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Successful efforts to activate T cells capable of recognizing weak cancer-associated self-antigens have employed altered peptide antigens to activate T cell responses capable of cross-reacting on native tumor-associated self. A limitation of this approach is the requirement for detailed knowledge about the altered self-peptide ligands used in these vaccines. In the current study we considered allorecognition as an approach for activating CTL capable of recognizing weak or self-antigens in the context of self-MHC. Nonself antigen-presenting molecules typically contain polymorphisms that influence interactions with the bound peptide and TCR interface. Recognition of these nonself structures results in peptide-dependent alloimmunity. Alloreactive T cells target their inducing alloantigens as well as third-party alloantigens but generally fail to target self-antigens. Certain residues located on the alpha-1/2 domains of class I antigen-presenting molecules primarily interface with TCR. These residues are more conserved within and across species than are residues that determine peptide antigen binding properties. Class I variants designed with amino acid substitutions at key positions within the conserved helical structures are shown to provide strong activating signals to alloreactive CD8 T cells while avoiding changes in naturally bound peptide ligands. Importantly, CTL activated in this manner can break self-tolerance by reacting to self-peptides presented by native MHC. The ability to activate self-tolerant T cells capable of cross-reacting on self-peptide-MHC in vivo represents an approach for inducing autoimmunity, with possible application in cancer vaccines.
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Apresentação de Antígeno/imunologia , Citotoxicidade Imunológica , Antígenos de Histocompatibilidade Classe I/imunologia , Linfócitos T Citotóxicos/imunologia , Sequência de Aminoácidos/genética , Animais , Linfócitos T CD8-Positivos/imunologia , Humanos , Tolerância Imunológica , Ligantes , Ativação Linfocitária/imunologia , Camundongos , Peptídeos/genética , Peptídeos/imunologia , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologiaRESUMO
B-cell activation is increasingly linked to numerous fibrotic lung diseases, and it is well known that aggregates of lymphocytes form in the lung of many of these patients. Activation of B-cells by pattern recognition receptors (PRRs) drives the release of inflammatory cytokines, chemokines, and metalloproteases important in the pathophysiology of pulmonary fibrosis. However, the specific mechanisms of B-cell activation in patients with idiopathic pulmonary fibrosis (IPF) are poorly understood. Herein, we have demonstrated that B-cell activation by microbial antigens contributes to the inflammatory and profibrotic milieu seen in patients with IPF. B-cell stimulation by CpG and ß-glucan via PRRs resulted in activation of mTOR-dependent and independent pathways. Moreover, we showed that the B-cell-secreted inflammatory milieu is specific to the inducing antigen and causes differential fibroblast migration and activation. B-cell responses to infectious agents and subsequent B-cell-mediated fibroblast activation are modifiable by antifibrotics, but each seems to exert a specific and different effect. These results suggest that, upon PRR activation by microbial antigens, B-cells can contribute to the inflammatory and fibrotic changes seen in patients with IPF, and antifibrotics are able to at least partially reverse these responses.
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Linfócitos B/imunologia , Movimento Celular , Fibroblastos/patologia , Fibrose Pulmonar Idiopática/imunologia , Fibrose Pulmonar Idiopática/patologia , Antígenos/metabolismo , Linfócitos B/efeitos dos fármacos , Agregação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Humanos , Indóis/farmacologia , Mediadores da Inflamação/metabolismo , Interleucina-6/metabolismo , Pneumonia/patologia , Piridonas/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Quinases da Família src/metabolismoRESUMO
Human immunity exhibits remarkable heterogeneity among individuals, which engenders variable responses to immune perturbations in human populations. Population studies reveal that, in addition to interindividual heterogeneity, systemic immune signatures display longitudinal stability within individuals, and these signatures may reliably dictate how given individuals respond to immune perturbations. We hypothesize that analyzing relationships among these signatures at the population level may uncover baseline immune phenotypes that correspond with response outcomes to immune stimuli. To test this, we quantified global gene expression in peripheral blood CD4+ cells from healthy individuals at baseline and following CD3/CD28 stimulation at two time points 1 mo apart. Systemic CD4+ cell baseline and poststimulation molecular immune response signatures (MIRS) were defined by identifying genes expressed at levels that were stable between time points within individuals and differential among individuals in each state. Iterative differential gene expression analyses between all possible phenotypic groupings of at least three individuals using the baseline and stimulated MIRS gene sets revealed shared baseline and response phenotypic groupings, indicating the baseline MIRS contained determinants of immune responsiveness. Furthermore, significant numbers of shared phenotype-defining sets of determinants were identified in baseline data across independent healthy cohorts. Combining the cohorts and repeating the analyses resulted in identification of over 6000 baseline immune phenotypic groups, implying that the MIRS concept may be useful in many immune perturbation contexts. These findings demonstrate that patterns in complex gene expression variability can be used to define immune phenotypes and discover determinants of immune responsiveness.
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Linfócitos T CD4-Positivos/imunologia , Expressão Gênica/genética , Ativação Linfocitária/imunologia , Transcriptoma/genética , Antígenos CD28/imunologia , Complexo CD3/imunologia , Expressão Gênica/imunologia , Humanos , Ativação Linfocitária/genética , Fenótipo , Transcriptoma/imunologiaRESUMO
RNA sequencing (RNA-seq) has become the widely preferred choice for surveying the genome-wide transcriptome complexity in many organisms. However, the broad adaptation of this methodology into the clinic still needs further evaluation of potential effect of sample preparation factors on its analytical reliability using patient samples. In this study, we examined the impact of three major sample preparation factors (i.e., cDNA library storage time, the quantity of input RNA, and cryopreservation of cell samples) on sequence biases, gene expression profiles, and enriched biological functions using RNAs isolated from primary B cell and CD4+ cell blood samples of healthy subjects. Our comprehensive comparison results suggested that different cDNA library storage time, quantity of input RNA, and cryopreservation of cell samples did not significantly alter gene transcriptional expression profiles generated by RNA-seq experiments. These findings shed new lights on the potential applications of RNA-seq technique to patient samples in a regular clinical setting.
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Perfilação da Expressão Gênica , Biblioteca Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de RNA , Transcriptoma , HumanosRESUMO
RATIONALE: Most immunocompetent patients diagnosed with latent tuberculosis infection (LTBI) will not progress to tuberculosis (TB) reactivation. However, current diagnostic tools cannot reliably distinguish nonprogressing from progressing patients a priori, and thus LTBI therapy must be prescribed with suboptimal patient specificity. We hypothesized that LTBI diagnostics could be improved by generating immunomarker profiles capable of categorizing distinct patient subsets by a combinatorial immunoassay approach. OBJECTIVES: A combinatorial immunoassay analysis was applied to identify potential immunomarker combinations that distinguish among unexposed subjects, untreated patients with LTBI, and treated patients with LTBI and to differentiate risk of reactivation. METHODS: IFN-γ release assay (IGRA) was combined with a flow cytometric assay that detects induction of CD25(+)CD134(+) coexpression on TB antigen-stimulated T cells from peripheral blood. The combinatorial immunoassay analysis was based on receiver operating characteristic curves, technical cut-offs, 95% bivariate normal density ellipse prediction, and statistical analysis. Risk of reactivation was estimated with a prediction formula. MEASUREMENTS AND MAIN RESULTS: Sixty-five out of 150 subjects were included. The combinatorial immunoassay approach identified at least four different T-cell subsets. The representation of these immune phenotypes was more heterogeneous in untreated patients with LTBI than in treated patients with LTBI or unexposed groups. Patients with IGRA(+) CD4(+)CD25(+)CD134(+) T-cell phenotypes had the highest estimated reactivation risk (4.11 ± 2.11%). CONCLUSIONS: These findings suggest that immune phenotypes defined by combinatorial assays may potentially have a role in identifying those at risk of developing TB; this potential role is supported by risk of reactivation modeling. Prospective studies will be needed to test this novel approach.
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Linfócitos T CD4-Positivos/imunologia , Imunocompetência/imunologia , Testes de Liberação de Interferon-gama , Tuberculose Latente/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Estudos de Coortes , Feminino , Citometria de Fluxo , Humanos , Imunoensaio , Subunidade alfa de Receptor de Interleucina-2/imunologia , Masculino , Pessoa de Meia-Idade , Curva ROC , Receptores OX40/imunologia , Medição de Risco , Linfócitos T/imunologia , Adulto JovemRESUMO
Melanoma patients exhibit changes in immune responsiveness in the local tumor environment, draining lymph nodes, and peripheral blood. Immune-targeting therapies are revolutionizing melanoma patient care increasingly, and studies show that patients derive clinical benefit from these newer agents. Nonetheless, predicting which patients will benefit from these costly therapies remains a challenge. In an effort to capture individual differences in immune responsiveness, we are analyzing patterns of gene expression in human peripheral blood cells using RNAseq. Focusing on CD4+ peripheral blood cells, we describe multiple categories of immune regulating genes, which are expressed in highly ordered patterns shared by cohorts of healthy subjects and stage IV melanoma patients. Despite displaying conservation in overall transcriptome structure, CD4+ peripheral blood cells from melanoma patients differ quantitatively from healthy subjects in the expression of more than 2000 genes. Moreover, 1300 differentially expressed genes are found in transcript response patterns following activation of CD4+ cells ex vivo, suggesting that widespread functional discrepancies differentiate the immune systems of healthy subjects and melanoma patients. While our analysis reveals that the transcriptome architecture characteristic of healthy subjects is maintained in cancer patients, the genes expressed differentially among individuals and across cohorts provide opportunities for understanding variable immune states as well as response potentials, thus establishing a foundation for predicting individual responses to stimuli such as immunotherapeutic agents.
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Linfócitos T CD4-Positivos/metabolismo , Perfilação da Expressão Gênica , Melanoma/imunologia , Adulto , Antígenos CD28/fisiologia , Feminino , Humanos , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Receptores de Antígenos de Linfócitos T/fisiologia , Análise de Sequência de RNA , Transdução de SinaisRESUMO
Clinical prediction of nontuberculous mycobacteria lung disease (NTM-LD) progression remains challenging. We aimed to evaluate antigen-specific immunoprofiling utilizing flow cytometry (FC) of activation-induced markers (AIM) and IFN-γ enzyme-linked immune absorbent spot assay (ELISpot) accurately identifies patients with NTM-LD, and differentiate those with progressive from nonprogressive NTM-LD. A Prospective, single-center, and laboratory technician-blinded pilot study was conducted to evaluate the FC and ELISpot based immunoprofiling in patients with NTM-LD (n = 18) and controls (n = 22). Among 18 NTM-LD patients, 10 NTM-LD patients were classified into nonprogressive, and 8 as progressive NTM-LD based on clinical and radiological features. Peripheral blood mononuclear cells were collected from patients with NTM-LD and control subjects with negative QuantiFERON results. After stimulation with purified protein derivative (PPD), mycobacteria-specific peptide pools (MTB300, RD1-peptides), and control antigens, we performed IFN-γ ELISpot and FC AIM assays to access their diagnostic accuracies by receiver operating curve (ROC) analysis across study groups. Patients with NTM-LD had significantly higher percentage of CD4+/CD8+ T-cells co-expressing CD25+CD134+ in response to PPD stimulation, differentiating between NTM-LD and controls. Among patients with NTM-LD, there was a significant difference in CD25+CD134+ co-expression in MTB300-stimulated CD8+ T-cells (p <0.05; AUC-ROC = 0.831; Sensitivity = 75% [95% CI: 34.9-96.8]; Specificity = 90% [95% CI: 55.5-99.7]) between progressors and nonprogressors. Significant differences in the ratios of antigen-specific IFN-γ ELISpot responses were also seen for RD1-nil/PPD-nil and RD1-nil/anti-CD3-nil between patients with nonprogressive vs. progressive NTM-LD. Our results suggest that multiparameter immunoprofiling can accurately identify patients with NTM-LD and may identify patients at risk of disease progression. A larger longitudinal study is needed to further evaluate this novel immunoprofiling approach.
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Infecções por Mycobacterium não Tuberculosas , Pneumonia , Humanos , Projetos Piloto , Estudos Prospectivos , Leucócitos Mononucleares , Infecções por Mycobacterium não Tuberculosas/microbiologia , Micobactérias não TuberculosasRESUMO
Optimal detection strategies for effective convalescent immunity after SARS-CoV-2 infection and vaccination remain unclear. The objective of this study was to characterize convalescent immunity targeting the SARS-CoV-2 spike protein using a multiparametric approach. At the beginning of the pandemic, between April 23, 2020, to May 11, 2020, we recruited 30 COVID-19 unvaccinated convalescent donors and 7 unexposed asymptomatic donors. Peripheral blood mononuclear cells (PBMCs) were obtained from leukapheresis cones. The humoral immune response was assessed by measuring serum anti-SARS-CoV-2 spike S1 subunit IgG semiquantitative ELISA and T cell immunity against S1 and S2 subunits were studied by IFN-γ Enzyme-Linked Immune absorbent Spot (ELISpot), flow cytometric (FC) activation-induced marker (AIM) assays and the assessment of cytotoxic CD8+ T-cell function (in the subset of HLA-A2 positive patients). No single immunoassay was sufficient in identifying anti-spike convalescent immunity among all patients. There was no consistent correlation between adaptive humoral and cellular anti-spike responses. Our data indicate that the magnitude of anti-spike convalescent humoral and cellular immunity is highly heterogeneous and highlights the need for using multiple assays to comprehensively measure SARS-CoV-2 convalescent immunity. These observations might have implications for COVID-19 surveillance, and optimal vaccination strategies for emerging variants. Further studies are needed to determine the optimal assessment of adaptive humoral and cellular immunity following SARSCoV-2 infection, especially in the context of emerging variants and unclear vaccination schedules.
RESUMO
The optimal detection strategies for effective convalescent immunity after SARS-CoV-2 infection and vaccination remain unclear. The objective of this study was to characterize convalescent immunity targeting the SARS-CoV-2 spike protein using a multiparametric approach. At the beginning of the pandemic, we recruited 30 unvaccinated convalescent donors who had previously been infected with COVID-19 and 7 unexposed asymptomatic controls. Peripheral blood mononuclear cells (PBMCs) were obtained from leukapheresis cones. The humoral immune response was assessed by measuring serum anti-SARS-CoV-2 spike S1 subunit IgG via semiquantitative ELISA, and T-cell immunity against S1 and S2 subunits were studied via IFN-γ enzyme-linked immunosorbent spot (ELISpot) and flow cytometric (FC) activation-induced marker (AIM) assays and the assessment of cytotoxic CD8+ T-cell function (in the subset of HLA-A2-positive patients). No single immunoassay was sufficient in identifying anti-spike convalescent immunity among all patients. There was no consistent correlation between adaptive humoral and cellular anti-spike responses. Our data indicate that the magnitude of anti-spike convalescent humoral and cellular immunity is highly heterogeneous and highlights the need for using multiple assays to comprehensively measure SARS-CoV-2 convalescent immunity. These observations might have implications for COVID-19 surveillance, and the determination of optimal vaccination strategies for emerging variants. Further studies are needed to determine the optimal assessment of adaptive humoral and cellular immunity following SARS-CoV-2 infection, especially in the context of emerging variants and unclear vaccination schedules.
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Humoral vaccine responses are known to be suboptimal in patients receiving B-cell targeted therapy, and little is known about vaccine induced T-cell immunity in these patients. In this study, we characterized humoral and cellular antigen-specific anti-SARS-CoV2 responses following COVID-19 vaccination in patients with ANCA-associated vasculitis (AAV) receiving anti-CD20 therapy, who were either B-cell depleted, or B-cell recovered at the time of vaccination and in normal control subjects. SARS-CoV-2 anti-spike (S) and anti-nucleocapsid (NC) antibodies were measured using electrochemiluminescence immunoassays, while SARS-CoV-2 specific T-cell responses to S glycoprotein subunits 1 (S1) and 2 (S2) and receptor binding domain peptide pools were measured using interferon-gamma enzyme-linked immunosorbent spot (ELISPOT) assays. In total, 26 recently vaccinated subjects were studied. Despite the lack of a measurable humoral immune response, B-cell depleted patients mounted a similar vaccine induced antigen-specific T-cell response compared to B-cell recovered patients and normal controls. Our data indicate that to assure a humoral response in patients receiving anti-CD20 therapy, SARS-CoV-2 vaccination should ideally be delayed until B-cell recovery (CD-20 positive B-cells > 10/µl). Nevertheless, SARS-CoV-2 vaccination elicits robust, potentially protective cellular immune responses in these subjects. Further research to characterize the durability and protective effect of vaccine-induced anti-SARS-CoV-2 specific T-cell immunity are needed.
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Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/tratamento farmacológico , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Hospedeiro Imunocomprometido , Rituximab/uso terapêutico , Adulto , Idoso , COVID-19/prevenção & controle , Feminino , Humanos , Fatores Imunológicos/uso terapêutico , Masculino , Pessoa de Meia-Idade , SARS-CoV-2RESUMO
Most gene-based severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines are nonreplicating vectors. They deliver the gene or messenger RNA to the cell to express the spike protein but do not replicate to amplify antigen production. This study tested the utility of replication in a vaccine by comparing replication-defective adenovirus (RD-Ad) and replicating single-cycle adenovirus (SC-Ad) vaccines that express the SARS-CoV-2 spike protein. SC-Ad produced 100 times more spike protein than RD-Ad and generated significantly higher antibodies against the spike protein than RD-Ad after single immunization of Ad-permissive hamsters. SC-Ad-generated antibodies climbed over 14 weeks after single immunization and persisted for more than 10 months. When the hamsters were challenged 10.5 months after single immunization, a single intranasal or intramuscular immunization with SC-Ad-Spike reduced SARS-CoV-2 viral loads and damage in the lungs and preserved body weight better than vaccination with RD-Ad-Spike. This demonstrates the utility of harnessing replication in vaccines to amplify protection against infectious diseases.
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Lymphocyte differentiation from naive CD4(+) T cells into mature Th1, Th2, Th17, or T regulatory cell (Treg) phenotypes has been considered end stage in character. In this study, we demonstrate that dendritic cells (DCs) activated with a novel immune modulator B7-DC XAb (DC(XAb)) can reprogram Tregs into T effector cells. Down-regulation of FoxP3 expression after either in vitro or in vivo Treg-DC(XAb) interaction is Ag-specific, IL-6-dependent, and results in the functional reprogramming of the mature T cell phenotype. The reprogrammed Tregs cease to express IL-10 and TGFbeta, fail to suppress T cell responses, and gain the ability to produce IFN-gamma, IL-17, and TNF-alpha. The ability of IL-6(+) DC(XAb) and the inability of IL-6(-/-) DC(XAb) vaccines to protect animals from lethal melanoma suggest that exogenously modulated DC can reprogram host Tregs. In support of this hypothesis and as a test for Ag specificity, transfer of DC(XAb) into RIP-OVA mice causes a break in immune tolerance, inducing diabetes. Conversely, adoptive transfer of reprogrammed Tregs but not similarly treated CD25(-) T cells into naive RIP-OVA mice is also sufficient to cause autoimmune diabetes. Yet, treatment of normal mice with B7-DC XAb fails to elicit generalized autoimmunity. The finding that mature Tregs can be reprogrammed into competent effector cells provides new insights into the plasticity of T cell lineage, underscores the importance of DC-T cell interaction in balancing immunity with tolerance, points to Tregs as a reservoir of autoimmune effectors, and defines a new approach for breaking tolerance to self Ags as a strategy for cancer immunotherapy.
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Anticorpos/farmacologia , Autoimunidade/efeitos dos fármacos , Antígeno B7-1/imunologia , Fatores de Transcrição Forkhead , Interleucina-17/biossíntese , Linfócitos T Reguladores/citologia , Animais , Comunicação Celular/imunologia , Citocinas/biossíntese , Células Dendríticas/imunologia , Tolerância Imunológica , Camundongos , Mieloma Múltiplo/terapia , Proteína 2 Ligante de Morte Celular Programada 1 , Especificidade do Receptor de Antígeno de Linfócitos T , Linfócitos T Reguladores/imunologia , VacinasRESUMO
Cells within tumors vary in phenotype as a result of changes in gene expression caused by a variety of mechanisms, permitting cancers to evolve under selective pressures from immune and other homeostatic processes. Earlier, we traced apparent losses in heterozygosity (LOH) of spontaneous breast tumors from first generation (F1) intercrossed mice to atypical epigenetic modifications in the structure of DNA across the tumor genomes. Here, we describe a parallel pattern of LOH in gene expression, revealed through quantitation of parental alleles across a population of clonal tumors. We found variegated patterns of LOH, based on allelic ratio outliers in hundreds of genes, enriched in regulatory pathways typically co-opted by tumors. The frequency of outliers was correlated with transcriptional repression of a large set of homozygous genes. These findings suggest stochastic losses in gene expression across the genome of tumors generate phenotypic variation among cells, allowing clonal selection during tumor development.
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Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Homeostase , Neoplasias Mamárias Animais/genética , Processos Estocásticos , Alelos , Animais , Cruzamentos Genéticos , Epigênese Genética , Feminino , Mutação em Linhagem Germinativa , Cariotipagem , Perda de Heterozigosidade , Masculino , Neoplasias Mamárias Animais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Mitose , Fenótipo , Análise de Sequência de RNARESUMO
INTRODUCTION: Malignant pleural mesothelioma is a disease primarily associated with exposure to the carcinogen asbestos. Whereas other carcinogen-related tumors are associated with a high tumor mutation burden, mesothelioma is not. We sought to resolve this discrepancy. METHODS: We used mate-pair (n = 22), RNA (n = 28), and T cell receptor sequencing along with in silico predictions and immunologic assays to understand how structural variants of chromosomes affect the transcriptome. RESULTS: We observed that inter- or intrachromosomal rearrangements were present in every specimen and were frequently in a pattern of chromoanagenesis such as chromoplexy or chromothripsis. Transcription of rearrangement-related junctions was predicted to result in many potential neoantigens, some of which were proven to bind patient-specific major histocompatibility complex molecules and to expand intratumoral T cell clones. T cells responsive to these predicted neoantigens were also present in a patient's circulating T cell repertoire. Analysis of genomic array data from the mesothelioma cohort in The Cancer Genome Atlas suggested that multiple chromothriptic-like events negatively impact survival. CONCLUSIONS: Our findings represent the discovery of potential neoantigen expression driven by structural chromosomal rearrangements. These results may have implications for the development of novel immunotherapeutic strategies and the selection of patients to receive immunotherapies.
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Antígenos/genética , Cromotripsia , Mesotelioma/genética , Neoplasias Pleurais/genética , Transcriptoma/genética , Seleção Clonal Mediada por Antígeno , Simulação por Computador , DNA de Neoplasias/análise , Dosagem de Genes , Rearranjo Gênico , Genômica , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Humanos , Linfócitos do Interstício Tumoral , Mesotelioma/patologia , Peptídeos/genética , Peptídeos/imunologia , Neoplasias Pleurais/patologia , Receptores de Antígenos de Linfócitos T/genética , Análise de Sequência de DNA/métodos , Análise de Sequência de RNA , Taxa de Sobrevida , Linfócitos T/imunologiaRESUMO
Genome-wide identification and characterization of long noncoding RNAs (lncRNA) in individual immune cell lineages helps us better understand the driving mechanisms behind melanoma and advance personalized patient treatment. To elucidate the transcriptional landscape in diverse immune cell types of peripheral blood cells (PBC) in stage IV melanoma, we used whole transcriptome RNA sequencing to profile lncRNAs in CD4+, CD8+, and CD14+ PBC from 132 patient samples. Our integrative computational approach identified 27,625 expressed lncRNAs, 2,744 of which were novel. Both T cells (i.e., CD4+ and CD8+ PBC) and monocytes (i.e., CD14+ PBC) exhibited differential transcriptional expression profiles between patients with melanoma and healthy subjects. Cis- and trans-level coexpression analysis suggested that lncRNAs are potentially involved in many important immune-related pathways and the programmed cell death receptor 1 checkpoint pathways. We also identified nine gene coexpression modules significantly associated with melanoma status, all of which were significantly enriched for three mRNA translation processes. Age and melanoma traits closely correlated with each other, implying that melanoma contains age-associated immune changes. Our computational prediction analysis suggests that many cis- and trans-regulatory lncRNAs could interact with multiple transcriptional and posttranscriptional regulatory elements in CD4+, CD8+, and CD14+ PBC, respectively. These results provide novel insights into the regulatory mechanisms involving lncRNAs in individual immune cell types in melanoma and can help expedite cell type-specific immunotherapy treatments for such diseases.Significance: These findings elucidate melanoma-associated changes to the noncoding transcriptional landscape of distinct immune cell classes, thus providing cell type-specific guidance to targeted immunotherapy regimens. Cancer Res; 78(15); 4411-23. ©2018 AACR.
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Genoma/genética , Melanoma/genética , RNA Longo não Codificante/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/genética , Redes Reguladoras de Genes/genética , Humanos , Monócitos/fisiologia , Linfócitos T/fisiologia , Transcrição Gênica/genética , Transcriptoma/genéticaRESUMO
While bivalent antibodies can block ligand-receptor interactions, IgM pentamers efficiently cross-link cell surface targets and evoke physiological responses. We have described one such interaction between an IgM antibody (Ab) and the B7-DC costimulatory molecule expressed by dendritic cells that induces strong antitumor immunity and modulates pathogenic responses associated with allergic asthma. Progressive changes in gene expression in dendritic cells activated by an IgM B7-DC cross-linking Ab resulted in the increased expression in 350 genes and decreased expression of more than 200 genes over the course of 24 h following Ab treatment. In particular, up-regulation of the caspase inhibitor FLIP and the chemokine receptor CCR7, and the down-regulation of the CXCR4 receptor provide a mechanistic basis of Ab-induced survival and enhanced migration into draining lymph nodes. Increased expression of both cell surface and secreted molecules known to be mediators of the immunomodulatory properties of dendritic cells was detected at both the levels of RNA and protein expression. This analysis documents the ability of IgM Ab to activate a gene expression cascade leading to important biological changes in cellular function and provides mechanistic insight into the potent immunomodulatory properties attributed to this Ab.
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Anticorpos/farmacologia , Antígeno B7-1/farmacologia , Dendritos/fisiologia , Regulação da Expressão Gênica , Imunoglobulina M/imunologia , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/imunologia , Primers do DNA , Dendritos/efeitos dos fármacos , Dendritos/imunologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Análise de Sequência com Séries de Oligonucleotídeos , Proteína 2 Ligante de Morte Celular Programada 1 , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição GênicaRESUMO
The NLRP3 inflammasome is activated in response to different bacterial, viral, and fungal pathogens and serves as modulator of different pattern recognition receptors signaling pathways. One of the main functions of NLRP3 is to participate in IL-1ß maturation which is important in the host defense against Pneumocystis and other fungal infections. However, dysregulation of NLRP3 and IL-1ß secretion are also implicated in the pathophysiology of many auto-inflammatory disorders. Often time's inflammatory flares are preceded by infectious illnesses questioning the role of infection in autoimmune exacerbations. However, we still do not fully understand the exact role that infection or even colonization plays as a trigger of inflammation. Herein, we investigated the role of NLRP3 in circulating B-lymphocytes following activation with two major microbial antigens (ß-glucan and CpG). NLRP3 was determined essential in two independent B-lymphocytes processes: pro-inflammatory cytokine secretion and antibody regulation. Our results show that the ß-glucan fungal cell wall carbohydrate stimulated B-lymphocytes to secrete IL-1ß in a process partially mediated by Dectin-1 activation via SYK and the transcription factors NF-κB and AP-1. This IL-1ß secretion was regulated by the NLRP3 inflammasome and was dependent on potassium efflux and Caspase-1. Interestingly, B-lymphocytes activated by unmethylated CpG motifs, found in bacterial and fungal DNA, failed to induce IL-1ß. However, B-lymphocyte stimulation by CpG resulted in NLRP3 and Caspase-1 activation and the production and secretion of IgM antibodies. Furthermore, CpG-stimulated IgM secretion, unlike ß-glucan-mediated IL-1ß production, was mediated by the mammalian target of rapamycin (mTOR). Inhibition of NLRP3 and the mTOR pathway in CpG activated B-lymphocytes resulted in impaired IgM secretion suggesting their participation in antibody regulation. In conclusion, this study describes a differential response of NLRP3 to ß-glucan and CpG antigens and identifies the NLRP3 inflammasome of human circulating B-lymphocytes as a modulator of the innate and adaptive immune systems.
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Metalloproteinases (MMPs) contribute to tissue remodeling and acute inflammation not only by degrading extracellular matrix proteins but also by controlling the influx of chemokines through the regulation and shedding of syndecans. B-lymphocytes, in addition to their well-known function as antibody producing cells, participate in the innate immune response by secreting inflammatory cytokines and chemokines. However, there is little information about the role of B-lymphocytes in the regulation of MMPs; consequently, herein we investigated whether activated human circulating B-lymphocytes contributed to the secretion of MMPs. We demonstrate that B-lymphocytes activated by un-methylated CpG motifs, found in bacterial DNA, and ß-glucans, found in the cell wall of fungi, both induced MMP-7. Interestingly, while CpG-stimulated cells activated the mTOR pathway via TLR9 receptor to induced MMP-7, ß-glucan-stimulated cells were mTOR-independent and used Dectin-1 receptor. B-lymphocytes did not seem to have a major role in the secretion of tissue inhibitors of metalloproteinases (TIMPs). However, secreted MMP-7 participated in the shedding of Syndecan-4 from the surface of B-lymphocytes. In conclusion, circulating human B-lymphocytes contribute to the regulation of the innate immune system by participating in the secretion of MMP-7 which in turn is important for the shedding of Syndecan-4 in response to infectious stimuli.