferro , Humanos , Homeostase , Inflamação , Ferro/metabolismo , Mucosa Intestinal/metabolismoRESUMO
Influenza A virus (IAV) can cause high morbidity and mortality globally every year. Myriad host kinases and their related signaling pathways are involved in IAV infection, and the important role of the c-Jun N-terminal kinase signaling pathway during infection has been demonstrated. SP600125, an inhibitor of c-Jun N-terminal kinase, was found in our previous study to suppress IAV replication in vitro. In this study, we established a mouse model of H1N1 IAV infection and treated the mice with SP600125 to study its protective effect. The results showed that SP600125 treatment reduced the pulmonary inflammatory response, lung injury, and pulmonary viral load and increased the survival rate of H1N1-infected mice. Our data confirm the crucial role of c-Jun N terminal kinase in H1N1 virus replication and inflammatory responses in vivo. Hence, we speculate that SP600125 has a potential antiviral therapeutic benefit against IAV infection.
Assuntos
Antracenos/administração & dosagem , Vírus da Influenza A Subtipo H1N1/fisiologia , Infecções por Orthomyxoviridae/tratamento farmacológico , Animais , Antracenos/farmacologia , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Pulmão/virologia , Camundongos , Infecções por Orthomyxoviridae/virologia , Proteínas Proto-Oncogênicas c-jun/metabolismo , Distribuição Aleatória , Resultado do Tratamento , Replicação Viral/efeitos dos fármacosRESUMO
With the globe warming, chronic heat stress (CHS) has been considered to be a common hazard that could negatively affect pig's growth and reproduction performance. However, the effects of CHS on the immune functions of pigs were seldom reported, especially the cellular immune functions of intestinal mucosal system. In order to resolve this problem, a pig CHS model was built firstly and the effects of CHS on numbers of T cells in spleen and small intestines were observed. Exposure to a temperature of 39⯰C, 4â¯h/d for 10d, the expression of heat stress protein 70 (HSP70) was increased dramatically. Under CHS condition, the numbers of CD3+ T cells were increased dramatically in both spleens and small intestines. Besides, the numbers of CD4+T cells and the value of CD4+/CD8+T cells in spleens were also significantly increased. The results highly revealed that CHS made the equilibrium state of immune function destroyed. Furthermore, CHS mainly promoted the expression of anti-apoptosis factor B cell lymphoma-2 (Bcl-2) and thus inhibited the apoptosis of lymphocytes in spleens and intestinal mucosa. This study demonstrates for the first time that CHS negatively affects the immune functions of both spleens and intestinal mucosal system in pigs through the inhibition of apoptosis. Our study can richer the data for study of mechanism of CHS and provide new knowledge for reference of making new strategy to control the disease induced by CHS.
Assuntos
Apoptose/efeitos da radiação , Resposta ao Choque Térmico , Mucosa Intestinal/imunologia , Mucosa Intestinal/efeitos da radiação , Baço/imunologia , Baço/efeitos da radiação , Animais , Temperatura Alta , Suínos , Fatores de TempoRESUMO
The current study was to identify a protective role of Shuanghuanglian (SHL) injection powder in vitro and in vivo after H5N1 viral infection. Immunofluorescent staining was used to determine the susceptibility of rat intestinal mucosa microvascular endothelial cells (RIM-MVECs) to the H5N1 virus. Viral replication of RIM-MVECs was measured by transmission electron microscopy (TEM) a hemagglutination assay and real-time quantitative PCR. H5N1 virally infected RIM-MVECs, and BALB/c mice were treated with SHL to investigate its therapeutic effect. Animal survival and the weight of H5N1 virally infected BALB/c mice after SHL treatment was noted, and histology and real-time PCR applied to mouse lungs were used to confirm the anti-H5N1 viral effects of SHL. RIM-MVECs supported replication of the H5N1 virus in vitro. SHL treatment reduced viral titers in H5N1 virally infected RIM-MVECs and mouse lungs. SHL -treated mice survived compared to controls. Mild pathological changes, reduced inflammatory cell infiltration and fewer viral antigens were observed in the lungs of SHL-treated mice at days 3 and 6 post-infection. In conclusion, SHL may have the antiviral activity against the H5N1 virus infection by inhibiting viral replication and alleviating lung injury.
Assuntos
Antivirais/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Virus da Influenza A Subtipo H5N1/efeitos dos fármacos , Infecções por Orthomyxoviridae/tratamento farmacológico , Animais , Linhagem Celular , Células Endoteliais/efeitos dos fármacos , Feminino , Pulmão/efeitos dos fármacos , Pulmão/virologia , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Ratos , Replicação ViralRESUMO
Type 1 diabetes (T1D) is a metabolic disease induced by abnormal insulin secretions from damaged islet B cells. Clinical observations have shown that T1D patients are more easily infected by influenza A virus (IAV) and suffer more serious symptoms than non-T1D patients. To investigate the susceptibility of T1D mice to IAV, a T1D mouse model was built by intraperitoneal injection of diluted streptozotocin (STZ) over 5 consecutive days, followed by infection with three subtypes of IAV (H1N1/H5N1/H7N2). The T1D-infected mice showed more serious clinical symptoms and lower survival rates than the non-T1D infected mice. The hematoxylin and eosin (H&E) staining results revealed an increase in serious pathological damage to the lung and pancreas in T1D-infected mice. Immunohistochemistry results indicated higher IAV loads and a more extensive distribution of positive signals in the lungs and pancreas of T1D-infected mice than in those of non-T1D infected mice. Furthermore, according to real-time quantitative polymerase chain reaction (PCR) results, viral replication appeared to occur more easily in the lungs of T1D-infected mice. Thus, T1D-infected mice exhibited higher susceptibility to IAV than did normal mice. This study contributes a mouse model suitable for T1D research as well as valuable information about the mechanism underlying T1D patients' increased susceptibility to IAV.
Assuntos
Diabetes Mellitus Tipo 1/complicações , Suscetibilidade a Doenças , Vírus da Influenza A/patogenicidade , Infecções por Orthomyxoviridae/complicações , Infecções por Orthomyxoviridae/virologia , Animais , Glicemia/análise , Modelos Animais de Doenças , Ingestão de Líquidos , Células Epiteliais/patologia , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1/patogenicidade , Virus da Influenza A Subtipo H5N1/patogenicidade , Vírus da Influenza A Subtipo H7N2/patogenicidade , Pulmão/patologia , Pulmão/virologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/patologia , Pâncreas/patologia , Pâncreas/virologia , Estreptozocina/farmacologia , Taxa de Sobrevida , Carga Viral , Replicação ViralRESUMO
This study presents the first investigation of the antiviral effects of the liposome-encapsulated PolyICLC (LE-PolyICLC) on Dengue virus (DENV) in a mouse model. In vivo efficacy studies showed that LE-PolyICLC acted to increase antiviral mechanisms mainly through promoting cytokine expression associated with innate immunity, such as IFN-γ. In addition, the pro-inflammatory cytokine TNF-α was also increased, while IL-6 level was decreased in serum. The titers of total antibodies against DENV2 in mice were also elevated. Administration of LE-PolyICLC not only alleviated the loss of body weight, degree of morbidity, and pathological damage in brains, but also reduced the viral titers and expression of viral E protein in the brain. Notably, the effectiveness of LE-PolyICLC was better than PolyICLC on the basis of the data presented in this study. These results, therefore, set a foundation for further development of LE-PolyICLC as an attractive candidate of antiviral agents to be used in both prophylactic and therapeutic settings in DENV diseases.
Assuntos
Antivirais/farmacologia , Antivirais/uso terapêutico , Carboximetilcelulose Sódica/análogos & derivados , Vírus da Dengue/efeitos dos fármacos , Dengue/tratamento farmacológico , Dengue/virologia , Poli I-C/farmacologia , Poli I-C/uso terapêutico , Polilisina/análogos & derivados , Animais , Formação de Anticorpos/efeitos dos fármacos , Antígenos Virais/metabolismo , Encéfalo/patologia , Carboximetilcelulose Sódica/farmacologia , Carboximetilcelulose Sódica/uso terapêutico , Citocinas/metabolismo , Modelos Animais de Doenças , Lipossomos , Camundongos , Camundongos Endogâmicos BALB C , Polilisina/farmacologia , Polilisina/uso terapêutico , RNA Viral/metabolismo , Replicação Viral/efeitos dos fármacosRESUMO
The activation of c-jun N-terminal kinases (JNK) was previously shown to be required for efficient influenza A virus replication, although a detailed mechanism has not been reported. In this study, we found that replication of H5N1 influenza virus was influenced by the JNK inhibitor SP600125. The results of time course experiments suggested that SP600125 inhibited an early post-entry step of viral infection but did not affect nucleocytoplasmic trafficking of the viral ribonucleoprotein complex. The levels of influenza virus genomic RNA (vRNA), but not the corresponding cRNA or mRNA, were specifically reduced by SP600125 in virus-infected cells, indicating that the JNK protein is intimately involved in vRNA synthesis. Additionally, SP600125 affected H5N1 virus protein synthesis, because NS1, PB1, PB2, HA and M1 protein production was impaired. Thus, our data demonstrated a critical role of the JNK protein in the regulation of vRNA and protein synthesis during virus infection. This enhances our understanding of the complicated signal transduction network involved in influenza A virus replication.
Assuntos
Interações Hospedeiro-Patógeno , Virus da Influenza A Subtipo H5N1/fisiologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , RNA Viral/biossíntese , Proteínas Virais/biossíntese , Replicação Viral , Animais , Linhagem Celular , Cães , HumanosRESUMO
The cytokine storm which is a great burden on humanity in highly pathogenic influenza virus infections requires activation of multiple signaling pathways. These pathways, such as MAPK and JNK, are important for viral replication and host inflammatory response. Here we examined the roles of JNK downstream molecule c-jun in host inflammatory responses and H5N1 virus replication using a c-jun targeted DNAzyme (Dz13). Transfection of Dz13 significantly reduced H5N1 influenza virus replication in human lung epithelial cells. Concomitantly, there was a decreased expression of pro-inflammatory cytokines (tumor necrosis factor (TNF)-α, interferon (IFN)-ß and interleukin (IL)-6) in c-jun suppressed cells, while the expression of anti-inflammatory cytokines, such as IL-10, was increased. In vivo, compared with control groups, suppression of c-jun improved the survival rate of mice infected with H5N1 virus (55.5% in Dz13 treated mice versus ≤11% of control mice) and decreased the CD8(+) T cell proliferation. Simultaneously, the pulmonary inflammatory response and viral burden also decreased in the Dz13 treated group. Thus, our data demonstrated a critical role for c-jun in the establishment of H5N1 infection and subsequent inflammatory reactions, which suggest that c-jun may be a potential therapeutic target for viral pneumonia.
Assuntos
Inflamação/imunologia , Virus da Influenza A Subtipo H5N1/imunologia , Infecções por Orthomyxoviridae/imunologia , Proteínas Proto-Oncogênicas c-jun/imunologia , Replicação Viral/imunologia , Animais , Antracenos/farmacologia , Western Blotting , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Citocinas/genética , Citocinas/imunologia , Citocinas/metabolismo , Cães , Feminino , Técnicas de Silenciamento de Genes , Interações Hospedeiro-Patógeno/imunologia , Humanos , Inflamação/genética , Virus da Influenza A Subtipo H5N1/fisiologia , Células Madin Darby de Rim Canino , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/virologia , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de SobrevidaRESUMO
For over three decades, there has been a continuing panzootic caused by a virulent variant avian paramyxovirus type 1 strain, the so-called pigeon paramyxovirus type 1. It is found primarily in racing pigeons, but it has also spread to wild birds and poultry. In this study, two pigeon paramyxovirus type 1 strains, SD12 and BJ13, obtained from diseased pigeons in China, were characterized. Phylogenetic analysis based on complete sequences allowed characterization of both strains as genotype VI, class II. Further phylogenetic analysis of a 374-nucleotide section of the fusion gene showed that SD12 fell into lineage VIbii-d and BJ13 into VIbii-f. The deduced amino acid sequence of the cleavage site of the fusion protein confirmed that both isolates contained the virulent motif (112)K/RRQKR↓F(117) at the cleavage site. Nevertheless, the values of intracerebral pathogenicity indices showed the SD12 isolate to be a velogenic strain and BJ13 isolate to be a mesogenic strain. The SD12 isolate was further investigated via clinical observation, RNA detection, histopathology and viral serology in experimentally infected 3-week-old chickens. It showed a mild pathological phenotype in chickens, with viral replication restricted to a few tissues. The molecular mechanism for the SD12 isolate to have a virulent motif but low levels of virulence for chickens requires further study.
Assuntos
Columbidae , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/genética , Filogenia , Animais , Sequência de Bases , China , Clonagem Molecular , Análise por Conglomerados , Primers do DNA/genética , Modelos Genéticos , Dados de Sequência Molecular , Doença de Newcastle/patologia , Vírus da Doença de Newcastle/patogenicidade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA/veterinária , Especificidade da EspécieRESUMO
OBJECTIVES: Influenza in humans is often accompanied by gastroenteritis-like symptoms such as diarrhea and abdominal pain nausea, but the underlying mechanism remains unclear. RESULTS: Mice infected with three subtypes of respiratory influenza A virus (IAV), particularly H5N1 and H7N2, developed intestinal injury. The avian H5N1 and H7N2 IAV were detected in the small intestine, whereas the human H1N1 was not detected. Section staining with the sialic acid (SA) receptor demonstrated that the small intestine mainly expressed SA α2, 3 Gal instead of SA α2, 6 Gal which preferentially binds to avian IAV. The number of goblet and sIgA cells in the small intestine increased, whereas CD4(+) and CD8(+) T cells decreased in all infected mice except for CD8(+) T cells increased in H7N2 infected mice. CONCLUSIONS: Respiratory IAV infection, particularly infected by avian IAV, can cause small intestine structural damage and modify the local immune response, thereby resulting in gastroenteritis-like symptoms.
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Gastroenterite/etiologia , Gastroenterite/patologia , Infecções por Orthomyxoviridae/complicações , Infecções por Orthomyxoviridae/virologia , Infecções Respiratórias/complicações , Infecções Respiratórias/virologia , Animais , Linfócitos B/química , Linfócitos T CD4-Positivos/fisiologia , Linfócitos T CD8-Positivos/fisiologia , Modelos Animais de Doenças , Gastroenterite/virologia , Células Caliciformes/fisiologia , Imunoglobulina A Secretora/análise , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Virus da Influenza A Subtipo H5N1/isolamento & purificação , Vírus da Influenza A Subtipo H7N2/isolamento & purificação , Intestino Delgado/química , Intestino Delgado/patologia , Contagem de Leucócitos , Camundongos , Ácidos Siálicos/análiseRESUMO
H9N2 influenza viruses have been circulating worldwide in multiple avian species and repeatedly infecting mammals, including pigs and humans, posing a significant threat to public health. The coexistence of H9N2 and pandemic influenza H1N1/2009 viruses in pigs and humans provides an opportunity for these viruses to reassort. To evaluate the potential public risk of the reassortant viruses derived from these viruses, we used reverse genetics to generate 127 H9 reassortants derived from an avian H9N2 and a pandemic H1N1 virus, and evaluated their compatibility, replication ability, and virulence in mice. These hybrid viruses showed high genetic compatibility and more than half replicated to a high titer in vitro. In vivo studies of 73 of 127 reassortants revealed that all viruses were able to infect mice without prior adaptation and 8 reassortants exhibited higher pathogenicity than both parental viruses. All reassortants with higher virulence than parental viruses contained the PA gene from the 2009 pandemic virus, revealing the important role of the PA gene from the H1N1/2009 virus in generating a reassortant virus with high public health risk. Analyses of the polymerase activity of the 16 ribonucleoprotein combinations in vitro suggested that the PA of H1N1/2009 origin also enhanced polymerase activity. Our results indicate that some avian H9-pandemic reassortants could emerge with a potentially higher threat for humans and also highlight the importance of monitoring the H9-pandemic reassortant viruses that may arise, especially those that possess the PA gene of H1N1/2009 origin.
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Vírus da Influenza A Subtipo H1N1/patogenicidade , Vírus da Influenza A Subtipo H9N2/patogenicidade , Vírus Reordenados/patogenicidade , Animais , Genes Virais , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/fisiologia , Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A Subtipo H9N2/fisiologia , Camundongos , Dados de Sequência Molecular , Replicação ViralRESUMO
Background: A successful immune response against tumors depends on various cellular processes. Hence, there is an urgent need to construct a proficient nanoplatform for immunotherapy that can concurrently regulate the activities of various cells participating in the immune process. We have developed zeolitic imidazolate framework-8 (ZIF-8) formula, with good pH sensitivity, which is conducive to the release of drugs in the tumor site (acidic environment) and significantly improves immunotherapy. This is achieved through the coordinated action of different therapeutic agents, such as the photothermal agent polydopamine (PDA), the chemodrug camptothecin (CPT), and the immunomodulator 1-methyl-D-tryptophan (1-MT). Materials and Methods: In this study, we evaluated the antitumor effect of PDA/(CPT + 1-MT) @ZIF-8 (PCMZ) nanoparticles (NPs) in vitro and in vivo and investigated the molecular mechanism of PCMZ NPs in tumor suppression via photothermal-chemo-immunotherapy. Results: MTT and Annexin V-FITC/PI double staining apoptosis test showed that PCMZ NPs could induce apoptosis of 4T1 cell, and PCMZ NPs could cause 4T1 cell necrosis under 808 nm laser irradiation. The objective is to establish a unilateral breast cancer model in mice and investigate the effect of PCMZ NPs on tumor growth and tumor suppression in tumor bearing mice. The results showed that PCMZ NPs showed good heating effect in vivo and effectively inhibited tumor growth under 808 nm laser irradiation. In addition, PCMZ NPs could induce the immunogenic death of tumor cells, promote the maturation of DCs, inhibit IDO pathway, and finally differentiate T cells into cytotoxic T cells and helper T cells, so as to effectively activate the anti-tumor immune response. Conclusion: The PCMZ NPs, possessing good photothermal conversion capabilities due to join of PDA, effectively overcome two main challenges in immunotherapy: insufficient stimulation of the immune response and evasion of the immune system. This provides a robust platform against invasive cancer and recurrent tumors.
Assuntos
Camptotecina , Imunoterapia , Indóis , Camundongos Endogâmicos BALB C , Polímeros , Triptofano , Zeolitas , Animais , Indóis/química , Indóis/farmacologia , Zeolitas/química , Zeolitas/farmacologia , Imunoterapia/métodos , Triptofano/química , Triptofano/farmacologia , Triptofano/análogos & derivados , Camundongos , Concentração de Íons de Hidrogênio , Linhagem Celular Tumoral , Feminino , Polímeros/química , Polímeros/farmacologia , Camptotecina/química , Camptotecina/farmacologia , Nanopartículas/química , Apoptose/efeitos dos fármacos , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Humanos , Terapia Fototérmica/métodos , Imidazóis/química , Imidazóis/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Terapia CombinadaRESUMO
BTB and CNC homology 1 (BACH1) regulates biological processes, including energy metabolism and oxidative stress. Insufficient liver regeneration after hepatectomy remains an issue for surgeons. The Pringle maneuver is widely used during hepatectomy and induces ischemia/reperfusion (I/R) injury in hepatocytes. A rat model of two-thirds partial hepatectomy with repeated I/R treatment was used to simulate clinical hepatectomy with Pringle maneuver. Delayed recovery of liver function after hepatectomy with the repeated Pringle maneuver in clinic and impaired liver regeneration in rat model were observed. Highly elevated lactate levels, along with reduced mitochondrial complex III and IV activities in liver tissues, indicated that the glycolytic phenotype was promoted after hepatectomy with repeated I/R. mRNA expression profile analysis of glycolysis-related genes in clinical samples and further verification experiments in rat models showed that high BACH1 expression levels correlated with the glycolytic phenotype after hepatectomy with repeated I/R. BACH1 overexpression restricted the proliferative potential of hepatocytes stimulated with HGF. High PDK1 expression and high lactate levels, together with low mitochondrial complex III and IV activities and reduced ATP concentrations, were detected in BACH1-overexpressing hepatocytes with HGF stimulation. Moreover, HO-1 expression was downregulated, and oxidative stress was exacerbated in the BACH1-overexpressing hepatocytes with HGF stimulation. Cell experiments involving repeated hypoxia/reoxygenation revealed that reactive oxygen species accumulation triggered the TGF-ß1/BACH1 axis in hepatocytes. Finally, inhibiting BACH1 with the inhibitor hemin effectively restored the liver regenerative ability after hepatectomy with repeated I/R. These results provide a potential therapeutic strategy for impaired liver regeneration after repeated I/R injury.
Assuntos
Fatores de Transcrição de Zíper de Leucina Básica , Metabolismo Energético , Hepatectomia , Hepatócitos , Regeneração Hepática , Estresse Oxidativo , Ratos Sprague-Dawley , Traumatismo por Reperfusão , Animais , Humanos , Masculino , Ratos , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Metabolismo Energético/fisiologia , Hepatócitos/metabolismo , Regeneração Hepática/fisiologia , Estresse Oxidativo/fisiologia , Traumatismo por Reperfusão/metabolismoRESUMO
Although an important role for mast cells in several viral infections has been demonstrated, its role in the invasion of highly pathogenic H5N1 influenza virus is unknown. In the present study, we demonstrate that mast cells were activated significantly by H5N1 virus (A/chicken/Henan/1/2004) infection both in vivo and in vitro. Mast cells could possibly intensify the lung injury that results from H5N1 infection by releasing proinflammatory mediators, including histamine, tryptase, and gamma interferon (IFN-γ). Lung lesions and apoptosis induced by H5N1 infection were reduced dramatically by treatment with ketotifen, which is a mast cell degranulation inhibitor. A combination of ketotifen and the neuraminidase inhibitor oseltamivir protected 100% of the mice from death postinfection. In conclusion, our data suggest that mast cells play a crucial role in the early stages of H5N1 influenza virus infection and provide a new approach to combat highly pathogenic influenza virus infection.
Assuntos
Virus da Influenza A Subtipo H5N1/fisiologia , Influenza Humana/imunologia , Lesão Pulmonar/imunologia , Mastócitos/imunologia , Animais , Feminino , Humanos , Virus da Influenza A Subtipo H5N1/imunologia , Influenza Humana/complicações , Influenza Humana/virologia , Lesão Pulmonar/etiologia , Lesão Pulmonar/virologia , Mastócitos/virologia , Camundongos , Camundongos Endogâmicos BALB CRESUMO
Although IL-17 is a key factor in Th17 lineage host responses and plays critical roles in immunological control of a variety of infectious diseases, the contribution of IL-17 to immune function during Eimeria tenella infection is unknown. In the present study, we used an experimental E. tenella infection model to clarify the role of Th17-associated response in the resulting immune response by quantitative real-time PCR assays. We observed robust production of STAT-3 (the transcription factors), IL-1ß, IL-6 and IL-17 in cecal intraepithelial lymphocytes during the early infection, peaking at 6h p.i. and declining thereafter. The expression of TGF-ß was moderately upregulated and had 2 peaks at 6 and 72h p.i. during the early infection. To further investigate the role of chIL-17 during the infection, we treated the infected chickens with IL-17 and its neutralized antibody. As a result, the reduced fecal oocyst shedding and cecal lesion scores, but enhanced body weight gains were observed in IL-17 neutralized chickens. The results of histopathology showed that the neutrophils recruitment diminished and the parasite burden in IL-17 neutralized chickens decreased. These results may be due to the significant decrease in the production of IL-17, IL-6 and TGF-ß, but enhanced IL-12 and IFN-γ expression in IL-17 neutralized chickens. The converse results were shown in IL-17 treated infected-chickens in which chickens showed increased fecal oocyst shedding, exacerbated lesion scores, and reduced body weight gains. These results suggested that chicken IL-17 might mediate E. tenella - induced immunopathology during the infection.