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1.
Proc Natl Acad Sci U S A ; 119(1)2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34969857

RESUMO

Type I interferons (IFNs) are the first frontline of the host innate immune response against invading pathogens. Herein, we characterized an unknown protein encoded by phospholipase A2 inhibitor and LY6/PLAUR domain-containing (PINLYP) gene that interacted with TBK1 and induced type I IFN in a TBK1- and IRF3-dependent manner. Loss of PINLYP impaired the activation of IRF3 and production of IFN-ß induced by DNA virus, RNA virus, and various Toll-like receptor ligands in multiple cell types. Because PINLYP deficiency in mice engendered an early embryonic lethality in mice, we generated a conditional mouse in which PINLYP was depleted in dendritic cells. Mice lacking PINLYP in dendritic cells were defective in type I IFN induction and more susceptible to lethal virus infection. Thus, PINLYP is a positive regulator of type I IFN innate immunity and important for effective host defense against viral infection.


Assuntos
Células Dendríticas/imunologia , Inibidores Enzimáticos/imunologia , Imunidade Inata , Interferon beta/imunologia , Animais , Linhagem Celular , Infecções por Vírus de DNA/genética , Infecções por Vírus de DNA/imunologia , Vírus de DNA/genética , Vírus de DNA/imunologia , Humanos , Interferon beta/genética , Camundongos , Camundongos Knockout , Infecções por Vírus de RNA/genética , Infecções por Vírus de RNA/imunologia , Vírus de RNA/genética , Vírus de RNA/imunologia
2.
J Med Virol ; 96(2): e29440, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38299675

RESUMO

Post-transplant lymphoproliferative disorders (PTLDs) are associated with Epstein-Barr virus (EBV) infection in transplant recipients. Most of lymphoblastoid cell lines (LCLs) derived from EBV-immortalized B cells or PTLDs are sensitive to CD95-mediated apoptosis and cytotoxic T cell (CTL) killing. CD95 ligand (CD95L) exists as a transmembrane ligand (mCD95L) or a soluble form (sCD95L). Using recombinant mCD95L and sCD95L, we observed that sCD95L does not affect LCLs. While high expression of mCD95L in CTLs promotes apoptosis of LCLs, low expression induces clathrin-dependent CD19 internalization, caspase-dependent CD19 cleavage, and proteasomal/lysosomal-dependent CD19 degradation. The CD95L/CD95-mediated CD19 degradation impairs B cell receptor (BCR) signaling and inhibits BCR-mediated EBV activation. Interestingly, although inhibition of the caspase activity restores CD19 expression and CD19-mediated BCR activation, it fails to rescue BCR-mediated EBV lytic gene expression. EBV-specific CTLs engineered to overexpress mCD95L exhibit a stronger killing activity against LCLs. This study highlights that engineering EBV-specific CTLs to express a higher level of mCD95L could represent an attractive therapeutic approach to improve T cell immunotherapy for PTLDs.


Assuntos
Infecções por Vírus Epstein-Barr , Humanos , Proteína Ligante Fas , Herpesvirus Humano 4/fisiologia , Caspases , Receptores de Antígenos de Linfócitos B/metabolismo
3.
EMBO J ; 38(18): e102075, 2019 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-31390091

RESUMO

RIG-I-MAVS antiviral signaling represents an important pathway to stimulate interferon production and confer innate immunity to the host. Upon binding to viral RNA and Riplet-mediated polyubiquitination, RIG-I promotes prion-like aggregation and activation of MAVS. MAVS subsequently induces interferon production by activating two signaling pathways mediated by TBK1-IRF3 and IKK-NF-κB respectively. However, the mechanism underlying the activation of MAVS downstream pathways remains elusive. Here, we demonstrated that activation of TBK1-IRF3 by MAVS-Region III depends on its multimerization state and identified TRAF3IP3 as a critical regulator for the downstream signaling. In response to virus infection, TRAF3IP3 is accumulated on mitochondria and thereby facilitates the recruitment of TRAF3 to MAVS for TBK1-IRF3 activation. Traf3ip3-deficient mice demonstrated a severely compromised potential to induce interferon production and were vulnerable to RNA virus infection. Our findings uncover that TRAF3IP3 is an important regulator for RIG-I-MAVS signaling, which bridges MAVS and TRAF3 for an effective antiviral innate immune response.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Fator 3 Associado a Receptor de TNF/metabolismo , Viroses/imunologia , Animais , Linhagem Celular , Modelos Animais de Doenças , Células HEK293 , Células HeLa , Humanos , Imunidade Inata , Fator Regulador 3 de Interferon/metabolismo , Camundongos , Mitocôndrias/metabolismo , Multimerização Proteica , Proteínas Serina-Treonina Quinases/metabolismo , Fator 3 Associado a Receptor de TNF/genética , Viroses/genética
4.
Am J Hum Genet ; 107(1): 15-23, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32473092

RESUMO

Normal oocyte meiosis is a prerequisite for successful human reproduction, and abnormalities in the process will result in infertility. In 2016, we identified mutations in TUBB8 as responsible for human oocyte meiotic arrest. However, the underlying genetic factors for most affected individuals remain unknown. TRIP13, encoding an AAA-ATPase, is a key component of the spindle assembly checkpoint, and recurrent homozygous nonsense variants and a splicing variant in TRIP13 are reported to cause Wilms tumors in children. In this study, we identified homozygous and compound heterozygous missense pathogenic variants in TRIP13 responsible for female infertility mainly characterized by oocyte meiotic arrest in five individuals from four independent families. Individuals from three families suffered from oocyte maturation arrest, whereas the individual from the fourth family had abnormal zygote cleavage. All displayed only the infertility phenotype without Wilms tumors or any other abnormalities. In vitro and in vivo studies showed that the identified variants reduced the protein abundance of TRIP13 and caused its downstream molecule, HORMAD2, to accumulate in HeLa cells and in proband-derived lymphoblastoid cells. The chromosome mis-segregation assay showed that variants did not have any effects on mitosis. Injecting TRIP13 cRNA into oocytes from one affected individual was able to rescue the phenotype, which has implications for future therapeutic treatments. This study reports pathogenic variants in TRIP13 responsible for oocyte meiotic arrest, and it highlights the pivotal but different roles of TRIP13 in meiosis and mitosis. These findings also indicate that different dosage effects of mutant TRIP13 might result in two distinct human diseases.


Assuntos
ATPases Associadas a Diversas Atividades Celulares/genética , Proteínas de Ciclo Celular/genética , Infertilidade Feminina/genética , Mutação de Sentido Incorreto/genética , Oócitos/patologia , Adulto , Alelos , Linhagem Celular Tumoral , Feminino , Células HeLa , Homozigoto , Humanos , Meiose/genética , Fenótipo , Zigoto/patologia
5.
PLoS Pathog ; 16(7): e1008701, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32735617

RESUMO

Gammaherpesviruses have evolved various strategies to take advantage of host cellular factors or signaling pathways to establish a lifelong latent infection. Like the human gammaherpesvirus Epstein-Barr virus, murine gammaherpesvirus 68 (MHV68) establishes and maintains latency in the memory B cells during infection of laboratory mice. We have previously shown that MHV68 can immortalize fetal liver-derived B cells that induce lymphomas when injected into immunodeficient mice. Here we identify interleukin 16 (IL16) as a most abundantly expressed cytokine in MHV68-immortalized B cells and show that MHV68 infection elevates IL16 expression. IL16 is not important for MHV68 lytic infection but plays a critical role in MHV68 reactivation from latency. IL16 deficiency increases MHV68 lytic gene expression in MHV68-immortalized B cells and enhances reactivation from splenic latency. Correlatively, IL16 deficiency increases the frequency of MHV68-infected plasma cells that can be attributed to enhanced MHV68 reactivation. Furthermore, similar to TPA-mediated lytic replication of Kaposi's sarcoma-associated herpesvirus, IL16 deficiency markedly induces Tyr705 STAT3 de-phosphorylation and elevates p21 expression, which can be counteracted by the tyrosine phosphatase inhibitor orthovanadate. Importantly, orthovanadate strongly blocks MHV68 lytic gene expression mediated by IL16 deficiency. These data demonstrate that virus-induced IL16 does not directly participate in MHV68 lytic replication, but rather inhibits virus reactivation to facilitate latent infection, in part through the STAT3-p21 axis.


Assuntos
Infecções por Herpesviridae/metabolismo , Interleucina-16/metabolismo , Infecções Tumorais por Vírus/metabolismo , Ativação Viral/fisiologia , Latência Viral/fisiologia , Animais , Linfócitos B/virologia , Infecções por Herpesviridae/imunologia , Interleucina-16/imunologia , Linfoma/virologia , Camundongos , Rhadinovirus/imunologia , Rhadinovirus/metabolismo
6.
PLoS Pathog ; 15(2): e1007628, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30811506

RESUMO

Kaposi's sarcoma-associated herpesvirus (KSHV) latently infects host cells and establishes lifelong persistence as an extra-chromosomal episome in the nucleus. To persist in proliferating cells, the viral genome typically replicates once per cell cycle and is distributed into daughter cells. This process involves host machinery utilized by KSHV, however the underlying mechanisms are not fully elucidated. In present study, we found that N-Myc downstream regulated gene 1 (NDRG1), a cellular gene known to be non-detectable in primary B cells and endothelial cells which are the major cell types for KSHV infection in vivo, was highly upregulated by KSHV in these cells. We further demonstrated that the high expression of NDRG1 was regulated by latency-associated nuclear antigen (LANA), the major viral latent protein which tethers the viral genome to host chromosome and plays an essential role in viral genome maintenance. Surprisingly, knockdown of NDRG1 in KSHV latently infected cells resulted in a significant decrease of viral genome copy number in these cells. Interestingly, NDRG1 can directly interact with proliferating cell nuclear antigen (PCNA), a cellular protein which functions as a DNA polymerase clamp during DNA replication. Intriguingly, we found that NDRG1 forms a complex with LANA and PCNA and serves as a scaffold protein bridging these two proteins. We further demonstrated that NDRG1 is critical for mediating LANA to recruit PCNA onto terminal repeat (TR) of KSHV genome, and facilitates viral DNA replication and episome persistence. Taken together, our findings suggest that NDRG1 plays an important role in KSHV viral genome replication, and provide new clues for understanding of KSHV persistence.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Herpesvirus Humano 8/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Adulto , Antígenos Virais/metabolismo , Proteínas de Ciclo Celular/genética , Linhagem Celular , Núcleo Celular/metabolismo , Replicação do DNA , DNA Viral/genética , DNA Polimerase Dirigida por DNA/metabolismo , Genoma Viral , Células HEK293 , Infecções por Herpesviridae/metabolismo , Infecções por Herpesviridae/virologia , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Proteínas Nucleares/metabolismo , Plasmídeos/genética , Sarcoma de Kaposi/metabolismo , Sarcoma de Kaposi/virologia , Regulação para Cima , Latência Viral , Replicação Viral
7.
J Biol Chem ; 293(8): 2801-2814, 2018 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-29305424

RESUMO

The stress-induced unfolded protein response (UPR) in the endoplasmic reticulum (ER) involves various signaling cross-talks and controls cell fate. B-cell receptor (BCR) signaling, which can trigger UPR, induces gammaherpesvirus lytic replication and serves as a physiological mechanism for gammaherpesvirus reactivation in vivo However, how the UPR regulates BCR-mediated gammaherpesvirus infection is unknown. Here, we demonstrate that the ER stressors tunicamycin and thapsigargin inhibit BCR-mediated murine gammaherpesvirus 68 (MHV68) lytic replication by inducing expression of the UPR mediator Bip and blocking activation of Akt, ERK, and JNK. Both Bip and the downstream transcription factor ATF4 inhibited BCR-mediated MHV68 lytic gene expression, whereas UPR-induced C/EBP homologous protein (CHOP) was required for and promoted BCR-mediated MHV68 lytic replication by suppressing upstream Bip and ATF4 expression. Bip knockout was sufficient to rescue BCR-mediated MHV68 lytic gene expression in CHOP knockout cells, and this rescue was blocked by ectopic ATF4 expression. Furthermore, ATF4 directly inhibited promoter activity of the MHV68 lytic switch transactivator RTA. Altogether, we show that ER stress-induced CHOP inhibits Bip and ATF4 expression and that ATF4, in turn, plays a critical role in CHOP-mediated regulation of BCR-controlled MHV68 lytic replication. We conclude that ER stress-mediated UPR and BCR signaling pathways are interconnected and form a complex network to regulate the gammaherpesvirus infection cycle.


Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Linfócitos B/virologia , Estresse do Retículo Endoplasmático , Gammaherpesvirinae/fisiologia , Proteínas de Choque Térmico/metabolismo , Receptores de Antígenos de Linfócitos B/agonistas , Fator de Transcrição CHOP/metabolismo , Fator 4 Ativador da Transcrição/antagonistas & inibidores , Fator 4 Ativador da Transcrição/genética , Animais , Antivirais/farmacologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linhagem Celular Transformada , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Gammaherpesvirinae/efeitos dos fármacos , Gammaherpesvirinae/crescimento & desenvolvimento , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas de Inativação de Genes , Proteínas de Choque Térmico/antagonistas & inibidores , Proteínas de Choque Térmico/genética , Lisogenia/efeitos dos fármacos , Camundongos , Chaperonas Moleculares/antagonistas & inibidores , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Regiões Promotoras Genéticas/efeitos dos fármacos , Receptores de Antígenos de Linfócitos B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tapsigargina/farmacologia , Fator de Transcrição CHOP/antagonistas & inibidores , Fator de Transcrição CHOP/genética , Tunicamicina/farmacologia , Proteínas Virais/antagonistas & inibidores , Proteínas Virais/genética , Proteínas Virais/metabolismo , Ativação Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
8.
J Gen Virol ; 100(5): 851-862, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30907723

RESUMO

Epstein-Barr virus (EBV) establishes a life-long latency in memory B cells, whereas plasma cell differentiation is linked to EBV lytic reactivation from latently infected B cells. EBV lytic replication is mediated by the two immediate-early switch proteins Zta and RTA. Both plasma cell transcription factors XBP-1 and Blimp-1 have been shown to enable the triggering of EBV lytic reactivation by activating the transcription of Zta or RTA. Here we show that interferon regulatory factor 4 (IRF4), another plasma cell transcription factor that is either not expressed or expressed at a low level in EBV-positive Burkitt's lymphoma (BL) cells, can activate the promoters of EBV Zta and RTA, but is not sufficient to elicit EBV lytic reactivation in latently infected BL cells. However, ectopic IRF4 expression can augment EBV lytic gene expression induced by anti-immunoglobulin (anti-Ig) or sodium butyrate treatment in all tested lymphoma cells, whereas IRF4 knockout in Raji cells, the only BL cell line with detectable endogenous IRF4 expression, abolishes EBV lytic gene expression induced by anti-Ig, and this is accompanied by the reduction of Blimp-1 expression, whose overexpression, in turn, can rescue EBV lytic gene expression in IRF4 knockout Raji cells. Furthermore, IRF4 knockout impairs B cell receptor (BCR) signalling activation, which is required for BCR-mediated EBV reactivation. Altogether, these results demonstrate that IRF4 facilitates EBV lytic reactivation in BL cells, which involves the regulation of Blimp-1 expression and BCR signalling pathways.


Assuntos
Linfoma de Burkitt/virologia , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/genética , Fatores Reguladores de Interferon/genética , Linfócitos B/virologia , Linhagem Celular Tumoral , Regulação Viral da Expressão Gênica/genética , Humanos , Fator 1 de Ligação ao Domínio I Regulador Positivo/genética , Regiões Promotoras Genéticas/genética , Transdução de Sinais/genética , Proteínas Virais/genética , Ativação Viral/genética , Latência Viral/genética
9.
J Virol ; 90(21): 9782-9796, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27558422

RESUMO

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


Assuntos
Linfócitos B/metabolismo , Gammaherpesvirinae/genética , Linfoma de Células B/metabolismo , Receptores de Antígenos de Linfócitos B/metabolismo , Transdução de Sinais/fisiologia , Replicação Viral/genética , Receptor fas/metabolismo , Apoptose/genética , Linfócitos B/virologia , Caspases/metabolismo , Replicação do DNA/genética , Proteína Ligante Fas/metabolismo , Humanos , Interferon beta/metabolismo , Linfoma de Células B/virologia
10.
Adv Exp Med Biol ; 1018: 225-236, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29052141

RESUMO

Murine gammaherpesvirus 68 (MHV68) is a naturally occurring pathogen of murid rodents that is genetically related to the human gammaherpesviruses Epstein-Barr virus (EBV) and Kaposi sarcoma-associated herpesvirus (KSHV). Viral, immunologic, and disease parameters following experimental infection of laboratory mice with MHV68 closely resemble what occurs during primary EBV infection of humans, which suggests that MHV68 infection of mice offers a small animal model to study in general the pathogenesis of gammaherpesvirus infections. Diseases elicited by MHV68 infection include lymphoproliferative diseases, idiopathic pulmonary fibrosis, and autoimmune diseases, ailments also associated with EBV infection of humans. Furthermore, MHV68 infection also is linked to the development of vasculitis, encephalomyelitis, and other disorders that resemble pathologies with viral and nonviral etiologies in humans. This review aims to provide an overview of MHV68-associated diseases in infected mice that may provide a model for understanding basic mechanisms by which similar diseases in humans occur and can be treated.


Assuntos
Infecções por Vírus Epstein-Barr/virologia , Gammaherpesvirinae/genética , Infecções por Herpesviridae/genética , Infecções Tumorais por Vírus/genética , Animais , Linfócitos B/virologia , Modelos Animais de Doenças , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/patologia , Gammaherpesvirinae/patogenicidade , Regulação Viral da Expressão Gênica , Infecções por Herpesviridae/patologia , Infecções por Herpesviridae/virologia , Humanos , Camundongos , Infecções Tumorais por Vírus/patologia , Infecções Tumorais por Vírus/virologia , Latência Viral/genética
11.
Emerg Microbes Infect ; 13(1): 2337665, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38551145

RESUMO

Coxsackievirus B4 (CVB4) is associated with a range of acute and chronic diseases such as hand, foot, and mouth disease, myocarditis, meningitis, pancreatitis, and type 1 diabetes, affecting millions of young children annually around the world. However, no vaccine is currently available for preventing CVB4 infection. Here, we report the development of inactivated viral particle vaccines for CVB4. Two types of inactivated CVB4 particles were prepared from CVB4-infected cell cultures as vaccine antigens, including F-particle (also called mature virion) consisting of VP1, VP3, VP2, and VP4 subunit proteins, and E-particle (also called empty capsid) which is made of VP1, VP3, and uncleaved VP0. Both the inactivated CVB4 F-particle and E-particle were able to potently elicit neutralizing antibodies in mice, despite slightly lower neutralizing antibody titres seen with the E-particle vaccine after the third immunization. Importantly, we demonstrated that passive transfer of either anti-F-particle or anti-E-particle sera could completely protect the recipient mice from lethal CVB4 challenge. Our study not only defines the immunogenicity and protective efficacy of inactivated CVB4 F-particle and E-particle but also reveals the central role of neutralizing antibodies in anti-CVB4 protective immunity, thus providing important information that may accelerate the development of inactivated CVB4 vaccines.


Assuntos
Vacinas , Vacinas Virais , Humanos , Criança , Animais , Camundongos , Pré-Escolar , Anticorpos Antivirais , Anticorpos Neutralizantes , Imunização , Vacinação
12.
PLoS Pathog ; 7(9): e1002220, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21931547

RESUMO

Human gammaherpesviruses are associated with the development of lymphoproliferative diseases and B cell lymphomas, particularly in immunosuppressed hosts. Understanding the molecular mechanisms by which human gammaherpesviruses cause disease is hampered by the lack of convenient small animal models to study them. However, infection of laboratory strains of mice with the rodent virus murine gammaherpesvirus 68 (MHV68) has been useful in gaining insights into how gammaherpesviruses contribute to the genesis and progression of lymphoproliferative lesions. In this report we make the novel observation that MHV68 infection of murine day 15 fetal liver cells results in their immortalization and differentiation into B plasmablasts that can be propagated indefinitely in vitro, and can establish metastasizing lymphomas in mice lacking normal immune competence. The phenotype of the MHV68 immortalized B cell lines is similar to that observed in lymphomas caused by KSHV and resembles the favored phenotype observed during MHV68 infection in vivo. All established cell lines maintained the MHV68 genome, with limited viral gene expression and little or no detectable virus production - although virus reactivation could be induced upon crosslinking surface Ig. Notably, transcription of the genes encoding the MHV68 viral cyclin D homolog (v-cyclin) and the homolog of the KSHV latency-associated nuclear antigen (LANA), both of which are conserved among characterized γ2-herpesviruses, could consistently be detected in the established B cell lines. Furthermore, we show that the v-cyclin and LANA homologs are required for MHV68 immortalization of murine B cells. In contrast the M2 gene, which is unique to MHV68 and plays a role in latency and virus reactivation in vivo, was dispensable for B cell immortalization. This new model of gammaherpesvirus-driven B cell immortalization and differentiation in a small animal model establishes an experimental system for detailed investigation of the role of gammaherpesvirus gene products and host responses in the genesis and progression of gammaherpesvirus-associated lymphomas, and presents a convenient system to evaluate therapeutic modalities.


Assuntos
Antígenos Virais/metabolismo , Linfócitos B/virologia , Transformação Celular Viral , Ciclina D/metabolismo , Proteínas Nucleares/metabolismo , Rhadinovirus/genética , Rhadinovirus/patogenicidade , Animais , Linhagem Celular Transformada , Citometria de Fluxo , Regulação Viral da Expressão Gênica , Rearranjo Gênico , Genes Virais , Fígado/citologia , Linfoma de Células B/virologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Modelos Animais , Fenótipo , Plasmócitos/virologia , Rhadinovirus/fisiologia , Análise de Sequência de RNA , Proteínas Virais/genética , Proteínas Virais/metabolismo , Replicação Viral
13.
Sci China Life Sci ; 66(10): 2329-2341, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37300753

RESUMO

Monkeypox was declared a global health emergency by the World Health Organization, and as of March 2023, 86,000 confirmed cases and 111 deaths across 110 countries have been reported. Its causal agent, monkeypox virus (MPV) belongs to a large family of double-stranded DNA viruses, Orthopoxviridae, that also includes vaccinia virus (VACV) and others. MPV produces two distinct forms of viral particles during its replication cycles: the enveloped viron (EV) that is released via exocytosis, and the mature viron (MV) that is discharged through lysis of host cells. This study was designed to develop multi-valent mRNA vaccines against monkeypox EV and MV surface proteins, and examine their efficacy and mechanism of action. Four mRNA vaccines were produced with different combinations of surface proteins from EV (A35R and B6R), MV (A29L, E8L, H3L and M1R), or EV and MV, and were administered in Balb/c mice to assess their immunogenicity potentials. A dynamic immune response was observed as soon as seven days after initial immunization, while a strong IgG response to all immunogens was detected with ELISA after two vaccinations. The higher number of immunogens contributed to a more robust total IgG response and correlating neutralizing activity against VACV, indicating the additive potential of each immunogen in generating immune response and nullifying VACV infection. Further, the mRNA vaccines elicited an antigen-specific CD4+ T cell response that is biased towards Th1. The mRNA vaccines with different combinations of EV and MV surface antigens protected a mouse model from a lethal dose VACV challenge, with the EV and MV antigens-combined vaccine offering the strongest protection. These findings provide insight into the protective mechanism of multi-valent mRNA vaccines against MPV, and also the foundation for further development of effective and safe mRNA vaccines for enhanced protection against monkeypox virus outbreak.


Assuntos
Mpox , Animais , Camundongos , Antígenos de Superfície , Vaccinia virus/genética , Proteínas de Membrana , Imunidade , Imunoglobulina G , Anticorpos Antivirais
14.
Front Psychol ; 13: 783998, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35197898

RESUMO

In the Internet era, consumers prefer products with the attributes of social responsibility. Supply chain enterprises strengthen corporate social responsibility (CSR) management for their own development. To improve CSR throughout the supply chain, it requires coordination and cooperation among the members of the supply chain. In this paper, we consider a three-tier supply chain system consisting of a supplier, a manufacturer, and a retailer and use stochastic differential game to study the CSR coordination of the supply chain. The following indicators are investigated under four decision situations, such as the optimal level of CSR effort for the supply chain members, the optimal value of profit for the supply chain members and the supply chain system, and the expectation and variance of CSR goodwill. Some important results are obtained. (i) Compared with decentralized decision-making, the optimal level of CSR effort increases for the supplier and the manufacturer under local alliance decision-making without cost sharing, whereas the optimal level of CSR effort remains unchanged for the retailer. (ii) Compared with local alliance decision-making without cost sharing, the optimal level of CSR effort remains unchanged for the supplier and the manufacturer under local alliance decision-making with cost sharing. When the sum of the marginal profit for the supplier and the manufacturer is greater than half of the marginal profit for the retailer, the optimal level of CSR effort increases for the retailer. (iii) Compared with local alliance decision-making with cost sharing, the optimal level of CSR effort increases for the supply chain members under overall alliance decision-making. (iv) From decentralized decision-making to local alliance decision-making without cost sharing, to local alliance decision-making with cost sharing, and then to overall alliance decision-making, the optimal value of profit increases for the supply chain members and the supply chain system. Also, the expectation and variance of CSR goodwill increase.

15.
Front Psychol ; 13: 1017875, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36544456

RESUMO

It is of great significance to accurately grasp the demand for air travel to promote the revival of long-distance travel and alleviate public anxiety. The main purpose of this study is to build a high-precision air travel demand forecasting framework by introducing effective Internet data. In the age of big data, passengers before traveling often look for reference groups in search engines and make travel decisions under their informational influence. The big data generated based on these behaviors can reflect the overall passenger psychology and travel demand. Therefore, based on big data mining technology, this study designed a strict dual data preprocessing method and an ensemble forecasting framework, introduced search engine data into the air travel demand forecasting process, and conducted empirical research based on the dataset composed of air travel volume of Shanghai Pudong International Airport. The results show that effective search engine data is helpful to air travel demand forecasting. This research provides a theoretical basis for the application of big data mining technology and data spatial information in air travel demand forecasting and tourism management, and provides a new idea for alleviating public anxiety.

16.
Front Psychol ; 13: 809954, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35783700

RESUMO

Before making travel plans, people often use the Internet to collect relevant information to help themselves make better decisions. Among the numerous information search channels, Internet search engine is used by the vast number of travelers because of its low cost and high efficiency. To a large extent, Internet search behavior is the external manifestation of users' psychological activities, reflecting their concerns, needs and preferences. Therefore, Internet search data can reflect the air passenger demand information to a certain extent. In this manuscript, a novel decomposition ensemble model is proposed to discuss the role of Internet search data in air passenger demand forecasting. In the empirical study, the relevant data of Shanghai Pudong International Airport and Beijing Capital International Airport are taken as samples. The results show that the proposed forecasting model can integrate the advantages of decomposition-ensemble strategy and deep learning algorithm, and achieve more accurate and reliable prediction results than all benchmark models. This further indicates that adding Internet search data into the forecasting model can effectively improve the prediction performance of air passenger demand, and can provide scientific and reliable decision support for air transport management.

17.
Front Psychol ; 13: 925028, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35928411

RESUMO

In the Internet era, with the widespread application of digital technology, the way people travel has changed. Compared with traditional taxis, more and more people prefer to choose online car-hailing. The rapid development of the online car-hailing industry has solved the problem of taxi-hailing to a certain extent, but it has also brought some new problems. To change the dilemma of the online car-hailing industry, it is necessary to strengthen the regulation of the online car-hailing industry. In this study, we consider the regulatory system composed of a local government and an enterprise and use the differential game to study the regulation of online car-hailing. In the Nash non-cooperative game, Stackelberg master-slave game, and cooperative game, we, respectively, investigate the indicators, such as the optimal regulatory effort of the government, the optimal regulatory effort of the enterprise, the optimal benefit function of the government, the optimal benefit function of the enterprise, the optimal benefit function of the system, the optimal trajectory of the service quality level for the enterprise, and the optimal trajectory of the goodwill for the enterprise. Moreover, we analyze the corresponding conclusions through examples. We obtained some important results. (i) In the Stackelberg master-slave game, the optimal ratio of the local government subsidy to the enterprise's regulatory cost is only related to the benefit distribution coefficient and has nothing to do with other factors. Moreover, when the benefit distribution coefficient is >1/3, the local government is willing to share the regulatory cost of the enterprise. Otherwise, the local government refuses to share the regulatory cost of the enterprise. (ii) Compared with the Nash non-cooperative game, the optimal regulatory effort of the local government remains unchanged in the Stackelberg master-slave game, but the optimal benefit of the local government increases. Moreover, when the benefit distribution coefficient is >1/3, both the optimal regulatory effort and the optimal benefit of the enterprise increase. (iii) Compared with the Stackelberg master-slave game, in the cooperative game, the optimal regulatory effort of both government and enterprise increases, and the system's optimal benefit also increases. (iv) From the Nash non-cooperative game to the Stackelberg master-slave game and then to the cooperative game when the benefit distribution coefficient is >1/3, the service quality level and goodwill of the enterprise all increase.

18.
PLoS Pathog ; 5(11): e1000677, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19956661

RESUMO

Gammaherpesviruses chronically infect their host and are tightly associated with the development of lymphoproliferative diseases and lymphomas, as well as several other types of cancer. Mechanisms involved in maintaining chronic gammaherpesvirus infections are poorly understood and, in particular, little is known about the mechanisms involved in controlling gammaherpesvirus reactivation from latently infected B cells in vivo. Recent evidence has linked plasma cell differentiation with reactivation of the human gammaherpesviruses EBV and KSHV through induction of the immediate-early viral transcriptional activators by the plasma cell-specific transcription factor XBP-1s. We now extend those findings to document a role for a gammaherpesvirus gene product in regulating plasma cell differentiation and thus virus reactivation. We have previously shown that the murine gammaherpesvirus 68 (MHV68) gene product M2 is dispensable for virus replication in permissive cells, but plays a critical role in virus reactivation from latently infected B cells. Here we show that in mice infected with wild type MHV68, virus infected plasma cells (ca. 8% of virus infected splenocytes at the peak of viral latency) account for the majority of reactivation observed upon explant of splenocytes. In contrast, there is an absence of virus infected plasma cells at the peak of latency in mice infected with a M2 null MHV68. Furthermore, we show that the M2 protein can drive plasma cell differentiation in a B lymphoma cell line in the absence of any other MHV68 gene products. Thus, the role of M2 in MHV68 reactivation can be attributed to its ability to manipulate plasma cell differentiation, providing a novel viral strategy to regulate gammaherpesvirus reactivation from latently infected B cells. We postulate that M2 represents a new class of herpesvirus gene products (reactivation conditioners) that do not directly participate in virus replication, but rather facilitate virus reactivation by manipulating the cellular milieu to provide a reactivation competent environment.


Assuntos
Linfócitos B/virologia , Diferenciação Celular , Gammaherpesvirinae/fisiologia , Plasmócitos/virologia , Ativação Viral , Latência Viral , Animais , Linhagem Celular Tumoral , Humanos , Linfoma de Células B/patologia , Linfoma de Células B/virologia , Camundongos , Plasmócitos/patologia , Baço/citologia , Proteínas Virais/fisiologia
19.
Front Microbiol ; 12: 736449, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34630361

RESUMO

Influenza A virus (IAV) is a major respiratory pathogen that causes seasonal and pandemic flu, being a threat to global health. Various viral and cellular factors have been characterized to support or limit IAV infection. Interleukin 16 (IL16) has been known as one of the blood signature biomarkers discriminating systemic inflammation due to viral infection vs. other etiologies. Here, we report that the level of IL16 was elevated in the serum samples, lung homogenates, and bronchoalveolar lavage fluid of IAV-infected mice. IL16 overexpression facilitated IAV replication. Conversely, loss of IL16 reduced the host susceptibility to IAV infection in vitro and in vivo. Furthermore, IL16 deficiency blocked IAV-induced body weight loss and attenuated lung injury in the infected mice. Molecular mechanism analyses further revealed that IL16 could directly inhibit IFN-ß transcription and suppress the expression of IFN-ß and IFN-stimulated gene. In conclusion, these findings demonstrate that IL16 is a supporting factor for IAV infection.

20.
iScience ; 24(11): 103209, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34746692

RESUMO

Immune activation has been shown to play a critical role in the development of schizophrenia; however its underlying mechanism remains unknown. Our report demonstrates a high-quality protein interaction network for schizophrenia (SCZ Network), constructed using our "neighborhood walk" approach in combination with "random walk with restart". The spatiotemporal expression pattern of the genes in this disease network revealed two developmental stages sensitive to perturbation by immune activation: mid-to late gestation, and adolescence. Furthermore, we induced immune activation at these stages in mice, carried out transcriptome sequencing on the mouse brains, and illustrated clear potential molecular pathways and key regulators correlating maternal immune activation during gestation and an increased risk for schizophrenia after a second immune activation at puberty. This work provides not only valuable resources for the study on molecular mechanisms underlying schizophrenia, but also a systematic strategy for the discovery of molecular pathways of complex mental disorders.

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