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1.
Adv Sci (Weinh) ; : e2402025, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38976572

RESUMO

As a significant infectious disease in livestock, porcine reproductive and respiratory syndrome (PRRS) imposes substantial economic losses on the swine industry. Identification of diagnostic markers and therapeutic targets has been a focal challenge in PPRS prevention and control. By integrating metabolomic and lipidomic serum analyses of clinical pig cohorts through a machine learning approach with in vivo and in vitro infection models, lysophosphatidic acid (LPA) is discovered as a serum metabolic biomarker for PRRS virus (PRRSV) clinical diagnosis. PRRSV promoted LPA synthesis by upregulating the autotaxin expression, which causes innate immunosuppression by dampening the retinoic acid-inducible gene I (RIG-I) and type I interferon responses, leading to enhanced virus replication. Targeting LPA demonstrated protection against virus infection and associated disease outcomes in infected pigs, indicating that LPA is a novel antiviral target against PRRSV. This study lays a foundation for clinical prevention and control of PRRSV infections.

2.
J Virol ; 98(5): e0011624, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38591880

RESUMO

Flaviviruses in the Japanese encephalitis virus (JEV) serogroup, such as JEV, West Nile virus, and St. Louis encephalitis virus, can cause severe neurological diseases. The nonstructural protein 1 (NS1) is a multifunctional protein of flavivirus that can be secreted by infected cells and circulate in the host bloodstream. NS1' is an additional form of NS1 protein with 52 amino acids extension at its carboxy-terminal and is produced exclusively by flaviviruses in the JEV serogroup. In this study, we demonstrated that the secreted form of both NS1 and NS1' can disrupt the blood-brain barrier (BBB) of mice, with NS1' exhibiting a stronger effect. Using the in vitro BBB model, we found that treatment of soluble recombinant JEV NS1 or NS1' protein increases the permeability of human brain microvascular endothelial cells (hBMECs) and leads to the degradation of tight junction proteins through the autophagy-lysosomal pathway. Consistently, NS1' protein exhibited a more pronounced effect compared to NS1 in these cellular processes. Further research revealed that the increased expression of macrophage migration inhibitory factor (MIF) is responsible for triggering autophagy after NS1 or NS1' treatment in hBMECs. In addition, TLR4 and NF-κB signaling was found to be involved in the activation of MIF transcription. Moreover, administering the MIF inhibitor has been shown to decrease viral loads and mitigate inflammation in the brains of mice infected with JEV. This research offers a novel perspective on the pathogenesis of JEV. In addition, the stronger effect of NS1' on disrupting the BBB compared to NS1 enhances our understanding of the mechanism by which flaviviruses in the JEV serogroup exhibit neurotropism.IMPORTANCEJapanese encephalitis (JE) is a significant viral encephalitis worldwide, caused by the JE virus (JEV). In some patients, the virus cannot be cleared in time, leading to the breach of the blood-brain barrier (BBB) and invasion of the central nervous system. This invasion may result in cognitive impairment, behavioral disturbances, and even death in both humans and animals. However, the mechanism by which JEV crosses the BBB remains unclear. Previous studies have shown that the flavivirus NS1 protein plays an important role in causing endothelial dysfunction. The NS1' protein is an elongated form of NS1 protein that is particularly produced by flaviviruses in the JEV serogroup. This study revealed that both the secreted NS1 and NS1' of JEV can disrupt the BBB by breaking down tight junction proteins through the autophagy-lysosomal pathway, and NS1' is found to have a stronger effect compared to NS1 in this process. In addition, JEV NS1 and NS1' can stimulate the expression of MIF, which triggers autophagy via the ERK signaling pathway, leading to damage to BBB. Our findings reveal a new function of JEV NS1 and NS1' in the disruption of BBB, thereby providing the potential therapeutic target for JE.


Assuntos
Autofagia , Barreira Hematoencefálica , Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Proteínas não Estruturais Virais , Animais , Humanos , Camundongos , Barreira Hematoencefálica/virologia , Barreira Hematoencefálica/metabolismo , Encéfalo/virologia , Encéfalo/metabolismo , Vírus da Encefalite Japonesa (Espécie)/fisiologia , Encefalite Japonesa/virologia , Encefalite Japonesa/metabolismo , Células Endoteliais/virologia , Células Endoteliais/metabolismo , Fatores Inibidores da Migração de Macrófagos/metabolismo , NF-kappa B/metabolismo , Proteínas não Estruturais Virais/metabolismo
3.
J Neuroinflammation ; 21(1): 76, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532383

RESUMO

Japanese encephalitis virus (JEV) is a neurotropic pathogen that causes lethal encephalitis. The high susceptibility and massive proliferation of JEV in neurons lead to extensive neuronal damage and inflammation within the central nervous system. Despite extensive research on JEV pathogenesis, the effect of JEV on the cellular composition and viral tropism towards distinct neuronal subtypes in the brain is still not well comprehended. To address these issues, we performed single-cell RNA sequencing (scRNA-seq) on cells isolated from the JEV-highly infected regions of mouse brain. We obtained 88,000 single cells and identified 34 clusters representing 10 major cell types. The scRNA-seq results revealed an increasing amount of activated microglia cells and infiltrating immune cells, including monocytes & macrophages, T cells, and natural killer cells, which were associated with the severity of symptoms. Additionally, we observed enhanced communication between individual cells and significant ligand-receptor pairs related to tight junctions, chemokines and antigen-presenting molecules upon JEV infection, suggesting an upregulation of endothelial permeability, inflammation and antiviral response. Moreover, we identified that Baiap2-positive neurons were highly susceptible to JEV. Our findings provide valuable clues for understanding the mechanism of JEV induced neuro-damage and inflammation as well as developing therapies for Japanese encephalitis.


Assuntos
Vírus da Encefalite Japonesa (Espécie) , Vírus da Encefalite Japonesa (Subgrupo) , Encefalite Japonesa , Camundongos , Animais , Tropismo Viral , Sistema Nervoso Central/patologia , Encefalite Japonesa/patologia , Inflamação , Análise de Sequência de RNA
4.
Virol Sin ; 39(1): 144-155, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38104890

RESUMO

Ferroptosis is a newly discovered prototype of programmed cell death (PCD) driven by iron-dependent phospholipid peroxidation â€‹accumulation, and it has been linked to numerous organ injuries and degenerative pathologies. Although studies have shown that a variety of cell death processes contribute to JEV-induced neuroinflammation and neuronal injury, there is currently limited research on the specific involvement of ferroptosis. In this study, we explored the neuronal ferroptosis induced by JEV infection in vitro and in vivo. Our results indicated that JEV infection induces neuronal ferroptosis through inhibiting the function of the antioxidant system mediated by glutathione (GSH)/glutathione peroxidase 4 (GPX4), as well as by promoting lipid peroxidation mediated by yes-associated protein 1 (YAP1)/long-chain acyl-CoA synthetase 4 (ACSL4). Further analyses revealed that JEV E and prM proteins function as agonists, inducing ferroptosis. Moreover, we found that treatment with a ferroptosis inhibitor in JEV-infected mice reduces the viral titers and inflammation in the mouse brains, ultimately improving the survival rate of infected mice. In conclusion, our study unveils a critical role of ferroptosis in the pathogenesis of JEV, providing new ideas for the prevention and treatment of viral encephalitis.


Assuntos
Encefalite Japonesa , Ferroptose , Camundongos , Animais , Doenças Neuroinflamatórias , Neurônios/metabolismo , Apoptose
5.
Infect Med (Beijing) ; 2(3): 212-223, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38073882

RESUMO

Background: West Nile virus is a severe zoonotic pathogen that can cause severe central nervous system symptoms in humans and horses, and is fatal for birds, chickens and other poultry. With no specific drugs or vaccines available, antibody-based therapy is a promising treatment. This study aims to develop neutralizing antibodies against West Nile virus and assess their cross-protective potential against Japanese encephalitis virus. Methods: Monoclonal antibodies against WNV and JEV were isolated by hybridoma technology. The therapeutic efficacy of these antibodies was evaluated using a mouse model, and a humanized version of the monoclonal antibody was generated for potential human application. Results: In this study, we generated eight monoclonal antibodies that exhibit neutralizing activity against WNV. Their therapeutic effects against WNV were validated both in vivo and in vitro. Among these antibodies, C9-G11-F3 also exhibited cross-protective activity against JEV. We also humanized the antibody to ensure that it could be used for WNV infection treatment in humans. Conclusion: This study highlights the importance of neutralizing antibodies as a promising approach for protection against West Nile virus infection and suggests their potential utility in the development of therapeutic interventions.

6.
iScience ; 26(7): 107197, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37456831

RESUMO

Alveolar macrophages (AMs) are resident innate immune cells that play vital roles in maintaining lung physiological functions. However, the effects of aging on their dynamics, heterogeneity, and transcriptional profiles remain to be fully elucidated. Through single cell RNA sequencing (scRNA-seq), we identified CBFß as an indispensable transcription factor that ensures AM self-renewal. Intriguingly, despite transcriptome similarities of proliferating cells, AMs from aged mice exhibited reduced embryonic stem cell-like features. Aged AMs also displayed compromised DNA repair abilities, potentially leading to obstructed cell cycle progression and an elevation of senescence markers. Consistently, AMs from aged mice exhibited impaired self-renewal ability and reduced sensitivity to GM-CSF. Decreased CBFß was observed in the cytosol of AMs from aged mice. Similar senescence-like phenotypes were also found in human AMs. Taken together, these findings suggest that AMs in aged hosts demonstrate senescence-like phenotypes, potentially facilitated by the abrogated CBF ß activity.

7.
Sci Immunol ; 8(82): eadf0348, 2023 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-36821695

RESUMO

The relationship between diabetes and coronavirus disease 2019 (COVID-19) is bidirectional: Although individuals with diabetes and high blood glucose (hyperglycemia) are predisposed to severe COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can also cause hyperglycemia and exacerbate underlying metabolic syndrome. Therefore, interventions capable of breaking the network of SARS-CoV-2 infection, hyperglycemia, and hyperinflammation, all factors that drive COVID-19 pathophysiology, are urgently needed. Here, we show that genetic ablation or pharmacological inhibition of mitochondrial pyruvate carrier (MPC) attenuates severe disease after influenza or SARS-CoV-2 pneumonia. MPC inhibition using a second-generation insulin sensitizer, MSDC-0602K (MSDC), dampened pulmonary inflammation and promoted lung recovery while concurrently reducing blood glucose levels and hyperlipidemia after viral pneumonia in obese mice. Mechanistically, MPC inhibition enhanced mitochondrial fitness and destabilized hypoxia-inducible factor-1α, leading to dampened virus-induced inflammatory responses in both murine and human lung macrophages. We further showed that MSDC enhanced responses to nirmatrelvir (the antiviral component of Paxlovid) to provide high levels of protection against severe host disease development after SARS-CoV-2 infection and suppressed cellular inflammation in human COVID-19 lung autopsies, demonstrating its translational potential for treating severe COVID-19. Collectively, we uncover a metabolic pathway that simultaneously modulates pulmonary inflammation, tissue recovery, and host metabolic health, presenting a synergistic therapeutic strategy to treat severe COVID-19, particularly in patients with underlying metabolic disease.


Assuntos
COVID-19 , Diabetes Mellitus , Hiperglicemia , Humanos , Animais , Camundongos , Transportadores de Ácidos Monocarboxílicos , SARS-CoV-2/metabolismo , Glicemia/metabolismo , Hiperglicemia/tratamento farmacológico , Hiperglicemia/metabolismo
8.
Annu Rev Immunol ; 41: 277-300, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-36716750

RESUMO

Emerging and re-emerging respiratory viral infections pose a tremendous threat to human society, as exemplified by the ongoing COVID-19 pandemic. Upon viral invasion of the respiratory tract, the host initiates coordinated innate and adaptive immune responses to defend against the virus and to promote repair of the damaged tissue. However, dysregulated host immunity can also cause acute morbidity, hamper lung regeneration, and/or lead to chronic tissue sequelae. Here, we review our current knowledge of the immune mechanisms regulating antiviral protection, host pathogenesis, inflammation resolution, and lung regeneration following respiratory viral infections, mainly using influenza virus and SARS-CoV-2 infections as examples. We hope that this review sheds light on future research directions to elucidate the cellular and molecular cross talk regulating host recovery and to pave the way to the development of pro-repair therapeutics to augment lung regeneration following viral injury.


Assuntos
COVID-19 , Humanos , Animais , Imunidade Inata , Pandemias , SARS-CoV-2 , Inflamação/patologia
9.
J Immunol ; 208(6): 1456-1466, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35165165

RESUMO

Alveolar macrophages (AMs) are major lung tissue-resident macrophages capable of proliferating and self-renewal in situ. AMs are vital in pulmonary antimicrobial immunity and surfactant clearance. The mechanisms regulating AM compartment formation and maintenance remain to be fully elucidated currently. In this study, we have explored the roles of mitochondrial transcription factor A (TFAM)-mediated mitochondrial fitness and metabolism in regulating AM formation and function. We found that TFAM deficiency in mice resulted in significantly reduced AM numbers and impaired AM maturation in vivo. TFAM deficiency was not required for the generation of AM precursors nor the differentiation of AM precursors into AMs, but was critical for the maintenance of AM compartment. Mechanistically, TFAM deficiency diminished gene programs associated with AM proliferation and self-renewal and promoted the expression of inflammatory genes in AMs. We further showed that TFAM-mediated AM compartment impairment resulted in defective clearance of cellular debris and surfactant in the lung and increased the host susceptibility to severe influenza virus infection. Finally, we found that influenza virus infection in AMs led to impaired TFAM expression and diminished mitochondrial fitness and metabolism. Thus, our data have established the critical function of TFAM-mediated mitochondrial metabolism in AM maintenance and function.


Assuntos
Influenza Humana , Infecções por Orthomyxoviridae , Animais , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Grupo de Alta Mobilidade/genética , Proteínas de Grupo de Alta Mobilidade/metabolismo , Homeostase/genética , Humanos , Pulmão , Macrófagos Alveolares , Camundongos , Camundongos Knockout , Infecções por Orthomyxoviridae/metabolismo , Tensoativos/metabolismo
10.
Immunity ; 54(6): 1200-1218.e9, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-33951416

RESUMO

Tissue macrophages self-renew during homeostasis and produce inflammatory mediators upon microbial infection. We examined the relationship between proliferative and inflammatory properties of tissue macrophages by defining the impact of the Wnt/ß-catenin pathway, a central regulator of self-renewal, in alveolar macrophages (AMs). Activation of ß-catenin by Wnt ligand inhibited AM proliferation and stemness, but promoted inflammatory activity. In a murine influenza viral pneumonia model, ß-catenin-mediated AM inflammatory activity promoted acute host morbidity; in contrast, AM proliferation enabled repopulation of reparative AMs and tissue recovery following viral clearance. Mechanistically, Wnt treatment promoted ß-catenin-HIF-1α interaction and glycolysis-dependent inflammation while suppressing mitochondrial metabolism and thereby, AM proliferation. Differential HIF-1α activities distinguished proliferative and inflammatory AMs in vivo. This ß-catenin-HIF-1α axis was conserved in human AMs and enhanced HIF-1α expression associated with macrophage inflammation in COVID-19 patients. Thus, inflammatory and reparative activities of lung macrophages are regulated by ß-catenin-HIF-1α signaling, with implications for the treatment of severe respiratory diseases.


Assuntos
COVID-19/imunologia , COVID-19/virologia , Autorrenovação Celular/imunologia , Interações Hospedeiro-Patógeno/imunologia , Macrófagos/imunologia , SARS-CoV-2/imunologia , Biomarcadores , COVID-19/metabolismo , Citocinas/metabolismo , Suscetibilidade a Doenças/imunologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Mediadores da Inflamação/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/metabolismo , Transdução de Sinais
11.
Nat Commun ; 12(1): 2187, 2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33846346

RESUMO

The RNA-sensing pathway contributes to type I interferon (IFN) production induced by DNA damaging agents. However, the potential involvement of RNA sensors in DNA repair is unknown. Here, we found that retinoic acid-inducible gene I (RIG-I), a key cytosolic RNA sensor that recognizes RNA virus and initiates the MAVS-IRF3-type I IFN signaling cascade, is recruited to double-stranded breaks (DSBs) and suppresses non-homologous end joining (NHEJ). Mechanistically, RIG-I interacts with XRCC4, and the RIG-I/XRCC4 interaction impedes the formation of XRCC4/LIG4/XLF complex at DSBs. High expression of RIG-I compromises DNA repair and sensitizes cancer cells to irradiation treatment. In contrast, depletion of RIG-I renders cells resistant to irradiation in vitro and in vivo. In addition, this mechanism suggests a protective role of RIG-I in hindering retrovirus integration into the host genome by suppressing the NHEJ pathway. Reciprocally, XRCC4, while suppressed for its DNA repair function, has a critical role in RIG-I immune signaling through RIG-I interaction. XRCC4 promotes RIG-I signaling by enhancing oligomerization and ubiquitination of RIG-I, thereby suppressing RNA virus replication in host cells. In vivo, silencing XRCC4 in mouse lung promotes influenza virus replication in mice and these mice display faster body weight loss, poorer survival, and a greater degree of lung injury caused by influenza virus infection. This reciprocal regulation of RIG-I and XRCC4 reveals a new function of RIG-I in suppressing DNA repair and virus integration into the host genome, and meanwhile endues XRCC4 with a crucial role in potentiating innate immune response, thereby helping host to prevail in the battle against virus.


Assuntos
Proteína DEAD-box 58/metabolismo , Reparo do DNA , Proteínas de Ligação a DNA/metabolismo , Receptores Imunológicos/metabolismo , Transdução de Sinais/imunologia , Células A549 , Animais , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Reparo do DNA por Junção de Extremidades/efeitos da radiação , Reparo do DNA/efeitos da radiação , Relação Dose-Resposta à Radiação , Genoma Humano , Células HEK293 , Humanos , Camundongos , Radiação Ionizante , Retroviridae/metabolismo , Replicação Viral/efeitos da radiação
13.
Sci Immunol ; 5(53)2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-33158975

RESUMO

Lower respiratory viral infections, such as influenza virus and severe acute respiratory syndrome coronavirus 2 infections, often cause severe viral pneumonia in aged individuals. Here, we report that influenza viral pneumonia leads to chronic nonresolving lung pathology and exacerbated accumulation of CD8+ tissue-resident memory T cells (TRM) in the respiratory tract of aged hosts. TRM cell accumulation relies on elevated TGF-ß present in aged tissues. Further, we show that TRM cells isolated from aged lungs lack a subpopulation characterized by expression of molecules involved in TCR signaling and effector function. Consequently, TRM cells from aged lungs were insufficient to provide heterologous protective immunity. The depletion of CD8+ TRM cells dampens persistent chronic lung inflammation and ameliorates tissue fibrosis in aged, but not young, animals. Collectively, our data demonstrate that age-associated TRM cell malfunction supports chronic lung inflammatory and fibrotic sequelae after viral pneumonia.


Assuntos
Linfócitos T CD8-Positivos/imunologia , COVID-19/imunologia , Memória Imunológica/imunologia , Pulmão/imunologia , Pneumonia Viral/imunologia , SARS-CoV-2/imunologia , Fatores Etários , Animais , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/virologia , COVID-19/metabolismo , COVID-19/virologia , Interações Hospedeiro-Patógeno/imunologia , Humanos , Influenza Humana/imunologia , Influenza Humana/metabolismo , Influenza Humana/virologia , Pulmão/metabolismo , Pulmão/virologia , Camundongos Endogâmicos C57BL , Orthomyxoviridae/imunologia , Orthomyxoviridae/fisiologia , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/virologia , Pandemias , Pneumonia Viral/metabolismo , Pneumonia Viral/virologia , SARS-CoV-2/fisiologia , Fator de Crescimento Transformador beta/imunologia , Fator de Crescimento Transformador beta/metabolismo
15.
Front Immunol ; 10: 2332, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31681267

RESUMO

Tissue resident memory CD8 T cells (TRM) serve as potent local sentinels and contribute significantly to protective immunity against intracellular mucosal pathogens. While the molecular and transcriptional underpinnings of TRM differentiation are emerging, how TRM establishment is regulated by other leukocytes in vivo is largely unclear. Here, we observed that expression of PPAR-γ in the myeloid compartment was a negative regulator of CD8 TRM establishment following influenza virus infection. Interestingly, myeloid deficiency of PPAR-γ resulted in selective impairment of the tissue-resident alveolar macrophage (AM) compartment during primary influenza infection, suggesting that AM are likely negative regulators of CD8 TRM differentiation. Indeed, influenza-specific CD8 TRM cell numbers were increased following early, but not late ablation of AM using the CD169-DTR model. Importantly, these findings were specific to the parenchyma of infected tissue as circulating memory T cell frequencies in lung and TCM and TEM in spleen were largely unaltered following macrophage ablation. Further, the magnitude of the effector response could not explain these observations. These data indicate local regulation of pulmonary TRM differentiation is alveolar macrophage dependent. These, findings could aid in vaccine design aimed at increasing TRM density to enhance protective immunity, or deflating their numbers in conditions where they cause overt or veiled chronic pathologies.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Memória Imunológica , Vírus da Influenza A/imunologia , Pulmão/imunologia , Macrófagos Alveolares/imunologia , Infecções por Orthomyxoviridae/imunologia , Animais , Linfócitos T CD8-Positivos/patologia , Linfócitos T CD8-Positivos/virologia , Pulmão/patologia , Pulmão/virologia , Macrófagos Alveolares/patologia , Macrófagos Alveolares/virologia , Camundongos , Camundongos Transgênicos , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/patologia , PPAR gama/genética , PPAR gama/imunologia
16.
PLoS One ; 14(10): e0223430, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31584978

RESUMO

Influenza virus causes a heterogeneous respiratory infectious disease ranging from self-limiting symptoms to non-resolving pathology in the lungs. Worldwide, seasonal influenza infections claim ~500,000 lives annually. Recent reports describe pathologic pulmonary sequelae that result in remodeling the architecture of lung parenchyma following respiratory infections. These dysfunctional recovery processes that disproportionately impact the elderly have been understudied. Macrophages are involved in tissue remodeling and are critical for survival of severe influenza infection. Here, we found intrinsic deficiency of the nuclear receptor PPAR-γ in myeloid cells delayed the resolution of pulmonary inflammation following influenza infection. Mice with myeloid cell-specific PPAR-γ deficiency subsequently presented with increased influenza-induced deposition of pulmonary collagen compared to control mice. This dysfunctional lung remodeling was progressive and sustained for at least 3 months following infection of mice with myeloid PPAR-γ deficiency. These progressive changes were accompanied by a pro-fibrotic gene signature from lung macrophages and preceded by deficiencies in activation of genes involved with damage repair. Importantly similar aberrant gene expression patterns were also found in a secondary analysis of a study where macrophages were isolated from patients with fibrotic interstitial lung disease. Quite unexpectedly, mice with PPAR-γ deficient macrophages were more resistant to bleomycin-induced weight loss whereas extracellular matrix deposition was unaffected compared to controls. Therefore PPAR-γ expression in macrophages may be a pathogen-specific limiter of organ recovery rather than a ubiquitous effector pathway in response to generic damage.


Assuntos
Vírus da Influenza A , Macrófagos Alveolares/metabolismo , Infecções por Orthomyxoviridae/complicações , PPAR gama/metabolismo , Fibrose Pulmonar/etiologia , Fibrose Pulmonar/metabolismo , Animais , Biomarcadores , Bleomicina/efeitos adversos , Colágeno/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças , Expressão Gênica , Mediadores da Inflamação/metabolismo , Macrófagos Alveolares/imunologia , Camundongos , Camundongos Transgênicos , Células Mieloides/imunologia , Células Mieloides/metabolismo , Infecções por Orthomyxoviridae/virologia , PPAR gama/deficiência , PPAR gama/genética , Pneumonia/complicações , Pneumonia/etiologia , Pneumonia/patologia , Fibrose Pulmonar/patologia
17.
Immunity ; 51(3): 491-507.e7, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31533057

RESUMO

Tissue-resident memory CD8+ T (Trm) cells share core residency gene programs with tumor-infiltrating lymphocytes (TILs). However, the transcriptional, metabolic, and epigenetic regulation of Trm cell and TIL development and function is largely undefined. Here, we found that the transcription factor Bhlhe40 was specifically required for Trm cell and TIL development and polyfunctionality. Local PD-1 signaling inhibited TIL Bhlhe40 expression, and Bhlhe40 was critical for TIL reinvigoration following anti-PD-L1 blockade. Mechanistically, Bhlhe40 sustained Trm cell and TIL mitochondrial fitness and a functional epigenetic state. Building on these findings, we identified an epigenetic and metabolic regimen that promoted Trm cell and TIL gene signatures associated with tissue residency and polyfunctionality. This regimen empowered the anti-tumor activity of CD8+ T cells and possessed therapeutic potential even at an advanced tumor stage in mouse models. Our results provide mechanistic insights into the local regulation of Trm cell and TIL function.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/imunologia , Linfócitos T CD8-Positivos/imunologia , Proteínas de Homeodomínio/imunologia , Mitocôndrias/imunologia , Animais , Epigênese Genética/imunologia , Regulação da Expressão Gênica/imunologia , Linfócitos do Interstício Tumoral/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Receptor de Morte Celular Programada 1/imunologia
18.
Proc Natl Acad Sci U S A ; 116(24): 11888-11893, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31138703

RESUMO

Neutrophils are vital for antimicrobial defense; however, their role during viral infection is less clear. Furthermore, the molecular regulation of neutrophil fate and function at the viral infected sites is largely elusive. Here we report that BCL6 deficiency in myeloid cells exhibited drastically enhanced host resistance to severe influenza A virus (IAV) infection. In contrast to the notion that BCL6 functions to suppress innate inflammation, we find that myeloid BCL6 deficiency diminished lung inflammation without affecting viral loads. Using a series of Cre-transgenic, reporter, and knockout mouse lines, we demonstrate that BCL6 deficiency in neutrophils, but not in monocytes or lung macrophages, attenuated host inflammation and morbidity following IAV infection. Mechanistically, BCL6 bound to the neutrophil gene loci involved in cellular apoptosis in cells specifically at the site of infection. As such, BCL6 disruption resulted in increased expression of apoptotic genes in neutrophils in the respiratory tract, but not in the circulation or bone marrow. Consequently, BCL6 deficiency promoted tissue neutrophil apoptosis. Partial neutrophil depletion led to diminished pulmonary inflammation and decreased host morbidity. Our results reveal a previously unappreciated role of BCL6 in modulating neutrophil apoptosis at the site of infection for the regulation of host disease development following viral infection. Furthermore, our studies indicate that tissue-specific regulation of neutrophil survival modulates host inflammation and tissue immunopathology during acute respiratory viral infection.


Assuntos
Vírus da Influenza A/patogenicidade , Neutrófilos/metabolismo , Infecções por Orthomyxoviridae/metabolismo , Pneumonia/metabolismo , Proteínas Proto-Oncogênicas c-bcl-6/metabolismo , Animais , Apoptose/fisiologia , Interações Hospedeiro-Patógeno/fisiologia , Pulmão/metabolismo , Pulmão/virologia , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/virologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infiltração de Neutrófilos/fisiologia , Neutrófilos/virologia , Pneumonia/virologia , Infecções Respiratórias/metabolismo , Infecções Respiratórias/virologia
19.
J Virol ; 93(9)2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30787149

RESUMO

Alveolar macrophages (AM) play pivotal roles in modulating host defense, pulmonary inflammation, and tissue injury following respiratory viral infections. However, the transcriptional regulation of AM function during respiratory viral infections is still largely undefined. Here we have screened the expression of 84 transcription factors in AM in response to influenza A virus (IAV) infection. We found that the transcription factor PPAR-γ was downregulated following IAV infection in AM through type I interferon (IFN)-dependent signaling. PPAR-γ expression in AM was critical for the suppression of exaggerated antiviral and inflammatory responses of AM following IAV and respiratory syncytial virus (RSV) infections. Myeloid PPAR-γ deficiency resulted in enhanced host morbidity and increased pulmonary inflammation following both IAV and RSV infections, suggesting that macrophage PPAR-γ is vital for restricting severe host disease development. Using approaches to selectively deplete recruiting monocytes, we demonstrate that PPAR-γ expression in resident AM is likely important in regulating host disease development. Furthermore, we show that PPAR-γ was critical for the expression of wound healing genes in AM. As such, myeloid PPAR-γ deficiency resulted in impaired inflammation resolution and defective tissue repair following IAV infection. Our data suggest a critical role of PPAR-γ expression in lung macrophages in the modulation of pulmonary inflammation, the development of acute host diseases, and the proper restoration of tissue homeostasis following respiratory viral infections.IMPORTANCE Respiratory viral infections, like IAV and respiratory syncytial virus (RSV) infections, impose great challenges to public health. Alveolar macrophages (AM) are lung-resident immune cells that play important roles in protecting the host against IAV and RSV infections. However, the underlying molecular mechanisms by which AM modulate host inflammation, disease development, and tissue recovery are not very well understood. Here we identify that PPAR-γ expression in AM is crucial to suppress pulmonary inflammation and diseases and to promote fast host recovery from IAV and RSV infections. Our data suggest that targeting macrophage PPAR-γ may be a promising therapeutic option in the future to suppress acute inflammation and simultaneously promote recovery from severe diseases associated with respiratory viral infections.


Assuntos
Vírus da Influenza A/metabolismo , Macrófagos Alveolares/metabolismo , Infecções por Orthomyxoviridae/metabolismo , PPAR gama/biossíntese , Pneumonia Viral/metabolismo , Infecções por Vírus Respiratório Sincicial/metabolismo , Vírus Sinciciais Respiratórios/metabolismo , Animais , Regulação da Expressão Gênica , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Inflamação/virologia , Macrófagos Alveolares/patologia , Macrófagos Alveolares/virologia , Camundongos , Camundongos Knockout , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/patologia , PPAR gama/genética , Pneumonia Viral/genética , Pneumonia Viral/patologia , Infecções por Vírus Respiratório Sincicial/genética , Infecções por Vírus Respiratório Sincicial/patologia
20.
Front Immunol ; 8: 1237, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29033949

RESUMO

Japanese encephalitis virus (JEV) is the leading cause of epidemic encephalitis worldwide. JEV-induced neuroinflammation is characterized by profound neuronal cells damage accompanied by activation of glial cells. Albeit long non-coding RNAs (lncRNAs) have been emerged as important regulatory RNAs with profound effects on various biological processes, it is unknown how lncRNAs regulate JEV-induced inflammation. Here, using microarray approach, we identified 618 lncRNAs and 1,007 mRNAs differentially expressed in JEV-infected mice brain. The functional annotation analysis revealed that differentially regulated transcripts were predominantly involved in various signaling pathways related to host immune and inflammatory responses. The lncRNAs with their potential to regulate JEV-induced inflammatory response were identified by constructing the lncRNA-mRNA coexpression network. Furthermore, silencing of the two selected lncRNAs (E52329 and N54010) resulted in reducing the phosphorylation of JNK and MKK4, which are known to be involved during inflammatory response. Collectively, we first demonstrated the transcriptomic landscape of lncRNAs in mice brain infected with JEV and analyzed the coexpression network of differentially regulated lncRNAs and mRNAs during JEV infection. Our results provide a better understanding of the host response to JEV infection and suggest that the identified lncRNAs may be used as potential therapeutic targets for the management of Japanese encephalitis.

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