RESUMO
Chronic hepatitis C virus infection (HCV) causes liver inflammation and fibrosis, leading to the development of severe liver disease, such as cirrhosis or hepatocellular carcinoma (HCC). Approval of direct-acting antiviral drug combinations has revolutionized chronic HCV therapy, with virus eradication in >98% of the treated patients. The efficacy of these treatments is such that it is formally possible for cured patients to carry formerly infected cells that display irreversible transcriptional alterations directly caused by chronic HCV Infection. Combining differential transcriptomes from two different persistent infection models, we observed a major reversion of infection-related transcripts after complete infection elimination. However, a small number of transcripts were abnormally expressed in formerly infected cells. Comparison of the results obtained in proliferating and growth-arrested cell culture models suggest that permanent transcriptional alterations may be established by several mechanisms. Interestingly, some of these alterations were also observed in the liver biopsies of virologically cured patients. Overall, our data suggest a direct and permanent impact of persistent HCV infection on the host cell transcriptome even after virus elimination, possibly contributing to the development of HCC.
Assuntos
Antivirais , Hepacivirus , Hepatite C Crônica , Humanos , Antivirais/farmacologia , Antivirais/uso terapêutico , Hepacivirus/genética , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Transcriptoma , Infecção Persistente/virologia , Perfilação da Expressão Gênica , Fígado/virologia , Fígado/patologia , Carcinoma Hepatocelular/virologia , Transcrição Gênica/efeitos dos fármacosRESUMO
Human papillomavirus (HPV) type 81 has recently become one of the most common low-risk HPV types; however, literature focusing on it is limited. This study aimed to analyze the reasons for the increased detection rate of HPV81 and investigate its evolving pathogenicity. We analyzed the detection rates and trends of HPV81 in 229 061 exfoliated cervical cell samples collected from 2014 to 2023; collected samples of HPV81 single infections from two different time periods; and analyzed the allele frequencies, positive selection, viral load, persistent infection capacity, and pathogenicity of E6 and E7 genotypes. We found that the detection rate of HPV81 ranked first among the low-risk types in exfoliated cervical cells and exhibited a significantly increasing trend (p < 0.001). The frequency of the E6 prototype allele of HPV81 (n = 317) was significantly increased (p = 0.018) and demonstrated the strongest adaptive capacity. The viral load and persistent infection capacity of the E6 prototype were significantly higher than those of the mutants, thus serving as key drivers for increasing the detection rate of HPV81 and enhancing its pathogenicity. The viral load was positively correlated with persistent infection capacity and pathogenicity. Persistent infection was a crucial factor in the pathogenicity of HPV81. Successful adaptive evolution of HPV81 is accompanied by enhanced pathogenicity.
Assuntos
Genótipo , Infecções por Papillomavirus , Infecção Persistente , Polimorfismo Genético , Carga Viral , Humanos , Infecções por Papillomavirus/virologia , Feminino , Infecção Persistente/virologia , Colo do Útero/virologia , Colo do Útero/patologia , Adulto , Papillomaviridae/genética , Papillomaviridae/patogenicidade , Papillomaviridae/classificação , Papillomaviridae/isolamento & purificação , Frequência do Gene , Proteínas Oncogênicas Virais/genética , Virulência/genética , Alphapapillomavirus/genética , Alphapapillomavirus/patogenicidade , Alphapapillomavirus/classificação , Alphapapillomavirus/isolamento & purificação , Papillomavirus HumanoRESUMO
BACKGROUND: Early diagnosis and treatment of HPV persistent infection and cervical intraepithelial neoplasia, which have yet to be thoroughly characterized in Guangxi, Southwestern China, are the key preventative measures for the development of cervical cancer in women, particularly in HIV-infected women. METHODS: A retrospective study of 181 patients with HPV infection or cervical intraepithelial neoplasia who received surgical excision of lesions and were prospectively enrolled at the Fourth People's Hospital of Nanning between January 2018 and February 2023 was performed. HPV-infected patients were divided into two subgroups: HIV-infected and HIV/HPV-coinfected patients and compare differences between these groups. RESULTS: HPV16, 18, 52, and 58 were the most prevalent HPV genotypes. High-risk HPV was significantly co-infected with multiple genotypes (P = 0.0332). HIV-infected women were predisposed to HPV infection (P < 0.0001), and the development of cervical cancer at a young age (P = 0.0336) compared to HIV-uninfected women and the loop electrosurgical excision procedure (P = 0.0480) is preferred for the treatment. CONCLUSIONS: HIV infection may increase HPV prevalence and lead to cervical cancer development at a young age. The loop electrosurgical excision procedure is an efficient evaluation and treatment strategy for HIV-infected women suffering from cervical intraepithelial neoplasia.
Assuntos
Coinfecção , Infecções por HIV , Infecções por Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Humanos , Feminino , Infecções por HIV/complicações , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/virologia , Estudos Retrospectivos , Adulto , Pessoa de Meia-Idade , Displasia do Colo do Útero/virologia , Displasia do Colo do Útero/cirurgia , Displasia do Colo do Útero/complicações , Neoplasias do Colo do Útero/virologia , Neoplasias do Colo do Útero/cirurgia , Coinfecção/virologia , China/epidemiologia , Genótipo , Prevalência , Papillomaviridae/genética , Papillomaviridae/isolamento & purificação , Infecção Persistente/virologia , Adulto JovemRESUMO
Human papillomavirus (HPV)-associated malignancies account for ~5% of human cancers worldwide. Thirteen, or more, HPV types are oncogenic, but infection with these viruses is common and usually cleared within 2 years. Only infections that become persistent are associated with the development of cancer, often occurring several decades later. These cancers mostly arise in 6 different anatomical regions: 5 are anogenital (anus, cervix, penis, vagina, and vulva) and the sixth is the oropharynx. Oncogenic HPVs promote cellular proliferation and genomic instability, but the anatomical niche of the target tissue also plays an important role in the development of cancer. Cells that reside in transitional regions between different types of epithelia, such as in the anus, cervix, and oropharynx, are particularly vulnerable to oncogenesis.
Assuntos
Infecções por Papillomavirus , Humanos , Infecções por Papillomavirus/virologia , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/patologia , Feminino , Masculino , Papillomaviridae/patogenicidade , Neoplasias/virologia , Neoplasias/patologia , Neoplasias/complicações , Infecção Persistente/virologiaRESUMO
BK polyomavirus (BKPyV) was the first human polyomavirus to be isolated from an immunosuppressed kidney transplant recipient in 1971. BKPyV reactivation causes BKPyV-associated nephropathy and hemorrhagic cystitis. However, the mechanisms underlying BKPyV replication remain unclear. In the present study, we performed the long-term cultivation of COS-7 cells transfected with archetype KOM-5 DNA, which were designated as COS-BK cells. BKPyV derived from COS-BK cells was characterized by analyzing the amount of the virus based on hemagglutination, viral replication, and the production of viral protein 1 (VP1). Immunostaining showed that VP1-positive cells accounted for a small percentage of COS-BK cells. The nucleotide sequences encompassing the origin of the DNA replication of BKPyV derived from COS-BK cells were generated from KOM-5 by the deletion of an 8-bp sequence, which did not involve T antigen binding sites. BKPyV replicated most efficiently in COS-BK cells in DMEM containing 2% fetal bovine serum. These results indicate that COS-BK cells are a suitable culture system for studying the persistent infection of archetype BKPyV.
Assuntos
Vírus BK , Infecções por Polyomavirus , Replicação Viral , Vírus BK/fisiologia , Vírus BK/genética , Animais , Chlorocebus aethiops , Células COS , Infecções por Polyomavirus/virologia , Humanos , Proteínas do Capsídeo/genética , DNA Viral/genética , Infecção Persistente/virologia , Antígenos Virais de Tumores/genética , Infecções Tumorais por Vírus/virologiaRESUMO
IMPORTANCE: The human gammaherpesviruses Epstein-Barr virus and Kaposi's sarcoma-associated herpesvirus are etiologic agents of numerous B cell lymphomas. A hallmark of gammaherpesvirus infection is their ability to establish lifelong latency in B cells. However, the specific mechanisms that mediate chronic infection in B cells in vivo remain elusive. Cellular E3 ubiquitin ligases regulate numerous biological processes by catalyzing ubiquitylation and modifying protein location, function, or half-life. Many viruses hijack host ubiquitin ligases to evade antiviral host defense and promote viral fitness. Here, we used the murine gammaherpesvirus 68 in vivo system to demonstrate that the E3 ligase Cul4b is essential for this virus to establish latency in germinal center B cells. These findings highlight an essential role for this E3 ligase in promoting chronic gammaherpesvirus infection in vivo and suggest that targeted inhibition of E3 ligases may provide a novel and effective intervention strategy against gammaherpesvirus-associated diseases.
Assuntos
Linfócitos B , Gammaherpesvirinae , Infecções por Herpesviridae , Infecção Persistente , Animais , Camundongos , Linfócitos B/enzimologia , Linfócitos B/metabolismo , Linfócitos B/virologia , Proteínas Culina/metabolismo , Gammaherpesvirinae/fisiologia , Centro Germinativo/citologia , Centro Germinativo/virologia , Infecções por Herpesviridae/enzimologia , Infecções por Herpesviridae/virologia , Infecção Persistente/enzimologia , Infecção Persistente/virologia , Ubiquitinas/metabolismo , Latência ViralRESUMO
Interferons (IFNs) are cytokines that induce a global change in the cell to establish antiviral immunity. We previously demonstrated that human adenovirus (HAdV) exploits IFN-induced viral repression to persist in infected cells. Although this in vitro persistence model has been described, the mechanism behind how persistent HAdV infection is established is not well understood. In this study, we demonstrate that IFN signaling is essential for viral repression and promoting persistent infection. Cyclin-dependent kinase 4 (CDK4), an antagonist of retinoblastoma (Rb) family proteins, was shown to disrupt the viral repression induced by IFNs. Consistent with this result, knockout of the Rb family proteins pRb, p107, and/or p130 drastically reduced the effect of IFNs on viral replication. The pRb protein specifically contributed the greatest effect to IFN inhibition of viral replication. Interestingly, IFNs did not impact pRb through direct changes in protein or phosphorylation levels. Cells treated with IFNs continued to cycle normally, consistent with observations that persistently infected cells remain for long periods of time in the host and in our in vitro persistent infection model. Finally, we observed that histone deacetylase (HDAC) inhibitors activated productive viral replication in persistently infected cells in the presence of IFN. Thus, HDACs, specifically class I HDACs, which are commonly associated with Rb family proteins, play a major role in the maintenance of persistent HAdV infection in vitro. This study uncovers the critical role of pRb and class I HDACs in the IFN-induced formation of a repressor complex that promotes persistent HAdV infections. IMPORTANCE Adenoviruses are ubiquitous viruses infecting more than 90% of the human population. HAdVs cause persistent infections that may lead to serious complications in immunocompromised patients. Therefore, exploring how HAdVs establish persistent infections is critical for understanding viral reactivation in immunosuppressed individuals. The mechanism underlying HAdV persistence has not been fully explored. Here, we provide insight into the contributions of the host cell to IFN-mediated persistent HAdV infection. We found that HAdV-C5 productive infection is inhibited by an Rb-E2F-HDAC repressor complex. Treatment with HDAC inhibitors converted a persistent infection to a lytic infection. Our results suggest that this process involves the noncanonical regulation of Rb-E2F signaling. This study provides insight into a highly prevalent human pathogen, bringing a new level of complexity and understanding to the replicative cycle.
Assuntos
Infecções por Adenovirus Humanos , Adenovírus Humanos , Interferons , Infecção Persistente , Infecções por Adenovirus Humanos/imunologia , Adenovírus Humanos/fisiologia , Fatores de Transcrição E2F/imunologia , Histona Desacetilases/imunologia , Humanos , Interferons/imunologia , Infecção Persistente/imunologia , Infecção Persistente/virologia , Proteína do Retinoblastoma/imunologiaRESUMO
Human Papillomaviruses have co-evolved with their human host, with each of the over 200 known HPV types infecting distinct epithelial niches to cause diverse disease pathologies. Despite the success of prophylactic vaccines in preventing high-risk HPV infection, the development of HPV anti-viral therapies has been hampered by the lack of enzymatic viral functions, and by difficulties in translating the results of in vitro experiments into clinically useful treatment regimes. In this review, we discuss recent advances in anti-HPV drug development, and highlight the importance of understanding persistent HPV infections for future anti-viral design. In the infected epithelial basal layer, HPV genomes are maintained at a very low copy number, with only limited viral gene expression; factors which allow them to hide from the host immune system. However, HPV gene expression confers an elevated proliferative potential, a delayed commitment to differentiation, and preferential persistence of the infected cell in the epithelial basal layer, when compared to their uninfected neighbours. To a large extent, this is driven by the viral E6 protein, which functions in the HPV life cycle as a modulator of epithelial homeostasis. By targeting HPV gene products involved in the maintenance of the viral reservoir, there appears to be new opportunities for the control or elimination of chronic HPV infections.
Assuntos
Alphapapillomavirus/efeitos dos fármacos , Antivirais/uso terapêutico , Infecções por Papillomavirus/tratamento farmacológico , Infecção Persistente/tratamento farmacológico , Antivirais/farmacologia , Desenvolvimento de Medicamentos , Epitélio/efeitos dos fármacos , Epitélio/patologia , Epitélio/virologia , Homeostase/efeitos dos fármacos , Humanos , Proteínas Oncogênicas Virais/antagonistas & inibidores , Proteínas Oncogênicas Virais/metabolismo , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Infecção Persistente/patologia , Infecção Persistente/virologiaRESUMO
Invariant NK T (iNKT) cells are implicated in viral clearance; however, their role in hepatitis C virus (HCV) infection remains controversial. Here, iNKT cells were studied during different stages of HCV infection. iNKT cells from patients with acute HCV infection and people who inject drugs (PWID) with chronic or spontaneously resolved HCV infection were characterized by flow cytometry. In a longitudinal analysis during acute HCV infection, frequencies of activated CD38+ iNKT cells reproducibly declined in spontaneously resolving patients, whereas they were persistently elevated in patients progressing to chronic infection. During the first year of infection, the frequency of activated CD38+ or CD69+ iNKT cells strongly correlated with alanine transaminase levels with particularly pronounced correlations in spontaneously resolving patients. Increased frequencies of activated iNKT cells in chronic HCV infection were confirmed in cross-sectional analyses of PWID with chronic or spontaneously resolved HCV infection; however, no apparent functional differences were observed with various stimulation protocols. Our data suggest that iNKT cells are activated during acute hepatitis C and that activation is sustained in chronic infection. The correlation between the frequency of activated iNKT cells and alanine transaminase may point toward a role of iNKT cells in liver damage.
Assuntos
ADP-Ribosil Ciclase 1/análise , Antígenos CD/análise , Antígenos de Diferenciação de Linfócitos T/análise , Hepacivirus , Hepatite C , Lectinas Tipo C/análise , Ativação Linfocitária/imunologia , Células T Matadoras Naturais , Doença Aguda , Alanina Transaminase/sangue , Estudos Transversais , Hepacivirus/isolamento & purificação , Hepacivirus/patogenicidade , Hepacivirus/fisiologia , Hepatite C/sangue , Hepatite C/fisiopatologia , Hepatite C/virologia , Humanos , Células T Matadoras Naturais/imunologia , Células T Matadoras Naturais/virologia , Infecção Persistente/imunologia , Infecção Persistente/virologia , Remissão Espontânea , Carga Viral/imunologiaRESUMO
Coronavirus disease 2019 (COVID-19) infection results in both acute mortality and persistent and/or recurrent disease in patients with hematologic malignancies, but the drivers of persistent infection in this population are unknown. We found that B-cell lymphomas were at particularly high risk for persistent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positivity. Further analysis of these patients identified discrete risk factors for initial disease severity compared with disease chronicity. Active therapy and diminished T-cell counts were drivers of acute mortality in COVID-19-infected patients with lymphoma. Conversely, B cell-depleting therapy was the primary driver of rehospitalization for COVID-19. In patients with persistent SARS-CoV-2 positivity, we observed high levels of viral entropy consistent with intrahost viral evolution, particularly in patients with impaired CD8+ T-cell immunity. These results suggest that persistent COVID-19 infection is likely to remain a risk in patients with impaired adaptive immunity and that additional therapeutic strategies are needed to enable viral clearance in this high-risk population. SIGNIFICANCE: We describe the largest cohort of persistent symptomatic COVID-19 infection in patients with lymphoid malignancies and identify B-cell depletion as the key immunologic driver of persistent infection. Furthermore, we demonstrate ongoing intrahost viral evolution in patients with persistent COVID-19 infection, particularly in patients with impaired CD8+ T-cell immunity.This article is highlighted in the In This Issue feature, p. 1.
Assuntos
COVID-19/imunologia , COVID-19/virologia , Neoplasias Hematológicas/imunologia , Neoplasias Hematológicas/virologia , Infecção Persistente/imunologia , Infecção Persistente/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos B/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , SARS-CoV-2/imunologia , Linfócitos T/imunologiaRESUMO
Persistent infection with high-risk human papillomavirus (HR-HPV) is the most important determinate in the development of cervical cancer, and cervical microecology can modulate cervical viral infection. However, few studies have been conducted on the microecological analysis of cervical diseases using strict physiological factors. This study investigated the characteristics and dynamics of cervical microecology in childbearing-age Chinese women with different degrees of HR-HPV-positive cervical lesions. A total of 168 subjects were selected according to the selection criteria, including healthy HPV-negative individuals (n = 29), HR-HPV-infected individuals (n = 29), low-grade squamous intraepithelial lesion individuals (LSIL, n = 32), high-grade squamous intraepithelial lesion individuals (HSIL, n = 40), and cervical cancer individuals (n = 38). We sampled cervical secretions from each subject and performed comparative analysis using the 16S rRNA sequencing method. Comparison analysis showed that Lactobacillus and Ignatzschineria were the dominant genera in the healthy group, while Gardnerella and Prevotella were more enriched in the disease groups. Based on the taxa composition, we roughly divided the development of cervical cancer into two phases: phase I was from healthy status to HR-HPV infection and LSIL; phase II was from LSIL to HSIL and cervical cancer. Different interactions among different genera were observed in different groups. Prevotella inhibited the abundance of Lactobacillus in the healthy group, while Prevotella inhabited the abundance of Gardnerella in the other groups. In the HR-HPV infection group, Ignatzschineria and Enterococcus showed a positive interaction but dissociated with the increase in cervical lesions, which might eventually lead to a continuous decrease in the abundances of Lactobacillus and Ignatzschineria.
Assuntos
Colo do Útero , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Vagina , Adulto , Bactérias/genética , Biodiversidade , Colo do Útero/microbiologia , Colo do Útero/patologia , Colo do Útero/virologia , Feminino , Humanos , Papillomaviridae/genética , Infecções por Papillomavirus/microbiologia , Infecção Persistente/microbiologia , Infecção Persistente/virologia , RNA Ribossômico 16S/genética , Microambiente Tumoral , Neoplasias do Colo do Útero/microbiologia , Neoplasias do Colo do Útero/virologia , Vagina/microbiologia , Vagina/virologia , Adulto JovemRESUMO
BACKGROUND: There is growing evidence that antibody responses play a role in the resolution of SARS-CoV-2 infection. Patients with primary or secondary antibody deficiency are at increased risk of persistent infection. This challenging clinical scenario is associated with adverse patient outcome and potentially creates an ecological niche for the evolution of novel SARS-CoV-2 variants with immune evasion capacity. Case reports and/or series have implied a therapeutic role for convalescent plasma (CP) to secure virological clearance, although concerns have been raised about the effectiveness of CP and its potential to drive viral evolution, and it has largely been withdrawn from clinical use in the UK. CASE PRESENTATION: We report two cases in which persistent SARS-CoV-2 infection was cleared following administration of the monoclonal antibody combination casirivimab and imdevimab (REGN-COV2, Ronapreve). A 55-year-old male with follicular lymphoma, treated with B cell depleting therapy, developed SARS-CoV-2 infection in September 2020 which then persisted for over 200 days. He was hospitalised on four occasions with COVID-19 and suffered debilitating fatigue and malaise throughout. There was no clinical response to antiviral therapy with remdesivir or CP, and SARS-CoV-2 was consistently detected in nasopharyngeal swabs. Intrahost evolution of several spike variants of uncertain significance was identified by viral sequence analysis. Delivery of REGN-COV2, in combination with remdesivir, was associated with clinical improvement and viral clearance within 6 days, which was sustained for over 150 days despite immunotherapy for relapsed follicular lymphoma. The second case, a 68-year-old female with chronic lymphocytic leukaemia on ibrutinib, also developed persistent SARS-CoV-2 infection. Despite a lack of response to remdesivir, infection promptly cleared following REGN-COV2 in combination with remdesivir, accompanied by resolution of inflammation and full clinical recovery that has been maintained for over 290 days. CONCLUSIONS: These cases highlight the potential benefit of REGN-COV2 as therapy for persistent SARS-CoV-2 infection in antibody deficient individuals, including after failure of CP treatment. Formal clinical studies are warranted to assess the effectiveness of REGN-COV2 in antibody-deficient patients, especially in light of the emergence of variants of concern, such as Omicron, that appear to evade REGN-COV2 neutralisation.
Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Tratamento Farmacológico da COVID-19 , Infecção Persistente/virologia , Idoso , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes , COVID-19/terapia , Combinação de Medicamentos , Feminino , Humanos , Imunização Passiva , Linfoma Folicular , Masculino , Pessoa de Meia-Idade , Infecção Persistente/tratamento farmacológico , SARS-CoV-2 , Resultado do Tratamento , Soroterapia para COVID-19RESUMO
Adult T-cell leukemia/lymphoma (ATLL) is an aggressive malignancy of CD4+ T-cells associated with HTLV-1 infection. In this study, we used the model of immunodeficient NSG mice reconstituted with a functional human immune system (HIS) to investigate early events in HTLV-1 pathogenesis. Upon infection, human T-cells rapidly increased in the blood and lymphoid tissues, particularly CD4+CD25+ T-cells. Proliferation of CD4+ T-cells in the spleen and mesenteric lymph nodes (MLN) correlated with HTLV-1 proviral load and CD25 expression. In addition, splenomegaly, a common feature of ATLL in humans, was also observed. CD4+ and CD8+ T-cells predominantly displayed an effector memory phenotype (CD45RA-CCR7-) and expressed CXCR3 and CCR5 chemokine receptors, suggesting the polarization into a Th1 phenotype. Activated CD8+ T-cells expressed granzyme B and perforin; however, the interferon-γ response by these cells was limited, possibly due to elevated PD-1 expression and increased frequency of CD4+FoxP3+ regulatory T-cells in MLN. Thus, HTLV-1-infected HIS-NSG mice reproduced several characteristics of infection in humans, and it may be helpful to investigate ATLL-related events and to perform preclinical studies. Moreover, aspects of chronic infection were already present at early stages in this experimental model. Collectively, we suggest that HTLV-1 infection modulates host immune responses to favor viral persistence.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Diferenciação Celular/imunologia , Infecções por HTLV-I/virologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Infecções por HTLV-I/imunologia , Vírus Linfotrópico T Tipo 1 Humano/metabolismo , Humanos , Leucemia-Linfoma de Células T do Adulto/imunologia , Leucemia-Linfoma de Células T do Adulto/patologia , Leucemia-Linfoma de Células T do Adulto/virologia , Antígenos Comuns de Leucócito/metabolismo , Camundongos , Infecção Persistente/imunologia , Infecção Persistente/virologiaRESUMO
The ability to establish long term persistent infection is a feature of human papillomaviruses. The available evidence is that this ability is a consequence of a complex local immune milieu whereby innate immune receptors and signalling pathway cascades are inhibited by HPV early proteins resulting in failure of dendritic cell maturation, antigen processing and presentation and activation of cytotoxic antigen specific T cell responses. The development of cutaneous and mucosal infection models with the mouse papillomavirus MmuPV1 and the access to multiple gene deficient strains is providing the frame work to dissect the mechanisms underlying these complex host virus interactions.
Assuntos
Interações entre Hospedeiro e Microrganismos/imunologia , Evasão da Resposta Imune , Papillomaviridae/imunologia , Papillomaviridae/patogenicidade , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/virologia , Infecção Persistente/virologia , Animais , Apresentação de Antígeno , Células Dendríticas , Humanos , Infecção Persistente/imunologia , Linfócitos TRESUMO
It remains controversial how interferon (IFN) response contributes to hepatitis B virus (HBV) control and pathogenesis. A previous study identified that hydrodynamic injection (HI) of type I IFN (IFN-I) inducer polyinosinic-poly(C) [poly(I·C)] leads to HBV clearance in a chronic HBV mouse model. However, recent studies have suggested that premature IFN-I activation in the liver may facilitate HBV persistence. In the present study, we investigated how the early IFN-I response induces an immunosuppressive signaling cascade and thus causes HBV persistence. We performed HI of the plasmid adeno-associated virus (pAAV)/HBV1.2 into adult BALB/c mice to establish an adult acute HBV replication model. Activation of the IFN-I signaling pathway following poly(I·C) stimulation or murine cytomegalovirus (MCMV) infection resulted in subsequent HBV persistence. HI of poly(I·C) with the pAAV/HBV1.2 plasmid resulted in not only the production of IFN-I and the anti-inflammatory cytokine interleukin-10 (IL-10) but also the expansion of intrahepatic regulatory T cells (Tregs), Kupffer cells (KCs), and myeloid-derived suppressor cells (MDSCs), all of which impaired the T cell response. However, when poly(I·C) was injected at day 14 after the HBV plasmid injection, it significantly enhanced HBV-specific T cell responses. In addition, interferon-alpha/beta receptor (IFNAR) blockade rescued T cell response by downregulating IL-10 expression and decreasing Treg and KC expansion. Consistently, Treg depletion or IL-10 blockade also controlled HBV replication. IMPORTANCE IFN-I plays a double-edged sword role during chronic HBV infection. Here, we identified that application of IFN-I at different time points causes contrast outcomes. Activation of the IFN-I pathway before HBV replication induces an immunosuppressive signaling cascade in the liver and consequently caused HBV persistence, while IFN-I activation post HBV infection enhances HBV-specific T cell responses and thus promotes HBV clearance. This result provided an important clue to the mechanism of HBV persistence in adult individuals.
Assuntos
Vírus da Hepatite B/imunologia , Hepatite B/imunologia , Interferon Tipo I/imunologia , Fígado/imunologia , Infecção Persistente/virologia , Transdução de Sinais/imunologia , Animais , Modelos Animais de Doenças , Fígado/virologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Infecção Persistente/imunologiaRESUMO
BK polyomavirus (BKPyV) is a small nonenveloped DNA virus that establishes a ubiquitous, asymptomatic, and lifelong persistent infection in at least 80% of the world's population. In some immunosuppressed transplant recipients, BKPyV reactivation causes polyomavirus-associated nephropathy and hemorrhagic cystitis. We report a novel in vitro model of BKPyV persistence and reactivation using a BKPyV natural host cell line. In this system, viral genome loads remain constant for various times after establishment of persistent infection, during which BKPyV undergoes extensive random genome recombination. Certain recombination events result in viral DNA amplification and protein expression, resulting in production of viruses with enhanced replication ability. IMPORTANCE BK polyomavirus (BKPyV) generally establishes a persistent subclinical infection in healthy individuals but can cause severe disease in transplant recipients. While an in vitro model to study acute replication exists, no practical model with which to study BKPyV persistence is currently available. We established a BKPyV persistence model in cell culture. Our model reveals that the virus can persist for various periods of time before random recombination of the viral genome leads to enhanced replication.
Assuntos
Vírus BK/genética , Técnicas de Cultura de Células/métodos , Genoma Viral , Infecção Persistente/virologia , Infecções por Polyomavirus/virologia , Ativação Viral , Vírus BK/fisiologia , Linhagem Celular , DNA Viral/genética , DNA Viral/metabolismo , Humanos , Recombinação Genética , Replicação ViralRESUMO
There is strong evidence that equine parvovirus-hepatitis (EqPV-H) is associated with the onset of Theiler's disease, an acute hepatic necrosis, in horses. However, the impact of this virus on other hepatopathies remains unknown. The objective of this retrospective study was to evaluate the prevalence and quantify the viral loads of EqPV-H in formalin-fixed, paraffin-embedded equine and donkey livers with various histopathologic abnormalities. The pathologies included cirrhosis, circulatory disorders of the liver, toxic and metabolic hepatic diseases as well as neoplastic and inflammatory diseases (n = 84). Eight normal liver samples were included for comparison as controls. EqPV-H DNA was qualitatively and quantitatively measured by real-time PCR and digital PCR, respectively. The virus was detected in two livers originating from horses diagnosed with abdominal neoplasia and liver metastasis (loads of 5 × 103 and 9.5 × 103 genome equivalents per million cells). The amount of viral nucleic acids measured indicates chronic infection or persistence of EqPV-H, which might have been facilitated by the neoplastic disease. In summary, this study did not provide evidence for EqPV-H being involved in hepatopathies other than Theiler's disease.
Assuntos
Vírus de Hepatite/genética , Hepatite Viral Animal/diagnóstico , Hepatopatias/diagnóstico , Hepatopatias/veterinária , Fígado/patologia , Programas de Rastreamento/veterinária , Infecções por Parvoviridae/diagnóstico , Parvovirus/genética , Animais , Equidae/virologia , Feminino , Hepatite Viral Animal/epidemiologia , Doenças dos Cavalos/diagnóstico , Doenças dos Cavalos/virologia , Cavalos/virologia , Fígado/virologia , Hepatopatias/epidemiologia , Hepatopatias/virologia , Masculino , Infecções por Parvoviridae/epidemiologia , Parvovirus/isolamento & purificação , Infecção Persistente/diagnóstico , Infecção Persistente/virologia , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Testes Sorológicos , Carga ViralRESUMO
INTRODUCTION: The purpose of this study was to detect the expression of local cytokines in cervical mucosa between patients with transient and persistent HR-HPV infection with or without CIN. METHODOLOGY: A total of 150 patients who were diagnosed as HR-HPV infection in Tianjin Central Hospital of Obstetrics and Gynecology from January 2016 to December 2016 were included in this study. The expression levels of 9 cytokines in 150 patients with HR-HPV infection, including interleukin (IL)-1ß, IL-4, IL-6, IL-8, IL-10, IL-12, IL-12p70, IL-21, interferon (IFN)-γ and tumor necrosis factor (TNF)-α, were simultaneously measured by using a multiplex immunoassay. Moreover, HR-HPV genotype was performed by using pyrosequencing. The association between cytokines and HPV genotype was also investigated. RESULTS: There was a statistically significant difference in IL-1ß level between patients with HPV transient infection and HPV persistent infection (p = 0.041). There were statistically significant differences in the levels of IL-1ß, IL-10, IL-21 and TNF-α between patients with low grade squamous intraepithelial lesion (LSIL) and high grade squamous intraepithelial lesion (HSIL) (p = 0.011, p = 0.008, p = 0.046 and p = 0.019, respectively). CONCLUSIONS: Pro-inflammatory cytokines, IL-1ß and TNF-α, and Th2 type cytokines, IL-10 and IL-21, became stronger in cervical mucosa with the progression of CIN. IL-1ß may be advantageous for HR-HPV persistent infection.
Assuntos
Citocinas/metabolismo , Papillomaviridae , Infecções por Papillomavirus/virologia , Displasia do Colo do Útero/virologia , Muco do Colo Uterino/metabolismo , China , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/imunologia , Infecção Persistente/imunologia , Infecção Persistente/virologia , Esfregaço Vaginal , Displasia do Colo do Útero/imunologiaRESUMO
BACKGROUND AND AIMS: Hepatitis C virus (HCV) leads to a high rate of chronic infection and T cell dysfunction. Although it is well known that chronic antigenic stimulation is a driving force for impaired T cell functions, the precise mechanisms underlying immune activation-induced T cell dysfunctions during HCV infection remain elusive. APPROACH AND RESULTS: Here, we demonstrated that circulating CD4+ T cells from patients who are chronically HCV-infected exhibit an immune activation status, as evidenced by the overexpression of cell activation markers human leukocyte antigen-antigen D-related, glucose transporter 1, granzyme B, and the short-lived effector marker CD127- killer cell lectin-like receptor G1+ . In contrast, the expression of stem cell-like transcription factor T cell factor 1 and telomeric repeat-binding factor 2 (TRF2) are significantly reduced in CD4+ T cells from patients who are chronically HCV-infected compared with healthy participants (HP). Mechanistic studies revealed that CD4+ T cells from participants with HCV exhibit phosphoinositide 3-kinase/Akt/mammalian target of rapamycin signaling hyperactivation on T cell receptor stimulation, promoting proinflammatory effector cell differentiation, telomeric DNA damage, and cellular apoptosis. Inhibition of Akt signaling during T cell activation preserved the precursor memory cell population and prevented inflammatory effector cell expansion, DNA damage, and apoptotic death. Moreover, knockdown of TRF2 reduced HP T cell stemness and triggered telomeric DNA damage and cellular apoptosis, whereas overexpression of TRF2 in CD4 T cells prevented telomeric DNA damage. CONCLUSIONS: These results suggest that modulation of immune activation through inhibiting Akt signaling and protecting telomeres through enhancing TRF2 expression may open therapeutic strategies to fine tune the adaptive immune responses in the setting of persistent immune activation and inflammation during chronic HCV infection.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular/imunologia , Dano ao DNA/imunologia , Hepacivirus/genética , Hepatite C Crônica/genética , Hepatite C Crônica/imunologia , Telômero/genética , Adulto , Idoso , Apoptose/genética , Apoptose/imunologia , Células Cultivadas , Dano ao DNA/genética , Feminino , Técnicas de Silenciamento de Genes/métodos , Hepatite C Crônica/virologia , Humanos , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Infecção Persistente/genética , Infecção Persistente/imunologia , Infecção Persistente/virologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Viral/genética , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Serina-Treonina Quinases TOR/metabolismo , Proteína 2 de Ligação a Repetições Teloméricas/genética , Proteína 2 de Ligação a Repetições Teloméricas/metabolismo , Transdução Genética/métodos , Adulto JovemRESUMO
BACKGROUND: Male circumcision reduces the risk of human immunodeficiency virus infection in men. We assessed the effect of male circumcision on the incidence and natural history of human papillomavirus (HPV) in a randomized clinical trial in Kisumu, Kenya. METHODS: Sexually active, 18- to 24-year-old men provided penile exfoliated cells for HPV DNA testing every 6 months for 2 years. HPV DNA was detected via GP5+/6+ PCR in glans/coronal sulcus and in shaft samples. HPV incidence and persistence were assessed by intent-to-treat analyses. RESULTS: A total of 2,193 men participated (1,096 randomized to circumcision; 1,097 controls). HPV prevalence was 50% at baseline for both groups and dropped to 23.7% at 24 months in the circumcision group, and 41.0% in control group. Incident infection of any HPV type over 24 months was lower among men in the circumcision group than in the control group [HR = 0.61; 95% confidence interval (CI), 0.52-0.72]. Clearance rate of any HPV infection over 24 months was higher in the circumcision group than in the control group (HR = 1.87; 95% CI, 1.49-2.34). Lower HPV point-prevalence, lower HPV incidence, and higher HPV clearance in the circumcision group were observed in glans but not in shaft samples. CONCLUSION: Male circumcision reduced the risk of HPV acquisition and reinfection, and increased HPV clearance in the glans. IMPACT: Providing voluntary, safe, and affordable male circumcision should help reduce HPV infections in men, and consequently, HPV-associated disease in their partners.