RESUMO
Human immunodeficiency virus 1 (HIV-1) infection is characterized by a dynamic and persistent state of viral replication that overwhelms the host immune system in the absence of antiretroviral therapy (ART). The impact of prolonged treatment on the antiviral efficacy of HIV-1-specific CD8+ T cells has nonetheless remained unknown. Here, we used single-cell technologies to address this issue in a cohort of aging individuals infected early during the pandemic and subsequently treated with continuous ART. Our data showed that long-term ART was associated with a process of clonal succession, which effectively rejuvenated HIV-1-specific CD8+ T cell populations in the face of immune senescence. Tracking individual transcriptomes further revealed that initially dominant CD8+ T cell clonotypes displayed signatures of exhaustion and terminal differentiation, whereas newly dominant CD8+ T cell clonotypes displayed signatures of early differentiation and stemness associated with natural control of viral replication. These findings reveal a degree of immune resilience that could inform adjunctive treatments for HIV-1.
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Bovine leukemia virus (BLV) infection results in polyclonal expansion of infected B lymphocytes, and ~5% of infected cattle develop enzootic bovine leukosis (EBL). Since BLV is a retrovirus, each individual clone can be identified by using viral integration sites. To investigate the distribution of tumor cells in EBL cattle, we performed viral integration site analysis by using a viral DNA capture-sequencing method. We found that the same tumor clones existed in peripheral blood, with a dominance similar to that in lymphoma tissue. Additionally, we observed that multiple tumor tissues from different sites harbored the identical clones, indicating that tumor cells can circulate and distribute systematically in EBL cattle. To investigate clonal expansion of BLV-infected cells during a long latent period, we collected peripheral blood samples from asymptomatic cattle every 2 years, among which several cattle developed EBL. We found that no detectable EBL clone existed before the diagnosis of EBL in some cases; in the other cases, clones that were later detected as malignant clones at the EBL stage were present several months or even years before the disease onset. To establish a feasible clonality-based method for the diagnosis of EBL, we simplified a quick and cost-effective method, namely, rapid amplification of integration sites for BLV infection (BLV-RAIS). We found that the clonality values (Cvs) were well correlated between the BLV-RAIS and viral DNA capture-sequencing methods. Furthermore, receiver operating characteristic (ROC) curve analysis identified an optimal Cv cutoff value of 0.4 for EBL diagnosis, with excellent diagnostic sensitivity (94%) and specificity (100%). These results indicated that the RAIS method efficiently and reliably detected expanded clones not only in lymphoma tissue but also in peripheral blood. Overall, our findings elucidated the clonal dynamics of BLV- infected cells during EBL development. In addition, Cvs of BLV-infected cells in blood can be used to establish a valid and noninvasive diagnostic test for potential EBL onset. IMPORTANCE Although BLV has been eradicated in some European countries, BLV is still endemic in other countries, including Japan and the United States. EBL causes huge economic damage to the cattle industry. However, there are no effective drugs or vaccines to control BLV infection and related diseases. The strategy of eradication of infected cattle is not practical due to the high endemicity of BLV. Furthermore, how BLV-infected B cell clones proliferate during oncogenesis and their distribution in EBL cattle have yet to be elucidated. Here, we provided evidence that tumor cells are circulating in the blood of diseased cattle. Thus, the Cv of virus-infected cells in blood is useful information for the evaluation of the disease status. The BLV-RAIS method provides quantitative and accurate clonality information and therefore is a promising method for the diagnosis of EBL.
Assuntos
Leucose Enzoótica Bovina , Vírus da Leucemia Bovina , Animais , Bovinos , Leucose Enzoótica Bovina/diagnóstico , Leucose Enzoótica Bovina/patologia , DNA Viral/genética , Linfócitos B/patologia , Vírus da Leucemia Bovina/genética , Células Clonais/patologiaRESUMO
The immunogenicity of a T cell Ag is correlated with the ability of its antigenic epitope to bind HLA and be stably presented to T cells. This presents a challenge for the development of effective cancer immunotherapies, as many self-derived tumor-associated epitopes elicit weak T cell responses, in part due to weak binding affinity to HLA. Traditional methods to increase peptide-HLA binding affinity involve modifying the peptide to reflect HLA allele binding preferences. Using a different approach, we sought to analyze whether the immunogenicity of wild-type peptides could be altered through modification of the HLA binding pocket. After analyzing HLA class I peptide binding pocket alignments, we identified an alanine 81 to leucine (A81L) modification within the F binding pocket of HLA-A*24:02 that was found to heighten the ability of artificial APCs to retain and present HLA-A*24:02-restricted peptides, resulting in increased T cell responses while retaining Ag specificity. This modification led to increased peptide exchange efficiencies for enhanced detection of low-avidity T cells and, when expressed on artificial APCs, resulted in greater expansion of Ag-specific T cells from melanoma-derived tumor-infiltrating lymphocytes. Our study provides an example of how modifications to the HLA binding pocket can enhance wild-type cognate peptide presentation to heighten T cell activation.
Assuntos
Epitopos de Linfócito T , Peptídeos , Alanina , Antígeno HLA-A2 , Antígeno HLA-A24 , Leucina , Linfócitos TRESUMO
Human T-cell leukemia virus type 1 (HTLV-1) spreads through cell contact. Therefore, this virus persists and propagates within the host by two routes: clonal proliferation of infected cells and de novo infection. The proliferation is influenced by the host immune responses and expression of viral genes. However, the detailed mechanisms that control clonal expansion of infected cells remain to be elucidated. In this study, we show that newly infected clones were strongly suppressed, and then stable clones were selected, in a patient who was infected by live liver transplantation from a seropositive donor. Conversely, most HTLV-1+ clones persisted in patients who received hematopoietic stem cell transplantation from seropositive donors. To clarify the role of cell-mediated immunity in this clonal selection, we suppressed CD8+ or CD16+ cells in simian T-cell leukemia virus type 1 (STLV-1)-infected Japanese macaques. Decreasing CD8+ T cells had marginal effects on proviral load (PVL). However, the clonality of infected cells changed after depletion of CD8+ T cells. Consistent with this, PVL at 24 hours in vitro culture increased, suggesting that infected cells with higher proliferative ability increased. Analyses of provirus in a patient who received Tax-peptide pulsed dendritic cells indicate that enhanced anti-Tax immunity did not result in a decreased PVL although it inhibited recurrence of ATL. We postulate that in vivo selection, due to the immune response, cytopathic effects of HTLV-1 and intrinsic attributes of infected cells, results in the emergence of clones of HTLV-1-infected T cells that proliferate with minimized HTLV-1 antigen expression.
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Células Clonais/virologia , Infecções por HTLV-I/imunologia , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Leucemia-Linfoma de Células T do Adulto/imunologia , Linfócitos T/virologia , Adulto , Animais , Linfócitos T CD8-Positivos/imunologia , Células Clonais/imunologia , Células Dendríticas/imunologia , Feminino , Produtos do Gene tax/imunologia , Infecções por HTLV-I/transmissão , Infecções por HTLV-I/virologia , Transplante de Células-Tronco Hematopoéticas , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Humanos , Leucemia-Linfoma de Células T do Adulto/virologia , Transplante de Fígado/efeitos adversos , Macaca fuscata , Masculino , Pessoa de Meia-Idade , Células T Matadoras Naturais/imunologia , Provírus , Linfócitos T/citologia , Carga Viral , Replicação ViralRESUMO
Human T-cell leukemia virus type 1 (HTLV-1) infects mainly CD4+CCR4+ effector/memory T cells in vivo. However, it remains unknown whether HTLV-1 preferentially infects these T cells or this virus converts infected precursor cells to specialized T cells. Expression of viral genes in vivo is critical to study viral replication and proliferation of infected cells. Therefore, we first analyzed viral gene expression in non-human primates naturally infected with simian T-cell leukemia virus type 1 (STLV-1), whose virological attributes closely resemble those of HTLV-1. Although the tax transcript was detected only in certain tissues, Tax expression was much higher in the bone marrow, indicating the possibility of de novo infection. Furthermore, Tax expression of non-T cells was suspected in bone marrow. These data suggest that HTLV-1 infects hematopoietic cells in the bone marrow. To explore the possibility that HTLV-1 infects hematopoietic stem cells (HSCs), we analyzed integration sites of HTLV-1 provirus in various lineages of hematopoietic cells in patients with HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP) and a HTLV-1 carrier using the high-throughput sequencing method. Identical integration sites were detected in neutrophils, monocytes, B cells, CD8+ T cells and CD4+ T cells, indicating that HTLV-1 infects HSCs in vivo. We also detected Tax protein in myeloperoxidase positive neutrophils. Furthermore, dendritic cells differentiated from HTLV-1 infected monocytes caused de novo infection to T cells, indicating that infected monocytes are implicated in viral spreading in vivo. Certain integration sites were re-detected in neutrophils from HAM/TSP patients at different time points, indicating that infected HSCs persist and differentiate in vivo. This study demonstrates that HTLV-1 infects HSCs, and infected stem cells differentiate into diverse cell lineages. These data indicate that infection of HSCs can contribute to the persistence and spread of HTLV-1 in vivo.
Assuntos
Infecções por HTLV-I/virologia , Células-Tronco Hematopoéticas/virologia , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Animais , Linfócitos T CD8-Positivos/virologia , Células Cultivadas , Produtos do Gene tax/genética , Produtos do Gene tax/metabolismo , Infecções por HTLV-I/imunologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Humanos , Macaca mulatta , Neutrófilos/virologiaRESUMO
Forkhead box transcription factor 3 (FOXP3) plays a pivotal role in the suppressive function of regulatory T cells. In addition to mRNA levels, FOXP3 activity can also be controlled by posttranslational mechanisms, which have not been studied in a comprehensive manner. Through extensive screening using selective inhibitors, we demonstrate that the inhibition of type I protein arginine methytransferases (PRMTs) attenuates the suppressive functions of regulatory T cells. FOXP3 undergoes methylation on arginine residues at positions 48 and 51 by interacting with protein arginine methyltransferase 1 (PRMT1). The inhibition of arginine methylation confers gene expression profiles representing type I helper T cells to FOXP3+ T cells, which results in attenuated suppressive activity. A methylation-defective mutant of FOXP3 displays less potent activity to suppress xenogeneic graft-versus-host disease in vivo. These results elucidate an important role of arginine methylation to enhance FOXP3 functions and are potentially applicable to modulate regulatory T cell functions.
Assuntos
Arginina/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Linfócitos T Reguladores/metabolismo , Animais , Biomarcadores , Linhagem Celular , Citocinas/metabolismo , Modelos Animais de Doenças , Imunofluorescência , Fatores de Transcrição Forkhead/genética , Perfilação da Expressão Gênica , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/metabolismo , Doença Enxerto-Hospedeiro/mortalidade , Humanos , Estimativa de Kaplan-Meier , Masculino , Metilação , Camundongos , Mutação , Processamento de Proteína Pós-Traducional , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Reguladores/imunologiaRESUMO
Recent work has delineated key differences in the antigen processing and presentation mechanisms underlying HLA-DP alleles encoding glycine at position 84 of the DPß chain (DP84GGPM87). These DPs are unable to associate with the class II-associated Ii peptide (CLIP) region of the invariant chain (Ii) chaperone early in the endocytic pathway, leading to continuous presentation of endogenous antigens. However, little is known about the chaperone support involved in the loading of these endogenous antigens onto DP molecules. Here, we demonstrate the proteasome and TAP dependency of this pathway and reveal the ability of HLA class I to compete with DP84GGPM87 for the presentation of endogenous antigens, suggesting that shared subcellular machinery may exist between the two classes of HLA. We identify physical interactions of prototypical class I-associated chaperones with numerous DP alleles, including TAP2, tapasin, ERp57, calnexin, and calreticulin, using a conventional immunoprecipitation and immunoblot approach and confirm the existence of these interactions in vivo through the use of the BioID2 proximal biotinylation system in human cells. Based on immunological assays, we then demonstrate the ability of each of these chaperones to facilitate the presentation of endogenously derived, but not exogenously derived, antigens on DP molecules. Considering previous genetic and clinical studies linking DP84GGPM87 to disease frequency and severity in autoimmune disease, viral infections, and cancer, we suggest that the above chaperones may form the molecular basis of these observable clinical differences through facilitating the presentation of endogenously derived antigens to CD4+ T cells.
Assuntos
Apresentação de Antígeno/imunologia , Antígenos HLA-DP/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Chaperonas Moleculares/imunologia , Membro 3 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/genética , Membro 3 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/imunologia , Antígenos/imunologia , Linfócitos T CD4-Positivos/imunologia , Calnexina/genética , Calnexina/imunologia , Calreticulina/genética , Calreticulina/imunologia , Linhagem Celular , Células HEK293 , Humanos , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/imunologia , Chaperonas Moleculares/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Isomerases de Dissulfetos de Proteínas/genética , Isomerases de Dissulfetos de Proteínas/imunologiaRESUMO
Human T-cell leukemia virus type 1 (HTLV-1) infects CD4+ T cells and induces proliferation of infected cells in vivo, which leads to the onset of adult T-cell leukemia (ATL) in some infected individuals. The HTLV-1 bZIP factor (HBZ) gene, which is encoded in the minus strand of HTLV-1, plays critical roles in pathogenesis. In this study, RNA-seq and ChIP-seq analyses using HBZ transduced T cells revealed that HBZ upregulates the expression and promoter acetylation levels of a co-inhibitory molecule, T cell immunoglobulin and ITIM domain (TIGIT), in addition to those of regulatory T cells related genes, Foxp3 and Ccr4. TIGIT was expressed on CD4+ T cells from HBZ-transgenic (HBZ-Tg) mice, and on ATL cells and HTLV-1 infected CD4+ T cells of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) in vivo. Expression of Blimp1 and IL-10 was upregulated in TIGIT+CD4+ cells of HBZ-Tg mice compared with TIGIT-CD4+ T cells, suggesting the correlation between TIGIT expression and IL-10 production. When CD4+ T cells from HBZ-Tg mice were stimulated with TIGIT's ligand, CD155, their production of the inhibitory cytokine IL-10 was enhanced. Furthermore, dendritic cells from HBZ-Tg mice produced high levels of IL-10 after stimulation. These data suggest that HBZ alters immune system to suppressive state via TIGIT and IL-10. Importantly, TIGIT suppressed T-cell responses to another HTLV-1 virus protein, Tax, in vitro. Blocking of TIGIT and PD-1 slightly increased anti-Tax T-cell activity in some HAM/TSP patients. These results suggest that HBZ-induced TIGIT on HTLV-1 infected cells impairs T-cell responses to viral antigens. This study shows that HBZ-induced TIGIT plays a pivotal role in attenuating host immune responses and shaping a microenvironment favorable to HTLV-1.
Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/imunologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Evasão da Resposta Imune/imunologia , Receptores Imunológicos/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Imunoprecipitação da Cromatina , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Regulação Viral da Expressão Gênica/imunologia , Humanos , Leucemia-Linfoma de Células T do Adulto/virologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Análise de Sequência com Séries de OligonucleotídeosRESUMO
Human T-cell leukemia virus type 1 (HTLV-1) causes adult T-cell leukemia-lymphoma (ATL) and inflammatory diseases in a small percentage of infected individuals. Host immune responses, in particular cytotoxic T lymphocytes (CTLs), influence the proliferation and survival of ATL cells and HTLV-1-infected cells. We generated recombinant vaccinia viruses (rVVs) expressing HTLV-1 basic leucine zipper (bZIP) factor (HBZ) or Tax to study the immunogenic potential of these viral proteins. Vaccination with rVV expressing Tax or HBZ induced specific T-cell responses, although multiple boosters were needed for HBZ. HBZ-stimulated T cells killed HBZ peptide-pulsed T cells and CD4(+) T cells from HBZ transgenic (HBZ-Tg) mice. The anti-lymphoma effect of the CTLs targeting HBZ was tested in mice inoculated with a lymphoma cell line derived from an HBZ-Tg mouse. Transfer of splenocytes from HBZ-immunized mice increased the survival of the lymphoma cell-inoculated mice, suggesting that the anti-HBZ CTLs have a protective effect. The rVV could also induce specific T-cell responses to HBZ and Tax in HTLV-1-infected rhesus monkeys. On the basis of the results of rVV-vaccinated mice and macaques, we identified a candidate peptide (HBZ157-176) for vaccine development. Dendritic cells pulsed with this peptide could generate HBZ-specific CTLs from human CD8(+) T cells. This study demonstrates that HBZ could be a target for immunotherapy of patients with ATL.
Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/imunologia , Produtos do Gene tax/imunologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Leucemia-Linfoma de Células T do Adulto/prevenção & controle , Linfócitos T Citotóxicos/imunologia , Vacinas Sintéticas/imunologia , Proteínas Virais/imunologia , Sequência de Aminoácidos , Animais , Fatores de Transcrição de Zíper de Leucina Básica/química , Linhagem Celular Tumoral , Humanos , Leucemia-Linfoma de Células T do Adulto/imunologia , Leucemia-Linfoma de Células T do Adulto/virologia , Macaca mulatta , Camundongos Endogâmicos C57BL , Camundongos SCID , Dados de Sequência Molecular , Vacinas Sintéticas/química , Vaccinia virus/imunologia , Proteínas Virais/químicaRESUMO
Adult T-cell leukemia (ATL) patients and human T-cell leukemia virus-1 (HTLV-1) infected individuals succumb to opportunistic infections. Cell mediated immunity is impaired, yet the mechanism of this impairment has remained elusive. The HTLV-1 basic leucine zipper factor (HBZ) gene is encoded in the minus strand of the viral DNA and is constitutively expressed in infected cells and ATL cells. To test the hypothesis that HBZ contributes to HTLV-1-associated immunodeficiency, we challenged transgenic mice that express the HBZ gene in CD4 T cells (HBZ-Tg mice) with herpes simplex virus type 2 or Listeria monocytogenes, and evaluated cellular immunity to these pathogens. HBZ-Tg mice were more vulnerable to both infections than non-Tg mice. The acquired immune response phase was specifically suppressed, indicating that cellular immunity was impaired in HBZ-Tg mice. In particular, production of IFN-γ by CD4 T cells was suppressed in HBZ-Tg mice. HBZ suppressed transcription from the IFN-γ gene promoter in a CD4 T cell-intrinsic manner by inhibiting nuclear factor of activated T cells and the activator protein 1 signaling pathway. This study shows that HBZ inhibits CD4 T-cell responses by directly interfering with the host cell-signaling pathway, resulting in impaired cell-mediated immunity in vivo.
Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/fisiologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Citocinas/metabolismo , Imunidade Celular/imunologia , Interferon gama/genética , Células Th1/imunologia , Proteínas Virais/fisiologia , Animais , Linfócitos T CD4-Positivos/metabolismo , Células Cultivadas , Imunoprecipitação da Cromatina , Feminino , Citometria de Fluxo , Regulação da Expressão Gênica , Herpes Simples/imunologia , Herpes Simples/metabolismo , Herpes Simples/virologia , Herpesvirus Humano 2/patogenicidade , Humanos , Interferon gama/metabolismo , Listeria monocytogenes/patogenicidade , Listeriose/imunologia , Listeriose/metabolismo , Listeriose/virologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Regiões Promotoras Genéticas , Proteínas dos Retroviridae , Células Th1/metabolismo , Fator de Transcrição AP-1/metabolismoRESUMO
Determinants of HIV-1 latency establishment are yet to be elucidated. HIV reservoir comprises a rare fraction of infected cells that can survive host and virus-mediated killing. In vitro reporter models so far offered a feasible means to inspect this population, but with limited capabilities to dissect provirus silencing dynamics. Here, we describe a new HIV reporter model, HIV-Timer of cell kinetics and activity (HIV-Tocky) with dual fluorescence spontaneous shifting to reveal provirus silencing and reactivation dynamics. This unique feature allows, for the first time, identifying two latent populations: a directly latent, and a recently silenced subset, with the latter having integration features suggestive of stable latency. Our proposed model can help address the heterogeneous nature of HIV reservoirs and offers new possibilities for evaluating eradication strategies.
Assuntos
Infecções por HIV , Provírus , Humanos , Provírus/genética , Latência Viral/genética , Infecções por HIV/genéticaRESUMO
BACKGROUND: Highly transmissible viruses including SARS-CoV-2 frequently accumulate novel mutations that are detected via high-throughput sequencing. However, there is a need to develop an alternative rapid and non-expensive approach. Here we developed a novel multiplex DNA detection method Intelli-OVI for analysing existing and novel mutations of SARS-CoV-2. METHODS: We have developed Intelli-OVI that includes the micro-disc-based method IntelliPlex and computational algorithms of objective variant identification (OVI). More than 250 SARS-CoV-2 positive samples including wastewater ones were analysed to verify the efficiency of the method. RESULTS: IntelliPlex uses micro-discs printed with a unique pictorial pattern as a labelling conjugate for DNA probes, and OVI allows simultaneous identification of several variants using multidimensional data obtained by the IntelliPlex method. Importantly, de novo mutations can be identified by decreased signals, which indicates that there is an emergence of de novo variant virus as well as prompts the need to design additional primers and probes. We have upgraded probe panel according to the emergence of new variants and demonstrated that Intelli-OVI efficiently identified more than 20 different SARS-CoV-2 variants by using 35 different probes simultaneously. CONCLUSIONS: Intelli-OVI can be upgraded to keep up with rapidly evolving viruses as we showed in this study using SARS-CoV-2 as an example and may be suitable for other viruses but would need to be validated.
As the COVID-19 pandemic progresses, it is increasingly becoming important to be able to detect emerging new variants of concerns of SARS-CoV-2, the virus that causes COVID-19, for accurate surveillance and timely interventions. We developed a rapid diagnostic method for detecting multiple SARS-CoV-2 variants and tested it using various starting materials such as sputum, nasopharyngeal swabs and wastewater. The method could accurately detect multiple subvariants of Omicron and showed potential for rapid adaptability to detect the virus as it evolves. This technology could enable continuous monitoring of emerging SARS-CoV-2 variants and the opportunity to intercept transmission with timely interventions to prevent viral spread.
RESUMO
BACKGROUND: Human T-cell leukemia virus type 1 (HTLV-1) causes chronic infection leading to development of adult T-cell leukemia (ATL) and inflammatory diseases. Non-human primates infected with simian T-cell leukemia virus type 1 (STLV-1) are considered to constitute a suitable animal model for HTLV-1 research. However, the function of the regulatory and accessory genes of STLV-1 has not been analyzed in detail. In this study, STLV-1 in naturally infected Japanese macaques was analyzed. RESULTS: We identified spliced transcripts of STLV-1 corresponding to HTLV-1 tax and HTLV-1 bZIP factor (HBZ). STLV-1 Tax activated the NFAT, AP-1 and NF-κB signaling pathways, whereas STLV-1 bZIP factor (SBZ) suppressed them. Conversely, SBZ enhanced TGF-ß signaling and induced Foxp3 expression. Furthermore, STLV-1 Tax activated the canonical Wnt pathway while SBZ suppressed it. STLV-1 Tax enhanced the viral promoter activity while SBZ suppressed its activation. Then we addressed the clonal proliferation of STLV-1⺠cells by massively sequencing the provirus integration sites. Some clones proliferated distinctively in monkeys with higher STLV-1 proviral loads. Notably, one of the monkeys surveyed in this study developed T-cell lymphoma in the brain; STLV-1 provirus was integrated in the lymphoma cell genome. When anti-CCR4 antibody, mogamulizumab, was administered into STLV-1-infected monkeys, the proviral load decreased dramatically within 2 weeks. We observed that some abundant clones recovered after discontinuation of mogamulizumab administration. CONCLUSIONS: STLV-1 Tax and SBZ have functions similar to those of their counterparts in HTLV-1. This study demonstrates that Japanese macaques naturally infected with STLV-1 resemble HTLV-1 carriers and are a suitable model for the investigation of persistent HTLV-1 infection and asymptomatic HTLV-1 carrier state. Using these animals, we verified that mogamulizumab, which is currently used as a drug for relapsed ATL, is also effective in reducing the proviral load in asymptomatic individuals.
Assuntos
Infecções por Deltaretrovirus/veterinária , Modelos Animais de Doenças , Leucemia de Células T/veterinária , Doenças dos Primatas/patologia , Doenças dos Primatas/virologia , Vírus Linfotrópico T Tipo 1 de Primatas/isolamento & purificação , Infecções Tumorais por Vírus/veterinária , Animais , Infecções por Deltaretrovirus/patologia , Infecções por Deltaretrovirus/virologia , Humanos , Leucemia de Células T/patologia , Leucemia de Células T/virologia , Macaca , Vírus Linfotrópico T Tipo 1 de Primatas/crescimento & desenvolvimento , Vírus Linfotrópico T Tipo 1 de Primatas/patogenicidade , Infecções Tumorais por Vírus/patologia , Infecções Tumorais por Vírus/virologiaRESUMO
Human T-cell leukemia virus type 1 (HTLV-1) is an oncogenic retrovirus that is etiologically associated with adult T-cell leukemia. The HTLV-1 bZIP factor (HBZ), which is encoded by the minus strand of the provirus, is involved in both regulation of viral gene transcription and T-cell proliferation. We showed in this report that HBZ interacted with Smad2/3, and enhanced transforming growth factor-ß (TGF-ß)/Smad transcriptional responses in a p300-dependent manner. The N-terminal LXXLL motif of HBZ was responsible for HBZ-mediated TGF-ß signaling activation. In a serial immunoprecipitation assay, HBZ, Smad3, and p300 formed a ternary complex, and the association between Smad3 and p300 was markedly enhanced in the presence of HBZ. In addition, HBZ could overcome the repression of the TGF-ß response by Tax. Finally, HBZ expression resulted in enhanced transcription of Pdgfb, Sox4, Ctgf, Foxp3, Runx1, and Tsc22d1 genes and suppression of the Id2 gene; such effects were similar to those by TGF-ß. In particular, HBZ induced Foxp3 expression in naive T cells through Smad3-dependent TGF-ß signaling. Our results suggest that HBZ, by enhancing TGF-ß signaling and Foxp3 expression, enables HTLV-1 to convert infected T cells into regulatory T cells, which is thought to be a critical strategy for virus persistence.
Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Proteína p300 Associada a E1A/metabolismo , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Leucemia-Linfoma de Células T do Adulto/virologia , Proteínas Smad Reguladas por Receptor/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Proteínas Virais/metabolismo , Animais , Fatores de Transcrição de Zíper de Leucina Básica/química , Fatores de Transcrição de Zíper de Leucina Básica/genética , Linhagem Celular , Linhagem Celular Tumoral , Fatores de Transcrição Forkhead/genética , Regulação Leucêmica da Expressão Gênica , Regulação Viral da Expressão Gênica , Infecções por HTLV-I/complicações , Humanos , Leucemia-Linfoma de Células T do Adulto/genética , Leucemia-Linfoma de Células T do Adulto/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Terciária de Proteína , Proteínas dos Retroviridae , Transdução de Sinais , Fator de Transcrição AP-1/metabolismo , Proteínas Virais/química , Proteínas Virais/genéticaRESUMO
Human T-cell leukemia virus type-1 (HTLV-1) causes adult T-cell leukemia/lymphoma (ATL). HTLV-1 carriers have a lifelong asymptomatic balance between infected cells and host antiviral immunity; however, 5-10% of carriers lose this balance and develop ATL. Coinfection with Strongyloides promotes ATL development, suggesting that the immunological status of infected individuals is a determinant of HTLV-1 pathogenicity. As CD4+ T cells play a central role in host immunity, the deregulation of their function and differentiation via HTLV-1 promotes the immune evasion of infected T cells. During ATL development, the accumulation of genetic and epigenetic alterations in key host immunity-related genes further disturbs the immunological balance. Various approaches are available for treating these abnormalities; however, hematopoietic stem cell transplantation is currently the only treatment with the potential to cure ATL. The patient's immune state may contribute to the treatment outcome. Additionally, the activity of the anti-CC chemokine receptor 4 antibody, mogamulizumab, depends on immune function, including antibody-dependent cytotoxicity. In this comprehensive review, we summarize the immunopathogenesis of HTLV-1 infection in ATL and discuss the clinical findings that should be considered when developing treatment strategies for ATL.
Assuntos
Vírus Linfotrópico T Tipo 1 Humano , Leucemia-Linfoma de Células T do Adulto , Linfoma , Adulto , Humanos , Vírus Linfotrópico T Tipo 1 Humano/genética , Leucemia-Linfoma de Células T do Adulto/patologia , Linfócitos T CD4-PositivosRESUMO
The gut microbiota has emerged as a key regulator of immune checkpoint inhibitor (ICI) efficacy. Therapeutic approaches aimed at manipulating the microbiota through targeted reconstitution to enhance cancer treatment outcomes have garnered considerable attention. A single live microbial biotherapeutic bacterium, Clostridium butyricum MIYAIRI 588 strain (CBM588), has been shown to enhance the effects of ICI monotherapy in patients with advanced lung cancer. However, whether CBM588 affects the outcomes of chemoimmunotherapy combinations in lung cancer remains unknown. We hypothesized that CBM588 augments the effect of chemoimmunotherapy combinations and restores diminished effectiveness in patients with non-small cell lung cancer (NSCLC) receiving dysbiosis-inducing drugs. To validate this hypothesis, we retrospectively analyzed 106 patients with stage IV or recurrent metastatic NSCLC consecutively treated with chemoimmunotherapy combinations. A survival analysis was performed employing univariate and multivariate Cox proportional hazard models with inverse probability of treatment weighting (IPTW) using propensity scores. Forty-five percent of patients received Clostridium butyricum therapy. CBM588 significantly extended overall survival in patients with NSCLC receiving chemoimmunotherapy. The favorable impact of CBM588 on the efficacy of chemoimmunotherapy combinations varied based on tumor-programmed cell death ligand 1 (PD-L1) expression. The survival benefit of CBM588 in the PD-L1 <1% cohort was higher than that in the PD-L1 1-49% and PD-L1 ≥ 50% cohorts. Furthermore, CBM588 was associated with improved overall survival in patients receiving proton pump inhibitors and/or antibiotics. CBM588-induced manipulation of the commensal microbiota holds the potential to enhance the efficacy of chemoimmunotherapy combinations, warranting further exploration of the synergy between CBM588 and immunotherapy.
RESUMO
Human T-cell leukemia virus type 1 (HTLV-1), a retrovirus which mainly infects CD4+ T cells and causes adult T-cell leukemia/lymphoma (ATL), is primarily transmitted via direct cell-to-cell transmission. This feature generates a wide variety of infected clones in hosts, which are maintained via clonal proliferation, resulting in the persistence and survival of the virus. The maintenance of the pool of infected cells is achieved by sculpting the immunophenotype of infected cells and modulating host immune responses to avoid immune surveillance. Here, we review the processes undertaken by HTLV-1 to modulate and subvert host immune responses which contributes to viral persistence and development of ATL.
Assuntos
Vírus Linfotrópico T Tipo 1 Humano , Leucemia-Linfoma de Células T do Adulto , Adulto , Humanos , Carcinogênese , Imunofenotipagem , Linfócitos TRESUMO
Human T-cell leukemia virus type 1 (HTLV-1) is a retrovirus that causes adult T-cell leukemia/lymphoma (ATL), a cancer of infected CD4+ T-cells. There is both sense and antisense transcription from the integrated provirus. Sense transcription tends to be suppressed, but antisense transcription is constitutively active. Various efforts have been made to elucidate the regulatory mechanism of HTLV-1 provirus for several decades; however, it remains unknown how HTLV-1 antisense transcription is maintained. Here, using proviral DNA-capture sequencing, we found a previously unidentified viral enhancer in the middle of the HTLV-1 provirus. The transcription factors, SRF and ELK-1, play a pivotal role in the activity of this enhancer. Aberrant transcription of genes in the proximity of integration sites was observed in freshly isolated ATL cells. This finding resolves certain long-standing questions concerning HTLV-1 persistence and pathogenesis. We anticipate that the DNA-capture-seq approach can be applied to analyze the regulatory mechanisms of other oncogenic viruses integrated into the host cellular genome.
Assuntos
Vírus Linfotrópico T Tipo 1 Humano , Leucemia-Linfoma de Células T do Adulto , DNA , Vírus Linfotrópico T Tipo 1 Humano/genética , Humanos , Leucemia-Linfoma de Células T do Adulto/genética , Provírus/genética , Sequências Reguladoras de Ácido NucleicoRESUMO
Persistence of HIV-1 latent reservoir cells during antiretroviral therapy (ART) is a major obstacle for curing HIV-1. Even though latency-reversing agents (LRAs) are under development to reactivate and eradicate latently infected cells, there are few useful models for evaluating LRA activity in vitro. Here, we establish a long-term cell culture system called the "widely distributed intact provirus elimination" (WIPE) assay. It harbors thousands of different HIV-1-infected cell clones with a wide distribution of HIV-1 provirus similar to that observed in vivo. Mathematical modeling and experimental results from this in vitro infection model demonstrates that the addition of an LRA to ART shows a latency-reversing effect and contributes to the eradication of replication-competent HIV-1. The WIPE assay can be used to optimize therapeutics against HIV-1 latency and investigate mechanistic insights into the clonal selection of heterogeneous HIV-1-infected cells.
Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Humanos , Provírus/genética , Ativação Viral , Latência Viral , HIV-1/genética , Infecções por HIV/tratamento farmacológicoRESUMO
Human T cell leukemia virus type 1 (HTLV-1) mainly infects CD4+ T cells and induces chronic, persistent infection in infected individuals, with some developing adult T cell leukemia/lymphoma (ATL). HTLV-1 alters cellular differentiation, activation, and survival; however, it is unknown whether and how these changes contribute to the malignant transformation of infected cells. In this study, we used single-cell RNA-sequencing and T cell receptor-sequencing to investigate the differentiation and HTLV-1-mediated transformation of T cells. We analyzed 87,742 PBMCs from 12 infected and 3 uninfected individuals. Using multiple independent bioinformatics methods, we demonstrated the seamless transition of naive T cells into activated T cells, whereby HTLV-1-infected cells in an activated state further transformed into ATL cells, which are characterized as clonally expanded, highly activated T cells. Notably, the greater the activation state of ATL cells, the more they acquire Treg signatures. Intriguingly, the expression of HLA class II genes in HTLV-1-infected cells was uniquely induced by the viral protein Tax and further upregulated in ATL cells. Functional assays revealed that HTLV-1-infected cells upregulated HLA class II molecules and acted as tolerogenic antigen-presenting cells to induce anergy of antigen-specific T cells. In conclusion, our study revealed the in vivo mechanisms of HTLV-1-mediated transformation and immune escape at the single-cell level.