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2.
Nat Commun ; 11(1): 5435, 2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-33116135

RESUMO

Memory B cells (MBCs) are long-lived and produce high-affinity, generally, class-switched antibodies. Here, we use a multiparameter approach involving CD27 to segregate naïve B cells (NBC), IgD+ unswitched (unsw)MBCs and IgG+ or IgA+ class-switched (sw)MBCs from humans of different age, sex and race. Conserved antibody variable gene expression indicates that MBCs emerge through unbiased selection from NBCs. Integrative analyses of mRNAs, miRNAs, lncRNAs, chromatin accessibility and cis-regulatory elements uncover a core mRNA-ncRNA transcriptional signature shared by IgG+ and IgA+ swMBCs and distinct from NBCs, while unswMBCs display a transitional transcriptome. Some swMBC transcriptional signature loci are accessible but not expressed in NBCs. Profiling miRNAs reveals downregulated MIR181, and concomitantly upregulated MIR181 target genes such as RASSF6, TOX, TRERF1, TRPV3 and RORα, in swMBCs. Finally, lncRNAs differentially expressed in swMBCs cluster proximal to the IgH chain locus on chromosome 14. Our findings thus provide new insights into MBC transcriptional programs and epigenetic regulation, opening new investigative avenues on these critical cell elements in human health and disease.


Assuntos
Linfócitos B/imunologia , Memória Imunológica/genética , Adulto , Linfócitos B/classificação , Linfócitos B/metabolismo , Cromatina/genética , Cromatina/imunologia , Regiões Determinantes de Complementaridade , Epigênese Genética , Feminino , Perfilação da Expressão Gênica , Humanos , Switching de Imunoglobulina/genética , Cadeias Pesadas de Imunoglobulinas/genética , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Mutação Puntual , Transdução de Sinais/genética , Fatores de Transcrição/genética , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo , Adulto Jovem
3.
Proc Natl Acad Sci U S A ; 117(40): 24957-24963, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32963096

RESUMO

B lymphocytes acquire self-reactivity as an unavoidable byproduct of antibody gene diversification in the bone marrow and in germinal centers (GCs). Autoreactive B cells emerging from the bone marrow are silenced in a series of well-defined checkpoints, but less is known about how self-reactivity that develops by somatic mutation in GCs is controlled. Here, we report the existence of an apoptosis-dependent tolerance checkpoint in post-GC B cells. Whereas defective GC B cell apoptosis has no measurable effect on autoantibody development, disruption of post-GC apoptosis results in accumulation of autoreactive memory B cells and plasma cells, antinuclear antibody production, and autoimmunity. The data presented shed light on mechanisms that regulate immune tolerance and the development of autoantibodies.


Assuntos
Apoptose/genética , Autoimunidade/genética , Genes de Imunoglobulinas/genética , Tolerância Imunológica/genética , Animais , Anticorpos Antinucleares/imunologia , Apoptose/imunologia , Autoanticorpos/imunologia , Autoimunidade/imunologia , Linfócitos B/imunologia , Genes de Imunoglobulinas/imunologia , Centro Germinativo/imunologia , Humanos , Memória Imunológica/genética , Memória Imunológica/imunologia , Camundongos , Plasmócitos/imunologia
4.
PLoS One ; 15(4): e0231498, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32287290

RESUMO

The Polycomb group (PcG) proteins are chromatin factors underlying the process of transcriptional memory to preserve developmental decisions and keep cellular identities. However, not only developmental signals need to be memorized and thus maintained during the life of an organism. For host protection against pathogens, also a memory of previous exposures to an immunogenic stimulus is crucial to mount a more protective immune response upon re-exposure. The antigen-specific adaptive immunity in vertebrates is an example of such a memory to previous immunogenic stimulation. Recently, adaptive characteristics were also attributed to innate immunity, which was classically seen to lack memory. However, the mechanistic details of an adaptive innate immune response are yet to be fully understood and chromatin-based epigenetic mechanisms seem to play an important role in this phenomenon. Possibly, PcG proteins can contribute to such an epigenetic innate immune memory. In this study, we analyzed whether the PcG system can mediate a transcriptional memory of exposure to lipopolysaccharides (LPS). To this end, various forms of LPS pre-treatment were applied to reporter cells and expression kinetics of PcG target genes were analyzed after a second LPS exposure. Neither single nor multiple LPS pre-treatment affected the induction of endogenous LPS-responsive transcripts upon re-exposure. Altogether, our extensive analyses did not provide any evidence for a PcG system-mediated memory of LPS stimulation.


Assuntos
Memória Imunológica/genética , Proteínas do Grupo Polycomb/genética , Proteínas do Grupo Polycomb/imunologia , Imunidade Adaptativa/genética , Imunidade Adaptativa/imunologia , Animais , Linhagem Celular , Cromatina/genética , Drosophila/imunologia , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Epigênese Genética/genética , Imunidade Inata/genética , Imunidade Inata/imunologia , Memória Imunológica/imunologia , Lipopolissacarídeos/genética , Lipopolissacarídeos/imunologia , Proteínas do Grupo Polycomb/metabolismo
5.
Nat Rev Immunol ; 20(6): 375-388, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32132681

RESUMO

Immune memory is a defining feature of the acquired immune system, but activation of the innate immune system can also result in enhanced responsiveness to subsequent triggers. This process has been termed 'trained immunity', a de facto innate immune memory. Research in the past decade has pointed to the broad benefits of trained immunity for host defence but has also suggested potentially detrimental outcomes in immune-mediated and chronic inflammatory diseases. Here we define 'trained immunity' as a biological process and discuss the innate stimuli and the epigenetic and metabolic reprogramming events that shape the induction of trained immunity.


Assuntos
Imunidade Adaptativa/imunologia , Epigênese Genética/imunologia , Doenças do Sistema Imunitário/imunologia , Sistema Imunitário/imunologia , Imunidade Inata/imunologia , Memória Imunológica/imunologia , Imunidade Adaptativa/genética , Animais , Humanos , Sistema Imunitário/metabolismo , Doenças do Sistema Imunitário/genética , Tolerância Imunológica/genética , Tolerância Imunológica/imunologia , Imunidade Inata/genética , Memória Imunológica/genética , Inflamação/genética , Inflamação/imunologia
6.
Mol Immunol ; 120: 67-73, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32085976

RESUMO

CD8 T cells are among the most vigorous soldiers of the immune system that fight viral infections and cancer. CD8 T cell development, maintenance, activation and differentiation are under the tight control of multiple transcriptional and post-transcriptional networks. Over the last two decades it has become clear that non-coding RNAs (ncRNAs), which consist of microRNAs (miRNAs) and long ncRNAs (lncRNAs), have emerged as global biological regulators. While our understanding of the function of specific miRNAs has increased since the discovery of RNA interference, it is still very limited, and the field of lncRNAs is just starting to blossom. Here we will summarize our knowledge on the role of ncRNAs in CD8 T cell biology, including differentiation into memory and exhausted cells.


Assuntos
Linfócitos T CD8-Positivos/imunologia , RNA não Traduzido/genética , Animais , Linfócitos T CD8-Positivos/citologia , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Regulação da Expressão Gênica , Humanos , Memória Imunológica/genética , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Camundongos , MicroRNAs/genética , MicroRNAs/imunologia , Interferência de RNA , RNA Longo não Codificante/genética , RNA Longo não Codificante/imunologia , RNA não Traduzido/imunologia
7.
Sci Rep ; 10(1): 377, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31941995

RESUMO

Chronic inflammation facilitates tumor progression. We discovered that a subset of non-small cell lung cancer cells underwent a gradually progressing epithelial-to-mesenchymal (EMT) phenotype following a 21-day exposure to IL-1ß, an abundant proinflammatory cytokine in the at-risk for lung cancer pulmonary and the lung tumor microenvironments. Pathway analysis of the gene expression profile and in vitro functional studies revealed that the EMT and EMT-associated phenotypes, including enhanced cell invasion, PD-L1 upregulation, and chemoresistance, were sustained in the absence of continuous IL-1ß exposure. We referred to this phenomenon as EMT memory. Utilizing a doxycycline-controlled SLUG expression system, we found that high expression of the transcription factor SLUG was indispensable for the establishment of EMT memory. High SLUG expression in tumors of lung cancer patients was associated with poor survival. Chemical or genetic inhibition of SLUG upregulation prevented EMT following the acute IL-1ß exposure but did not reverse EMT memory. Chromatin immunoprecipitation and methylation-specific PCR further revealed a SLUG-mediated temporal regulation of epigenetic modifications, including accumulation of H3K27, H3K9, and DNA methylation, in the CDH1 (E-cadherin) promoter following the chronic IL-1ß exposure. Chemical inhibition of DNA methylation not only restored E-cadherin expression in EMT memory, but also primed cells for chemotherapy-induced apoptosis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Epigênese Genética , Transição Epitelial-Mesenquimal , Memória Imunológica/imunologia , Inflamação/imunologia , Interleucina-1beta/metabolismo , Antígenos CD/genética , Antígenos CD/metabolismo , Caderinas/genética , Caderinas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/imunologia , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Humanos , Memória Imunológica/genética , Inflamação/genética , Interleucina-1beta/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Fenótipo , Células Tumorais Cultivadas
8.
Nat Immunol ; 21(3): 309-320, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31953534

RESUMO

Tissue-resident memory T cells (TRM cells) are critical for cellular immunity to respiratory pathogens and reside in both the airways and the interstitium. In the present study, we found that the airway environment drove transcriptional and epigenetic changes that specifically regulated the cytolytic functions of airway TRM cells and promoted apoptosis due to amino acid starvation and activation of the integrated stress response. Comparison of airway TRM cells and splenic effector-memory T cells transferred into the airways indicated that the environment was necessary to activate these pathways, but did not induce TRM cell lineage reprogramming. Importantly, activation of the integrated stress response was reversed in airway TRM cells placed in a nutrient-rich environment. Our data defined the genetic programs of distinct lung TRM cell populations and show that local environmental cues altered airway TRM cells to limit cytolytic function and promote cell death, which ultimately leads to fewer TRM cells in the lung.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Reprogramação Celular/genética , Reprogramação Celular/imunologia , Epigênese Genética/imunologia , Memória Imunológica/genética , Pulmão/imunologia , Animais , Apoptose/imunologia , Linfócitos T CD8-Positivos/citologia , Sobrevivência Celular/genética , Sobrevivência Celular/imunologia , Microambiente Celular/genética , Microambiente Celular/imunologia , Feminino , Pulmão/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/patologia
9.
Curr Opin Cell Biol ; 63: 68-75, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31991317

RESUMO

The epigenetic and functional reprogramming of immune genes during induction of trained immunity is accompanied by the metabolic rewiring of cellular state. This memory is induced in the hematopoietic niche and propagated to daughter cells, generating epigenetically and metabolically reprogrammed innate immune cells that are greatly enhanced in their capacity to resolve inflammation. In particular, these cells show accumulation of H3K4me3 and H3K27Ac epigenetic marks on multiple immune gene promoters and associated enhancers. However, the mechanism governing how these epigenetic marks accumulate at discrete immune gene loci has been poorly understood, until now. Here, we discuss some recent advances in the regulation of trained immunity, with a particular focus on the mechanistic role of a novel class of long non-coding RNAs in the establishment of epigenetic marks on trained immune gene promoters.


Assuntos
Epigenômica/métodos , Imunidade Inata/genética , Memória Imunológica/genética , Humanos
10.
New Phytol ; 225(1): 310-325, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31469917

RESUMO

Systemic acquired resistance (SAR) prepares infected plants for faster and stronger defense activation upon subsequent attacks. SAR requires an information relay from primary infection to distal tissue and the initiation and maintenance of a self-maintaining phytohormone salicylic acid (SA)-defense loop. In spatial and temporal resolution, we show that calcium-dependent protein kinase CPK5 contributes to immunity and SAR. In local basal resistance, CPK5 functions upstream of SA synthesis, perception, and signaling. In systemic tissue, CPK5 signaling leads to accumulation of SAR-inducing metabolite N-hydroxy-L-pipecolic acid (NHP) and SAR marker genes, including Systemic Acquired Resistance Deficient 1 (SARD1) Plants of increased CPK5, but not CPK6, signaling display an 'enhanced SAR' phenotype towards a secondary bacterial infection. In the sard1-1 background, CPK5-mediated basal resistance is still mounted, but NHP concentration is reduced and enhanced SAR is lost. The biochemical analysis estimated CPK5 half maximal kinase activity for calcium, K50 [Ca2+ ], to be c. 100 nM, close to the cytoplasmic resting level. This low threshold uniquely qualifies CPK5 to decode subtle changes in calcium, a prerequisite to signal relay and onset and maintenance of priming at later time points in distal tissue. Our data explain why CPK5 functions as a hub in basal and systemic plant immunity.


Assuntos
Proteínas de Arabidopsis/metabolismo , Sinalização do Cálcio , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Resistência à Doença/imunologia , Memória Imunológica , Ácidos Pipecólicos/metabolismo , Doenças das Plantas/imunologia , Imunidade Vegetal , Ácido Salicílico/metabolismo , Cálcio/metabolismo , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Memória Imunológica/genética , Doenças das Plantas/genética , Imunidade Vegetal/genética
11.
Dev Comp Immunol ; 103: 103498, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31525382

RESUMO

The phenomena of enhanced protection of innate immunity responding to a pre-exposed pathogen have been reported in invertebrates. The underpinning molecular basis and mechanism for the enhanced immune protection are still missing. In order to explore the possible molecular basis for enhanced immune protection in molluscs, the transcriptomic analysis of oysters Crassostrea gigas hemocytes after twice stimulation of Vibrio splendidus were conducted, and a total of 403 M clean reads and 34254 differentially expressed genes (DEGs) were collected. There were 2964 common DEGs up-regulated in hemocytes after both the first and second immune stimulation, which were mostly enriched in metabolic processes and immune related pathways, such as endocytosis, MAPK signaling pathway and TLR signal pathway. Moreover, 187 and 55 DEGs were higher expressed at resting (0 h after stimulation) and activating state (12 h after stimulation) of the second immune response than that of the first response, respectively, mainly including immune recognition receptor scavenger receptor 2, signal molecule MAPK2, immune regulator IL17-d, apoptosis inhibitor IAP and effector cathepsin. More importantly, 13 DEGs were long-lastingly higher expressed at both the resting and activating state within the second immune response than that of the first, including TLR signal molecule MyD88, anti-virulent tissue inhibitor of metalloproteinase, anti-bacterial proline-rich transmembrane protein, which might play indispensable roles in enhanced immune protection against V. splendidus re-infection. The expression patterns of TLR signals (CgTLR6 and CgMyD88) and effector molecules (CgTIMP and CgPRTP) were further validated by RT-PCR, which were consistent to transcriptomic results. All the results provided an overall molecular basis of enhanced immune protection for hemocytes defensing against the second stimulation of V. splendidus in oyster, which would be valuable for understanding the protection mechanisms of pre-exposure in invertebrates.


Assuntos
Antibacterianos/imunologia , Crassostrea/imunologia , Transdução de Sinais/imunologia , Vibrio/fisiologia , Animais , Crassostrea/microbiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/imunologia , Hemócitos/metabolismo , Hemócitos/microbiologia , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata/genética , Memória Imunológica/genética , Transdução de Sinais/genética , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo
12.
Cell Rep ; 29(12): 3916-3932.e5, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31851923

RESUMO

Non-recirculating tissue-resident memory T cells (TRMs) are the predominant T cell subset in diverse tissue sites, where they mediate protective immune responses in situ. Here, we reveal a role for TRM in maintaining immune homeostasis in the human pancreas through interactions with resident macrophages and the PD-1/PD-L1 inhibitory pathway. Using tissues obtained from organ donors, we identify that pancreas T cells comprise CD8+PD-1hi TRMs, which are phenotypically, functionally, and transcriptionally distinct compared to TRMs in neighboring jejunum and lymph node sites. Pancreas TRMs cluster with resident macrophages throughout the exocrine areas; TRM effector functions are enhanced by macrophage-derived co-stimulation and attenuated by the PD-1/PD-L1 pathways. Conversely, in samples from chronic pancreatitis, TRMs exhibit reduced PD-1 expression and reduced interactions with macrophages. These findings suggest important roles for PD-1 and TRM-macrophage interactions in controlling tissue homeostasis and immune dysfunctions underlying inflammatory disease, with important implications for PD-1-based immunotherapies.


Assuntos
Antígeno B7-H1/metabolismo , Memória Imunológica/fisiologia , Pâncreas/metabolismo , Pancreatite/imunologia , Pancreatite/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Subpopulações de Linfócitos T/metabolismo , Antígeno B7-H1/genética , Antígenos CD58/metabolismo , Humanos , Imunidade nas Mucosas/genética , Imunidade nas Mucosas/fisiologia , Memória Imunológica/genética , Macrófagos/imunologia , Macrófagos/metabolismo , Pâncreas/imunologia , Pâncreas/patologia , Pancreatite/genética , Receptor de Morte Celular Programada 1/genética , Transdução de Sinais , Subpopulações de Linfócitos T/imunologia
13.
J Virol ; 94(1)2019 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-31619550

RESUMO

The major obstacle to human immunodeficiency type 1 virus (HIV-1) eradication is a reservoir of latently infected cells that persists despite long-term antiretroviral therapy (ART) and is maintained through cellular proliferation. Long-lived memory CD4+ T cells with high self-renewal capacity, such as central memory (CM) T cells and stem cell memory (SCM) T cells, are major contributors to the viral reservoir in HIV-infected individuals on ART. The Wnt/ß-catenin signaling pathway regulates the balance between self-renewal and differentiation of SCM and CM T cells, and pharmacological manipulation of this pathway offers an opportunity to interfere with the proliferation of latently infected cells. Here, we evaluated in vivo a novel approach to inhibit self-renewal of SCM and CM CD4+ T cells in the rhesus macaque (RM) model of simian immunodeficiency (SIV) infection. We used an inhibitor of the Wnt/ß-catenin pathway, PRI-724, that blocks the interaction between the coactivator CREB-binding protein (CBP) and ß-catenin, resulting in the cell fate decision to differentiate rather than proliferate. Our study shows that PRI-724 treatment of ART-suppressed SIVmac251-infected RMs resulted in decreased proliferation of SCM and CM T cells and modified the SCM and CM CD4+ T cell transcriptome toward a profile of more differentiated memory T cells. However, short-term treatment with PRI-724 alone did not significantly reduce the size of the viral reservoir. This work demonstrates for the first time that stemness pathways of long-lived memory CD4+ T cells can be pharmacologically modulated in vivo, thus establishing a novel strategy to target HIV persistence.IMPORTANCE Long-lasting CD4+ T cell subsets, such as central memory and stem cell memory CD4+ T cells, represent critical reservoirs for human immunodeficiency virus (HIV) persistence despite suppressive antiretroviral therapy. These cells possess stem cell-like properties of enhanced self-renewal/proliferation, and proliferation of latently infected memory CD4+ T cells plays a key role in maintaining the reservoir over time. Here, we evaluated an innovative strategy targeting the proliferation of long-lived memory CD4+ T cells to reduce viral reservoir stability. Using the rhesus macaque model, we tested a pharmacological inhibitor of the Wnt/ß-catenin signaling pathway that regulates T cell proliferation. Our study shows that administration of the inhibitor PRI-724 decreased the proliferation of SCM and CM CD4+ T cells and promoted a transcriptome enriched in differentiation genes. Although the viral reservoir size was not significantly reduced by PRI-724 treatment alone, we demonstrate the potential to pharmacologically modulate the proliferation of memory CD4+ T cells as a strategy to limit HIV persistence.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Memória Imunológica/efeitos dos fármacos , Pirimidinonas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Animais , Terapia Antirretroviral de Alta Atividade/métodos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Proteína de Ligação a CREB/antagonistas & inibidores , Proteína de Ligação a CREB/genética , Proteína de Ligação a CREB/imunologia , Diferenciação Celular/efeitos dos fármacos , DNA Viral/antagonistas & inibidores , DNA Viral/genética , DNA Viral/imunologia , Emtricitabina/farmacologia , Feminino , Regulação da Expressão Gênica , Compostos Heterocíclicos com 3 Anéis/farmacologia , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Memória Imunológica/genética , Macaca mulatta , Masculino , Oxazinas , Piperazinas , Piridonas , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/genética , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/patologia , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Vírus da Imunodeficiência Símia/imunologia , Vírus da Imunodeficiência Símia/patogenicidade , Células-Tronco/efeitos dos fármacos , Células-Tronco/imunologia , Células-Tronco/virologia , Tenofovir/farmacologia , Carga Viral/efeitos dos fármacos , Latência Viral , Replicação Viral/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/antagonistas & inibidores , beta Catenina/genética , beta Catenina/imunologia
14.
Front Immunol ; 10: 2159, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31616409

RESUMO

Recently developed molecular methods allow large-scale profiling of T-cell receptor (TCR) sequences that encode for antigen specificity and immunological memory of these cells. However, it is well-known that the even unperturbed TCR repertoire structure is extremely complex due to the high diversity of TCR rearrangements and multiple biases imprinted by VDJ rearrangement process. The latter gives rise to the phenomenon of "public" TCR clonotypes that can be shared across multiple individuals and non-trivial structure of the TCR similarity network. Here, we outline a framework for TCR sequencing data analysis that can control for these biases in order to infer TCRs that are involved in response to antigens of interest. We apply two previously published methods, ALICE and TCRNET, to detect groups of homologous TCRs that are enriched in samples of interest. Using an example dataset of donors with known HLA haplotype and CMV status, we demonstrate that by applying HLA restriction rules and matching against a database of TCRs with known antigen specificity, it is possible to robustly detect motifs of epitope-specific responses in individual repertoires. We also highlight potential shortcomings of TCR clustering methods and demonstrate that highly expanded TCRs should be individually assessed to get the full picture of antigen-specific response.


Assuntos
Antígenos/genética , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/imunologia , Antígenos/imunologia , Análise por Conglomerados , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Haplótipos/genética , Haplótipos/imunologia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Memória Imunológica/genética , Memória Imunológica/imunologia , Anotação de Sequência Molecular/métodos , Recombinação V(D)J/genética , Recombinação V(D)J/imunologia
15.
Front Immunol ; 10: 2262, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31608063

RESUMO

Wiskott-Aldrich syndrome (WAS) is a rare X-linked primary immunodeficiency characterized by recurrent infections, micro thrombocytopenia, eczema, and a high incidence of autoimmunity and malignancy. A defect in the T cell compartment is thought to be a major cause of immunodeficiency in patients with WAS; However, whether the antigen specific T memory cell is altered has not been extensively studied. Here, we examined the expansion/contraction kinetics of CD8+ memory T cells and their maintenance in WASp-/- mice. The results showed that WAS protein (WASp) is not required for differentiation of CD8+ effector T cells; however, CD8+ T cells from WASp-/- mice were hyperactive, resulting in increased cytokine production. The number of CD8+ T memory cells decreased as mice aged, and CD8+ T cell recall responses and protective immunity were impaired. WASp-deficient CD8+ T cells in bone marrow chimeric mice underwent clonal expansion, but the resulting effector cells failed to survive and differentiate into CD8+ memory T cells. Taken together, these findings indicate that WASp plays an intrinsic role in differentiation of CD8+ memory T cells.


Assuntos
Apoptose/imunologia , Linfócitos T CD8-Positivos/imunologia , Memória Imunológica/imunologia , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico/imunologia , Proteína da Síndrome de Wiskott-Aldrich/imunologia , Animais , Apoptose/genética , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/virologia , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Proliferação de Células/genética , Citocinas/imunologia , Citocinas/metabolismo , Humanos , Memória Imunológica/genética , Coriomeningite Linfocítica/genética , Coriomeningite Linfocítica/imunologia , Coriomeningite Linfocítica/virologia , Vírus da Coriomeningite Linfocítica/imunologia , Vírus da Coriomeningite Linfocítica/fisiologia , Camundongos , Camundongos Knockout , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Proteína da Síndrome de Wiskott-Aldrich/genética , Proteína da Síndrome de Wiskott-Aldrich/metabolismo
16.
PLoS Pathog ; 15(9): e1007974, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31536608

RESUMO

Plasmodium relapses are attributed to the activation of dormant liver-stage parasites and are responsible for a significant number of recurring malaria blood-stage infections. While characteristic of human infections caused by P. vivax and P. ovale, their relative contribution to malaria disease burden and transmission remains poorly understood. This is largely because it is difficult to identify 'bona fide' relapse infections due to ongoing transmission in most endemic areas. Here, we use the P. cynomolgi-rhesus macaque model of relapsing malaria to demonstrate that clinical immunity can form after a single sporozoite-initiated blood-stage infection and prevent illness during relapses and homologous reinfections. By integrating data from whole blood RNA-sequencing, flow cytometry, P. cynomolgi-specific ELISAs, and opsonic phagocytosis assays, we demonstrate that this immunity is associated with a rapid recall response by memory B cells that expand and produce anti-parasite IgG1 that can mediate parasite clearance of relapsing parasites. The reduction in parasitemia during relapses was mirrored by a reduction in the total number of circulating gametocytes, but importantly, the cumulative proportion of gametocytes increased during relapses. Overall, this study reveals that P. cynomolgi relapse infections can be clinically silent in macaques due to rapid memory B cell responses that help to clear asexual-stage parasites but still carry gametocytes.


Assuntos
Imunidade Humoral , Malária/imunologia , Malária/parasitologia , Plasmodium cynomolgi/imunologia , Plasmodium cynomolgi/patogenicidade , Animais , Anticorpos Antiprotozoários/sangue , Linfócitos B/imunologia , Perfilação da Expressão Gênica , Interações Hospedeiro-Parasita/genética , Interações Hospedeiro-Parasita/imunologia , Humanos , Imunidade Humoral/genética , Imunoglobulina G/sangue , Memória Imunológica/genética , Macaca mulatta , Malária/genética , Malária Vivax/genética , Malária Vivax/imunologia , Malária Vivax/parasitologia , Masculino , Parasitemia/genética , Parasitemia/imunologia , Parasitemia/parasitologia , Plasmodium vivax/imunologia , Plasmodium vivax/patogenicidade , Recidiva , Esporozoítos/imunologia , Esporozoítos/patogenicidade
17.
Eur Heart J ; 40(48): 3924-3933, 2019 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-31365073

RESUMO

AIMS: A persistent cardiac T-cell response initiated by myocardial infarction is linked to subsequent adverse ventricular remodelling and progression of heart failure. No data exist on T-cell receptor (TCR) repertoire changes in combination with phenotypic characterization of T cells in ischaemic failing human hearts. METHODS AND RESULTS: Analysis of TCR repertoire with high-throughput sequencing revealed that compared with T cells in control hearts, those in ischaemic failing hearts showed a clonally expanded TCR repertoire but similar usage patterns of TRBV-J rearrangements and V gene segments; compared with T cells in peripheral blood, those in ischaemic failing hearts exhibited a restricted and clonally expanded TCR repertoire and different usage patterns of TRBV-J rearrangements and V gene segments, suggesting the occurrence of tissue-specific T-cell expansion in ischaemic failing hearts. Consistently, TCR clonotype sharing was prominent in ischaemic failing hearts, especially in hearts of patients who shared human leucocyte antigen (HLA) alleles. Furthermore, ischaemia heart failure (IHF) heart-associated clonotypes were more frequent in peripheral blood of IHF patients than in that of controls. Heart-infiltrating T cells displayed memory- and effector-like characteristics. Th1 cells were the predominant phenotype among CD4+ T cells; CD8+ T cells were equally as abundant as CD4+ T cells and produced high levels of interferon-γ, granzyme B, and perforin. CONCLUSION: We provide novel evidence for a tissue-specific T-cell response predominated by Th1 cells and cytotoxic CD8+ T cells in ischaemic failing human hearts that may contribute to the progression of heart failure.


Assuntos
Insuficiência Cardíaca/patologia , Infarto do Miocárdio/patologia , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T/patologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Estudos de Casos e Controles , Células Clonais/metabolismo , Progressão da Doença , Granzimas/metabolismo , Insuficiência Cardíaca/metabolismo , Humanos , Memória Imunológica/genética , Interferon gama/metabolismo , Isquemia , Infarto do Miocárdio/metabolismo , Perforina/metabolismo , Fenótipo , Remodelação Ventricular
18.
JCI Insight ; 4(14)2019 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-31341110

RESUMO

Advances in genomic medicine have elucidated an increasing number of genetic etiologies for patients with common variable immunodeficiency (CVID). However, there is heterogeneity in clinical and immunophenotypic presentations and a limited understanding of the underlying pathophysiology of many cases. The primary defects in CVID may extend beyond the adaptive immune system, and the combined defect in both the myeloid and lymphoid compartments suggests the mechanism may involve bone marrow output and earlier progenitors. Using the methylation profile of the human androgen receptor (AR) gene as a surrogate epigenetic marker for bone marrow clonality, we examined the hematopoietic compartments of patients with CVID. Our data show that clonal hematopoiesis is common among patients with adult-onset CVID who do not have associated noninfectious complications. Nonblood tissues did not show a skewed AR methylation status, supporting a model of an acquired clonal hematopoietic event. Attenuation of memory B cell differentiation into long-lived plasma cells (CD20-CD27+CD38+CD138+) was associated with marked changes in the postdifferentiation methylation profile, demonstrating the functional consequence of clonal hematopoiesis on humoral immunity in these patients. This study sheds light on a potential etiology of a subset of patients with CVID, and the findings suggest that it is a stage of an acquired lymphocyte maturation disorder.


Assuntos
Cromossomos Humanos X/genética , Imunodeficiência de Variável Comum/genética , Hematopoese/genética , Memória Imunológica/genética , Inativação do Cromossomo X/imunologia , Adulto , Idoso , Subpopulações de Linfócitos B/imunologia , Estudos de Casos e Controles , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Células Cultivadas , Imunodeficiência de Variável Comum/sangue , Imunodeficiência de Variável Comum/imunologia , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/imunologia , Feminino , Perfilação da Expressão Gênica , Voluntários Saudáveis , Hematopoese/imunologia , Humanos , Imunidade Humoral/genética , Imunofenotipagem , Ativação Linfocitária/genética , Pessoa de Meia-Idade , Cultura Primária de Células , Receptores Androgênicos/genética , Adulto Jovem
19.
Cancer Immunol Res ; 7(9): 1426-1439, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31308016

RESUMO

The adoptive transfer of ex vivo-expanded T cells is a promising approach to treat several malignancies. Several lines of evidence support that the infusion of T cells with early memory features, capable of expanding and persisting after transfer, are associated with better outcomes. We report herein that exposure to exogenous TGFß during human T-cell stimulation ex vivo leads to the accumulation of early/central memory (Tcm) cells. Exposure to TGFß suppressed the expression of BLIMP-1, a key orchestrator of effector T-cell differentiation, and led to the upregulation of the memory-associated transcription factor ID3. Accordingly, this was associated with an early memory transcriptional signature in both CD4+ and CD8+ T-cell subsets. The T cells stimulated in the presence of TGFß expanded normally, and displayed polyfunctional features and no suppressive activity. The adoptive transfer of ex vivo-stimulated T cells into immunodeficient mice confirmed that TGFß-conditioned cells had an enhanced capacity to persist and mediate xenogeneic graft-versus-host disease, as predicted by their early T-cell memory phenotype. Chimeric antigen receptor-expressing T cells generated in the presence of exogenous TGFß were cytotoxic and more effective at controlling tumor growth in immunodeficient animals. This work unveils a new role for TGFß in memory T-cell differentiation and indicates that TGFß signaling may be harnessed to program Tcm differentiation in the context of ex vivo T-cell stimulation for adoptive immunotherapy in humans.


Assuntos
Diferenciação Celular/imunologia , Memória Imunológica , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Apoptose/imunologia , Biomarcadores , Proliferação de Células , Células Cultivadas , Citocinas/metabolismo , Metilação de DNA , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/metabolismo , Humanos , Memória Imunológica/efeitos dos fármacos , Memória Imunológica/genética , Imunomodulação , Imunofenotipagem , Imunoterapia Adotiva/métodos , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Camundongos , Subpopulações de Linfócitos T/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Front Immunol ; 10: 1177, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31191543

RESUMO

The drug targets IL23 and IL12 regulate pathogenicity and plasticity of intestinal Th17 cells in Crohn's disease (CD) and ulcerative colitis (UC), the two most common inflammatory bowel diseases (IBD). However, studies examining Th17 dysregulation in mesenteric lymph nodes (mLNs) of these patients are rare. We showed that in mLNs, CD could be distinguished from UC by increased frequencies of CCR6+CXCR3-RORγ+Tbet-CD4+ (Th17) memory T cells enriched in CD62Llow effector memory T cells (TEM), and their differentially expressed molecular profile. Th17 TEM cells (expressing IL17A, IL17F, RORC, and STAT3) displayed a higher pathogenic/cytotoxic (IL23R, IL18RAP, and GZMB, CD160, PRF1) gene signature in CD relative to UC, while non-pathogenic/regulatory genes (IL9, FOXP3, CTLA4) were more elevated in UC. In both CD and UC, IL12 but not IL23, augmented IFNγ expression in Th17 TEM and switched their molecular profile toward an ex-Th17 (Th1*)-biased transcriptomic signature (increased IFNG, and decreased TCF7, IL17A), suggesting that Th17 plasticity occurs in mLNs before their recruitment to inflamed colon. We propose that differences observed between Th17 cell frequencies and their molecular profile in CD and UC might have implications in understanding disease pathogenesis, and thus, therapeutic management of patients with IBD.


Assuntos
Colite Ulcerativa/imunologia , Doença de Crohn/imunologia , Interleucina-17/imunologia , Linfonodos/imunologia , Células Th17/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/genética , Doença de Crohn/diagnóstico , Doença de Crohn/genética , Citocinas/genética , Citocinas/imunologia , Citocinas/metabolismo , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Memória Imunológica/genética , Memória Imunológica/imunologia , Interleucina-17/genética , Interleucina-17/metabolismo , Linfonodos/metabolismo , Masculino , Mesentério/imunologia , Pessoa de Meia-Idade , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Células Th17/metabolismo , Adulto Jovem
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