RESUMO
Immune responses to Epstein-Barr virus (EBV) infection synergize with the main genetic risk factor HLA-DRB1*15:01 (HLA-DR15) to increase the likelihood to develop the autoimmune disease multiple sclerosis (MS) at least sevenfold. In order to gain insights into this synergy, we investigated HLA-DR15 positive human immune compartments after reconstitution in immune-compromised mice (humanized mice) with and without EBV infection. We detected elevated activation of both CD4+ and CD8+ T cells in HLA-DR15 donor-reconstituted humanized mice at steady state, even when compared to immune compartments carrying HLA-DRB1*04:01 (HLA-DR4), which is associated with other autoimmune diseases. Increased CD8+ T cell expansion and activation was also observed in HLA-DR15 donor-reconstituted humanized mice after EBV infection. Despite this higher immune activation, EBV viral loads were less well controlled in the context of HLA-DR15. Indeed, HLA-DR15-restricted CD4+ T cell clones recognized EBV-transformed B cell lines less efficiently and demonstrated cross-reactivity toward allogeneic target cells and one MS autoantigen. These findings suggest that EBV as one of the main environmental risk factors and HLA-DR15 as the main genetic risk factor for MS synergize by priming hyperreactive T-cell compartments, which then control the viral infection less efficiently and contain cross-reactive CD4+ T cell clones.
Assuntos
Infecções por Vírus Epstein-Barr/imunologia , Subtipos Sorológicos de HLA-DR/imunologia , Esclerose Múltipla/imunologia , Imunidade Adaptativa , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Reações Cruzadas , Modelos Animais de Doenças , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/virologia , Predisposição Genética para Doença , Antígeno HLA-A2/genética , Antígeno HLA-A2/imunologia , Subtipos Sorológicos de HLA-DR/genética , Herpesvirus Humano 4/imunologia , Humanos , Isoantígenos , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Camundongos Transgênicos , Esclerose Múltipla/etiologia , Esclerose Múltipla/genética , Bainha de Mielina/imunologia , Fatores de RiscoRESUMO
Post-transplant lymphoproliferative disorder (PTLD) is a potentially fatal complication after organ transplantation frequently associated with the Epstein-Barr virus (EBV). Immunosuppressive treatment is thought to allow the expansion of EBV-infected B cells, which often express all eight oncogenic EBV latent proteins. Here, we assessed whether HLA-A2 transgenic humanized NSG mice treated with the immunosuppressant FK506 could be used to model EBV-PTLD. We found that FK506 treatment of EBV-infected mice led to an elevated viral burden, more frequent tumor formation and diminished EBV-induced T cell responses, indicative of reduced EBV-specific immune control. EBV latency III and lymphoproliferation-associated cellular transcripts were up-regulated in B cells from immunosuppressed animals, akin to the viral and host gene expression pattern found in EBV-PTLD. Utilizing an unbiased gene expression profiling approach, we identified genes differentially expressed in B cells of EBV-infected animals with and without FK506 treatment. Upon investigating the most promising candidates, we validated sCD30 as a marker of uncontrolled EBV proliferation in both humanized mice and in pediatric patients with EBV-PTLD. High levels of sCD30 have been previously associated with EBV-PTLD in patients. As such, we believe that humanized mice can indeed model aspects of EBV-PTLD development and may prove useful for the safety assessment of immunomodulatory therapies.
Assuntos
Transtornos Linfoproliferativos/imunologia , Transtornos Linfoproliferativos/virologia , Tacrolimo/farmacologia , Animais , Linfócitos B/metabolismo , DNA Viral , Modelos Animais de Doenças , Infecções por Vírus Epstein-Barr/virologia , Feminino , Perfilação da Expressão Gênica/métodos , Antígeno HLA-A2 , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Herpesvirus Humano 4/patogenicidade , Humanos , Hospedeiro Imunocomprometido , Imunossupressores/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos Transgênicos , Transplante de Órgãos/efeitos adversos , Transcriptoma/genética , Carga ViralRESUMO
[This corrects the article DOI: 10.1371/journal.ppat.1008477.].
RESUMO
The oncogenic Epstein Barr virus (EBV) infects the majority of the human population and usually persists within its host for life without symptoms. The EBV oncoproteins nuclear antigen 3A (EBNA3A) and 3C (EBNA3C) are required for B cell transformation in vitro and are expressed in EBV associated immunoblastic lymphomas in vivo. In order to address the necessity of EBNA3A and EBNA3C for persistent EBV infection in vivo, we infected NOD-scid γcnull mice with reconstituted human immune system components (huNSG mice) with recombinant EBV mutants devoid of EBNA3A or EBNA3C expression. These EBV mutants established latent infection in secondary lymphoid organs of infected huNSG mice for at least 3 months, but did not cause tumor formation. Low level viral persistence in the absence of EBNA3A or EBNA3C seemed to be supported primarily by proliferation with the expression of early latent EBV gene products transitioning into absent viral protein expression without elevated lytic replication. In vitro, EBNA3A and EBNA3C deficient EBV infected B cells could be rescued from apoptosis through CD40 stimulation, mimicking T cell help in secondary lymphoid tissues. Thus, even in the absence of the oncogenes EBNA3A and 3C, EBV can access a latent gene expression pattern that is reminiscent of EBV persistence in healthy virus carriers without prior expression of its whole growth transforming program.
Assuntos
Linfócitos B/virologia , Infecções por Vírus Epstein-Barr/virologia , Antígenos Nucleares do Vírus Epstein-Barr/metabolismo , Herpesvirus Humano 4/patogenicidade , Animais , Linfócitos B/metabolismo , Células Cultivadas , Infecções por Vírus Epstein-Barr/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Camundongos TransgênicosRESUMO
Kaposi sarcoma associated herpesvirus (KSHV) is associated with around 1% of all human tumors, including the B cell malignancy primary effusion lymphoma (PEL), in which co-infection with the Epstein Barr virus (EBV) can almost always be found in malignant cells. Here, we demonstrate that KSHV/EBV co-infection of mice with reconstituted human immune systems (humanized mice) leads to IgM responses against both latent and lytic KSHV antigens, and expansion of central and effector memory CD4+ and CD8+ T cells. Among these, KSHV/EBV dual-infection allows for the priming of CD8+ T cells that are specific for the lytic KSHV antigen K6 and able to kill KSHV/EBV infected B cells. This suggests that K6 may represent a vaccine antigen for the control of KSHV and its associated pathologies in high seroprevalence regions, such as Sub-Saharan Africa.
Assuntos
Linfócitos B , Linfócitos T CD8-Positivos , Herpesvirus Humano 8 , Animais , Herpesvirus Humano 8/imunologia , Humanos , Linfócitos B/imunologia , Camundongos , Linfócitos T CD8-Positivos/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/virologia , Coinfecção/imunologia , Coinfecção/virologia , Linfócitos T CD4-Positivos/imunologia , Herpesvirus Humano 4/imunologia , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/virologia , Imunoglobulina M/imunologia , Antígenos Virais/imunologia , Camundongos SCID , Linfoma de Efusão Primária/imunologia , Linfoma de Efusão Primária/virologia , Anticorpos Antivirais/imunologiaRESUMO
Metastatic disease is a major cause of death for patients with melanoma. Melanoma cells can become metastatic not only due to cell-intrinsic plasticity but also due to cancer-induced protumorigenic remodeling of the immune microenvironment. Here, we report that innate immune surveillance by natural killer (NK) cells is bypassed by human melanoma cells expressing the stem cell marker NGFR. Using in vitro and in vivo cytotoxic assays, we show that NGFR protects melanoma cells from NK cell-mediated killing and, furthermore, boosts metastasis formation in a mouse model with adoptively transferred human NK cells. Mechanistically, NGFR leads to down-regulation of NK cell activating ligands and simultaneous up-regulation of the fatty acid stearoyl-coenzyme A desaturase (SCD) in melanoma cells. Notably, pharmacological and small interfering RNA-mediated inhibition of SCD reverted NGFR-induced NK cell evasion in vitro and in vivo. Hence, NGFR orchestrates immune control antagonizing pathways to protect melanoma cells from NK cell clearance, which ultimately favors metastatic disease.
Assuntos
Antineoplásicos , Melanoma , Camundongos , Animais , Humanos , Linhagem Celular Tumoral , Melanoma/patologia , Células Matadoras Naturais , Lipídeos , Microambiente Tumoral , Proteínas do Tecido Nervoso/metabolismo , Receptores de Fator de Crescimento Neural/metabolismoRESUMO
To better understand the development of SARS-CoV-2-specific immunity over time, a detailed evaluation of humoral and cellular responses is required. Here, we characterize anti-Spike (S) IgA and IgG in a representative population-based cohort of 431 SARS-CoV-2-infected individuals up to 217 days after diagnosis, demonstrating that 85% develop and maintain anti-S responses. In a subsample of 64 participants, we further assess anti-Nucleocapsid (N) IgG, neutralizing antibody activity, and T cell responses to Membrane (M), N, and S proteins. In contrast to S-specific antibody responses, anti-N IgG levels decline substantially over time and neutralizing activity toward Delta and Omicron variants is low to non-existent within just weeks of Wildtype SARS-CoV-2 infection. Virus-specific T cells are detectable in most participants, albeit more variable than antibody responses. Cluster analyses of the co-evolution of antibody and T cell responses within individuals identify five distinct trajectories characterized by specific immune patterns and clinical factors. These findings demonstrate the relevant heterogeneity in humoral and cellular immunity to SARS-CoV-2 while also identifying consistent patterns where antibody and T cell responses may work in a compensatory manner to provide protection.
Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Neutralizantes , Anticorpos Antivirais , Humanos , Imunidade Celular , Imunidade Humoral , Imunoglobulina G , Glicoproteína da Espícula de CoronavírusRESUMO
Herpesvirus infections shape the human natural killer (NK) cell compartment. While Epstein-Barr virus (EBV) expands immature NKG2A+ NK cells, human cytomegalovirus (CMV) drives accumulation of adaptive NKG2C+ NK cells. Kaposi sarcoma-associated herpesvirus (KSHV) is a close relative of EBV, and both are associated with lymphomas, including primary effusion lymphoma (PEL), which nearly always harbors both viruses. In this study, KSHV dual infection of mice with reconstituted human immune system components leads to the accumulation of CD56-CD16+CD38+CXCR6+ NK cells. CD56-CD16+ NK cells were also more frequently found in KSHV-seropositive Kenyan children. This NK cell subset is poorly cytotoxic against otherwise-NK-cell-susceptible and antibody-opsonized targets. Accordingly, NK cell depletion does not significantly alter KSHV infection in humanized mice. These data suggest that KSHV might escape NK-cell-mediated immune control by driving CD56-CD16+ NK cell differentiation.
Assuntos
Infecções por Vírus Epstein-Barr/imunologia , Herpesvirus Humano 8/patogenicidade , Células Matadoras Naturais/imunologia , Animais , Diferenciação Celular , Humanos , CamundongosRESUMO
Post-transplant lymphoproliferative disorder (PTLD) is a rare but potentially life-threatening complication, frequently associated with Epstein-Barr virus (EBV), which develops after solid organ or stem cell transplantation. Immunosuppression received by transplant recipients has a significant impact on the development of PTLD by suppressing the function of T cells. The preferential proliferation of NKG2A-positive natural killer (NK) cells during primary symptomatic EBV infection known as infectious mononucleosis (IM) and their reactivity toward EBV-infected B cells point to a role of NK cell in the immune control of EBV. However, NK cell-mediated immune response to EBV in immunosuppressed transplant recipients who develop PTLD remains unclear. In this study, we longitudinally analyzed the phenotype and function of different NK cell subsets in a cohort of pediatric liver transplant patients who develop PTLD and compared them to those of children with IM. We found persistently elevated plasma EBV DNA levels in the PTLD patients indicating suboptimal anti-viral immune control. PTLD patients had markedly decreased frequency of CD56dimNKG2A+Killer Immunoglobulin-like receptor (KIR)- NK cells from the time of diagnosis through remission compared to those of IM patients. Whilst the proliferation of CD56dimNKG2A+KIR- NK cells was diminished in PTLD patients, this NK cell subset maintained its ability to potently degranulate against EBV-infected B cells. Compared to cytomegalovirus (CMV)-seropositive and -negative IM patients, PTLD patients co-infected with CMV and EBV had significantly higher levels of a CMV-associated CD56dimNKG2ChiCD57+NKG2A-KIR+ NK cell subset accumulating at the expense of NKG2A+KIR- NK cells. Taken together, our data indicate that co-infection of CMV and EBV diminishes the frequency of CD56dimNKG2A+KIR- NK cells and contributes to suboptimal control of EBV in immunosuppressed children with PTLD.
Assuntos
Coinfecção , Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/imunologia , Citomegalovirus , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/imunologia , Herpesvirus Humano 4 , Células Matadoras Naturais/imunologia , Fatores Etários , Degranulação Celular/imunologia , Linhagem Celular , Pré-Escolar , Citomegalovirus/imunologia , Infecções por Citomegalovirus/virologia , Suscetibilidade a Doenças , Infecções por Vírus Epstein-Barr/virologia , Feminino , Herpesvirus Humano 4/imunologia , Humanos , Hospedeiro Imunocomprometido , Imunofenotipagem , Terapia de Imunossupressão , Imunossupressores/administração & dosagem , Imunossupressores/farmacocinética , Lactente , Células Matadoras Naturais/metabolismo , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/metabolismo , Transtornos Linfoproliferativos/etiologia , Masculino , Transplante de Órgãos/efeitos adversos , Receptores KIR/metabolismo , Fatores de Tempo , Carga ViralRESUMO
HIV and EBV are human pathogens that cause a considerable burden to worldwide health. In combination, these viruses are linked to AIDS-associated lymphomas. We found that EBV, which transforms B cells, renders them susceptible to HIV-1 infection in a CXCR4 and CD4-dependent manner in vitro and that CXCR4-tropic HIV-1 integrates into the genome of these B cells with the same molecular profile as in autologous CD4+ T cells. In addition, we established a humanized mouse model to investigate the in vivo interactions of EBV and HIV-1 upon coinfection. The respective mice that reconstitute human immune system components upon transplantation with CD34+ human hematopoietic progenitor cells could recapitulate aspects of EBV and HIV immunobiology observed in dual-infected patients. Upon coinfection of humanized mice, EBV/HIV dual-infected B cells could be detected, but were susceptible to CD8+ T-cell-mediated immune control.
Assuntos
Infecções por HIV/imunologia , Infecções por HIV/virologia , Herpesvirus Humano 4/patogenicidade , Animais , Linfócitos B/metabolismo , Linfócitos B/patologia , Linfócitos B/virologia , Antígenos CD4/imunologia , Antígenos CD4/metabolismo , Coinfecção , Modelos Animais de Doenças , Suscetibilidade a Doenças/metabolismo , Suscetibilidade a Doenças/virologia , Infecções por Vírus Epstein-Barr/imunologia , Infecções por HIV/genética , Soropositividade para HIV , HIV-1/metabolismo , HIV-1/patogenicidade , Células-Tronco Hematopoéticas/patologia , Herpesvirus Humano 4/imunologia , Herpesvirus Humano 4/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Receptores CXCR4/metabolismo , Receptores CXCR4/fisiologia , Linfócitos T/imunologiaRESUMO
Epstein-Barr virus (EBV) and Kaposi sarcoma-associated herpesvirus (KSHV) comprise the oncogenic human γ-herpesvirus family and are responsible for 2-3% of all tumours in man. With their prominent growth-transforming abilities and high prevalence in the human population, these pathogens have probably shaped the human immune system throughout evolution for near perfect immune control of the respective chronic infections in the vast majority of healthy pathogen carriers. The exclusive tropism of EBV and KSHV for humans has, however, made it difficult in the past to study their infection, tumourigenesis and immune control in vivo. Mice with reconstituted human immune system components (humanized mice) support replication of both viruses with both persisting latent and productive lytic infection. Moreover, B-cell lymphomas can be induced by EBV alone and KSHV co-infection with gene expression hallmarks of human malignancies that are associated with both viruses. Furthermore, cell-mediated immune control by primarily cytotoxic lymphocytes is induced upon infection and can be probed for its functional characteristics as well as putative requirements for its priming. Insights that have been gained from this model and remaining questions will be discussed in this review. This article is part of the theme issue 'Silent cancer agents: multi-disciplinary modelling of human DNA oncoviruses'.
Assuntos
Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/fisiologia , Herpesvirus Humano 8/fisiologia , Sarcoma de Kaposi/virologia , Animais , Modelos Animais de Doenças , Infecções por Vírus Epstein-Barr/imunologia , Humanos , Camundongos , Camundongos Transgênicos , Sarcoma de Kaposi/imunologiaRESUMO
The type I interferon (IFN) system plays an important role in controlling herpesvirus infections, but it is unclear which IFN-mediated effectors interfere with herpesvirus replication. Here we report that human myxovirus resistance protein B (MxB, also designated Mx2) is a potent human herpesvirus restriction factor in the context of IFN. We demonstrate that ectopic MxB expression restricts a range of herpesviruses from the Alphaherpesvirinae and Gammaherpesvirinae, including herpes simplex virus 1 and 2 (HSV-1 and HSV-2), and Kaposi's sarcoma-associated herpesvirus (KSHV). MxB restriction of HSV-1 and HSV-2 requires GTPase function, in contrast to restriction of lentiviruses. MxB inhibits the delivery of incoming HSV-1 DNA to the nucleus and the appearance of empty capsids, but not the capsid delivery to the cytoplasm or tegument dissociation from the capsid. Our study identifies MxB as a potent pan-herpesvirus restriction factor which blocks the uncoating of viral DNA from the incoming viral capsid.
Assuntos
Infecções por Herpesviridae/imunologia , Herpesviridae/fisiologia , Interferon Tipo I/imunologia , Proteínas de Resistência a Myxovirus/imunologia , Replicação Viral/imunologia , Capsídeo/imunologia , Proteínas do Capsídeo/imunologia , Linhagem Celular Tumoral , Núcleo Celular/imunologia , Núcleo Celular/virologia , Citoplasma , DNA Viral/imunologia , Células HEK293 , Herpesviridae/patogenicidade , Infecções por Herpesviridae/virologia , Humanos , Proteínas de Resistência a Myxovirus/genética , RNA Interferente Pequeno/metabolismo , Desenvelopamento do Vírus/imunologiaRESUMO
The human tumor viruses Epstein-Barr virus (EBV) and Kaposi sarcoma-associated herpesvirus (KSHV) establish persistent infections in B cells. KSHV is linked to primary effusion lymphoma (PEL), and 90% of PELs also contain EBV. Studies on persistent KSHV infection in vivo and the role of EBV co-infection in PEL development have been hampered by the absence of small animal models. We developed mice reconstituted with human immune system components as a model for KSHV infection and find that EBV/KSHV dual infection enhanced KSHV persistence and tumorigenesis. Dual-infected cells displayed a plasma cell-like gene expression pattern similar to PELs. KSHV persisted in EBV-transformed B cells and was associated with lytic EBV gene expression, resulting in increased tumor formation. Evidence of elevated lytic EBV replication was also found in EBV/KSHV dually infected lymphoproliferative disorders in humans. Our data suggest that KSHV augments EBV-associated tumorigenesis via stimulation of lytic EBV replication.