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1.
Artigo em Inglês | MEDLINE | ID: mdl-31919622

RESUMO

Tumor-associated macrophage and T-cell subsets are implicated in the pathogenesis of diffuse large B-cell lymphoma, follicular lymphoma, and classical Hodgkin lymphoma. Macrophages provide essential mechanisms of tumor immune evasion through checkpoint ligand expression and secretion of suppressive cytokines. However, normal and tumor-associated macrophage phenotypes are less well characterized than those of tumor-infiltrating T-cell subsets, and it would be especially valuable to know whether the polarization state of macrophages differs across lymphoma tumor microenvironments. Here, an established mass cytometry panel designed to characterize myeloid-derived suppressor cells and known macrophage maturation and polarization states was applied to characterize B-lymphoma tumors and non-malignant human tissue. High-dimensional single-cell analyses were performed using dimensionality reduction and clustering tools. Phenotypically distinct intra-tumor macrophage subsets were identified based on abnormal marker expression profiles that were associated with lymphoma tumor types. While it had been proposed that measurement of CD163 and CD68 might be sufficient to reveal macrophage subsets in tumors, results here indicated that S100A9, CCR2, CD36, Slan, and CD32 should also be measured to effectively characterize lymphoma-specific tumor macrophages. Additionally, the presence of phenotypically distinct, abnormal macrophage populations was closely linked to the phenotype of intra-tumor T-cell populations, including PD-1 expressing T cells. These results further support the close links between macrophage polarization and T-cell functional state, as well as the rationale for targeting tumor-associated macrophages in cancer immunotherapies.

3.
PLoS Genet ; 15(6): e1007721, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31199803

RESUMO

B-cell activation yields abundant cell death in parallel to clonal amplification and remodeling of immunoglobulin (Ig) genes by activation-induced deaminase (AID). AID promotes affinity maturation of Ig variable regions and class switch recombination (CSR) in mature B lymphocytes. In the IgH locus, these processes are under control of the 3' regulatory region (3'RR) super-enhancer, a region demonstrated in the mouse to be both transcribed and itself targeted by AID-mediated recombination. Alternatively to CSR, IgH deletions joining Sµ to "like-switch" DNA repeats that flank the 3' super-enhancer can thus accomplish so-called "locus suicide recombination" (LSR) in mouse B-cells. Using an optimized LSR-seq high throughput method, we now show that AID-mediated LSR is evolutionarily conserved and also actively occurs in humans, providing an activation-induced cell death pathway in multiple conditions of B-cell activation. LSR either focuses on the functional IgH allele or is bi-allelic, and its signature is mainly detected when LSR is ongoing while it vanishes from fully differentiated plasma cells or from "resting" blood memory B-cells. Highly diversified breakpoints are distributed either within the upstream (3'RR1) or downstream (3'RR2) copies of the IgH 3' super-enhancer and all conditions activating CSR in vitro also seem to trigger LSR although TLR ligation appeared the most efficient. Molecular analysis of breakpoints and junctions confirms that LSR is AID-dependent and reveals junctional sequences somehow similar to CSR junctions but with increased usage of microhomologies.


Assuntos
Linfócitos B/imunologia , Citidina Desaminase/genética , Região de Troca de Imunoglobulinas/genética , Imunoglobulinas/imunologia , Alelos , Animais , Diferenciação Celular/genética , Citidina Desaminase/imunologia , Marcação de Genes , Humanos , Região de Troca de Imunoglobulinas/imunologia , Tecido Linfoide/imunologia , Camundongos , Tonsila Palatina/imunologia , Tonsila Palatina/metabolismo , Plasmócitos/imunologia , Plasmócitos/metabolismo , Receptores de Antígenos de Linfócitos B/genética , Receptores de Antígenos de Linfócitos B/imunologia , Sequências Reguladoras de Ácido Nucleico
4.
Haematologica ; 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31221779

RESUMO

Cell identity relies on the cross-talk between genetics and epigenetics and their impact on gene expression. Oxidation of 5-methylcytosine into 5-hydroxymethylcytosine is the first step of an active DNA demethylation process occurring mainly at enhancers and gene bodies and, as such, participates in processes governing cell identity in normal and pathological conditions. Although genetic alterations are well documented in multiple myeloma, epigenetic alterations associated with this disease have not yet been thoroughly analyzed. To gain insight into the biology of multiple myeloma, genome-wide 5-hydroxymethylcytosine profiles were obtained and showed that regions enriched in this modified base overlap with multiple myeloma enhancers and super enhancers and are close to highly expressed genes. Through the definition of a multiple myeloma-specific 5-hydroxymethylcytosine signature, we identified FAM72D as a poor prognostic gene located on 1q21, a region amplified in high risk myeloma. We further uncovered that FAM72D functions as part of the FOXM1 transcription factor network controlling cell proliferation and survival and evidenced an increased sensitivity of cells expressing high levels of FOXM1 and FAM72 to epigenetic drugs targeting histone deacetylases and DNA methyltransferases.

5.
Leukemia ; 33(6): 1540, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30903015

RESUMO

In the original version of this article the authors noted an omission in the author affiliations where the university details: Queen Mary University of London was not included in the original affiliation for the majority of the authors. The correct affiliations are as follows1. Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, UK3. Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary University of London, London, UK6. Evolution and Cancer Laboratory, Barts Cancer Institute, Queen Mary University of London, London, UK.

6.
Clin Cancer Res ; 25(2): 735-746, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30348636

RESUMO

PURPOSE: Follicular lymphoma arises from a germinal center B-cell proliferation supported by a bidirectional crosstalk with tumor microenvironment, in particular with follicular helper T cells (Tfh). We explored the relation that exists between the differentiation arrest of follicular lymphoma cells and loss-of-function of CREBBP acetyltransferase.Experimental Design: The study used human primary cells obtained from either follicular lymphoma tumors characterized for somatic mutations, or inflamed tonsils for normal germinal center B cells. Transcriptome and functional analyses were done to decipher the B- and T-cell crosstalk. Responses were assessed by flow cytometry and molecular biology including ChIP-qPCR approaches. RESULTS: Conversely to normal B cells, follicular lymphoma cells are unable to upregulate the transcription repressor, PRDM1, required for plasma cell differentiation. This defect occurs although the follicular lymphoma microenvironment is enriched in the potent inducer of PRDM1 and IL21, highly produced by Tfhs. In follicular lymphoma carrying CREBBP loss-of-function mutations, we found a lack of IL21-mediated PRDM1 response associated with an abnormal increased enrichment of the BCL6 protein repressor in PRDM1 gene. Moreover, in these follicular lymphoma cells, pan-HDAC inhibitor, vorinostat, restored their PRDM1 response to IL21 by lowering BCL6 bound to PRDM1. This finding was reinforced by our exploration of patients with follicular lymphoma treated with another pan-HDAC inhibitor. Patients showed an increase of plasma cell identity genes, mainly PRDM1 and XBP1, which underline the progression of follicular lymphoma B cells in the differentiation process. CONCLUSIONS: Our data uncover a new mechanism by which pan-HDAC inhibitors may act positively to treat patients with follicular lymphoma through the induction of the expression of plasma cell genes.

7.
Am J Clin Pathol ; 151(3): 324-327, 2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30383211

RESUMO

Objectives: WBC differentials performed using flow cytometry with monoclonal antibodies have been developed in the last decade and are nowadays integrated into the routine workflow of some laboratories. Definition of reference values for each population is required in order to achieve an automatic validation of the results by laboratory software. Methods: We analyzed 584 samples from three hospitals using the Hematoflow solution to define the reference values. Results: Reference values are presented for five groups according to age (0-5, 6-11, 12-19, 20-69, and >69 years). Conclusions: These normal values will be helpful in the definition of relevant threshold for the automatic validation of samples analyzed by flow cytometry and the flagging of pathologic samples.


Assuntos
Citometria de Fluxo/métodos , Software , Fluxo de Trabalho , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Humanos , Lactente , Contagem de Leucócitos/métodos , Pessoa de Meia-Idade , Valores de Referência , Adulto Jovem
8.
Blood Adv ; 2(15): 1889-1900, 2018 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-30087107

RESUMO

A better characterization of T-cell subsets in the microenvironment of classical Hodgkin lymphoma (cHL) would help to develop immunotherapies. Using multicolor flow cytometry, we identified in 6 of 43 cHL tissue samples a previously unrecognized subset of CD8 T cells coexpressing CXCR5 and inducible T-cell costimulator (ICOS) molecules (CD8CXCR5+ICOS+). These cells shared phenotypic features with follicular helper T (TFH) cells including low CCR7 expression together with high expression of B-cell lymphoma-6, programmed cell death 1, B and T lymphocyte attenuator, CD200, and OX40. They had deficient cytotoxicity, low interferon-γ secretion, and common functional properties with intratumoral CD4+ TFH cells, such as production of interleukin-4 (IL-4), IL-21, CXCL13, and capacity to sustain B cells. Gene profiling analysis showed a significant similarity between the signatures of CD8CXCR5+ICOS+ T cells and CD4+ TFH cells. Benign lymphadenitis tissues (n = 8) were devoid of CD8CXCR5+ICOS+ cells. Among the 35 B-cell lymphoma tissues analyzed, including follicular lymphomas (n = 13), diffuse large cell lymphomas (n = 12), marginal zone lymphomas (MZLs; n = 3), mantle cell lymphomas (n = 3), and chronic lymphocytic leukemias (n = 4), only 1 MZL sample contained CD8CXCR5+ICOS+ cells. Lymphoma tumors with CD8CXCR5+ICOS+ cells shared common histopathological features including residual germinal centers, and contained high amounts of activated CD8CXCR5-ICOS+ cells. These data demonstrate a CD8 T-cell differentiation pathway leading to the acquisition of some TFH similarities. They suggest a particular immunoediting process with global CD8 activation acting mainly, but not exclusively, in HL tumors.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Regulação Neoplásica da Expressão Gênica , Doença de Hodgkin/metabolismo , Proteína Coestimuladora de Linfócitos T Induzíveis/biossíntese , Proteínas de Neoplasias/biossíntese , Receptores CXCR5/biossíntese , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Diferenciação Celular , Citocinas/metabolismo , Feminino , Doença de Hodgkin/patologia , Humanos , Masculino
10.
Blood ; 132(5): 510-520, 2018 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-29871863

RESUMO

Activated B-cell diffuse large B-cell lymphoma (ABC-DLBCL) is an aggressive lymphoproliferative disorder involving chronic NF-κB activation. Several mutations in the BCR and MyD88 signaling pathway components, such as MyD88 L265P, are implicated in this aberrant activation. Among heat shock proteins, HSP110 has recently been identified as a prosurvival and/or proliferation factor in many cancers, but its role in ABC-DLBCL survival mechanisms remained to be established. We observed that short hairpin RNA-mediated HSP110 silencing decreased the survival of several ABC-DLBCL cell lines and decreased immunoglobulin M-MyD88 co-localization and subsequent NF-κB signaling. Conversely, overexpression of HSP110 in ABC-DLBCL or non-DLBCL cell lines increased NF-κB signaling, indicating a tight interplay between HSP110 and the NF-κB pathway. By using immunoprecipitation and proximity ligation assays, we identified an interaction between HSP110 and both wild-type MyD88 and MyD88 L265P. HSP110 stabilized both MyD88 forms with a stronger effect on MyD88 L265P, thus facilitating chronic NF-κB activation. Finally, HSP110 expression was higher in lymph node biopsies from patients with ABC-DLBCL than in normal reactive lymph nodes, and a strong correlation was found between the level of HSP110 and MyD88. In conclusion, we identified HSP110 as a regulator of NF-κB signaling through MyD88 stabilization in ABC-DLBCL. This finding reveals HSP110 as a new potential therapeutic target in ABC-DLBCL.


Assuntos
Proteínas de Choque Térmico HSP110/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Fator 88 de Diferenciação Mieloide/química , NF-kappa B/metabolismo , Estudos de Coortes , Proteínas de Choque Térmico HSP110/genética , Humanos , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/genética , Estabilidade Proteica , Transdução de Sinais , Células Tumorais Cultivadas
11.
Mol Cancer Ther ; 17(8): 1739-1751, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29743205

RESUMO

CD47, an ubiquitously expressed innate immune checkpoint receptor that serves as a universal "don't eat me" signal of phagocytosis, is often upregulated by hematologic and solid cancers to evade immune surveillance. Development of CD47-targeted modalities is hindered by the ubiquitous expression of the target, often leading to rapid drug elimination and hemotoxicity including anemia. To overcome such liabilities, we have developed a fully human bispecific antibody, NI-1701, designed to coengage CD47 and CD19 selectively on B cells. NI-1701 demonstrates favorable elimination kinetics with no deleterious effects seen on hematologic parameters following single or multiple administrations to nonhuman primates. Potent in vitro and in vivo activity is induced by NI-1701 to kill cancer cells across a plethora of B-cell malignancies and control tumor growth in xenograft mouse models. The mechanism affording maximal tumor growth inhibition by NI-1701 is dependent on the coengagement of CD47/CD19 on B cells inducing potent antibody-dependent cellular phagocytosis of the targeted cells. NI-1701-induced control of tumor growth in immunodeficient NOD/SCID mice was more effective than that achieved with the anti-CD20 targeted antibody, rituximab. Interestingly, a synergistic effect was seen when tumor-implanted mice were coadministered NI-1701 and rituximab leading to significantly improved tumor growth inhibition and regression in some animals. We describe herein, a novel bispecific antibody approach aimed at sensitizing B cells to become more readily phagocytosed and eliminated thus offering an alternative or adjunct therapeutic option to patients with B-cell malignancies refractory/resistant to anti-CD20-targeted therapy. Mol Cancer Ther; 17(8); 1739-51. ©2018 AACR.


Assuntos
Anticorpos Biespecíficos/genética , Leucemia/genética , Leucemia/terapia , Linfoma de Células B/genética , Linfoma de Células B/terapia , Animais , Antígenos CD19 , Antígeno CD47 , Humanos , Leucemia/patologia , Linfoma de Células B/patologia , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Blood ; 131(2): 174-181, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29061568

RESUMO

The benefit of radiotherapy (RT) after chemotherapy in limited-stage diffuse large B-cell lymphoma (DLBCL) remains controversial. We conducted a randomized trial in patients with nonbulky limited-stage DLBCL to evaluate the benefit of RT after rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). Patients were stratified according to the modified International Prognostic Index, including lactate dehydrogenase, Eastern Cooperative Oncology Group performance status, age, and disease stage. The patients received 4 or 6 consecutive cycles of R-CHOP delivered once every 2 weeks, followed or not by RT at 40 Gy delivered 4 weeks after the last R-CHOP cycle. All patients were evaluated by fluorodeoxyglucose-positron emission tomography scans performed at baseline, after 4 cycles of R-CHOP, and at the end of treatment. The primary objective of the trial was event-free survival (EFS) from randomization. The trial randomly assigned 165 patients in the R-CHOP arm and 169 in the R-CHOP plus RT arm. In an intent-to-treat analysis with a median follow-up of 64 months, 5-year EFS was not statistically significantly different between the 2 arms, with 89% ± 2.9% in the R-CHOP arm vs 92% ± 2.4% in the R-CHOP plus RT arm (hazard ratio, 0.61; 95% confidence interval [CI], 0.3-1.2; P = .18). Overall survival was also not different at 92% (95% CI, 89.5%-94.5%) for patients assigned to R-CHOP alone and 96% (95% CI, 94.3%-97.7%) for those assigned to R-CHOP plus RT (P = not significant). R-CHOP alone is not inferior to R-CHOP followed by RT in patients with nonbulky limited-stage DLBCL. This trial was registered at www.clinicaltrials.gov as #NCT00841945.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/radioterapia , Anticorpos Monoclonais Murinos/administração & dosagem , Anticorpos Monoclonais Murinos/efeitos adversos , Anticorpos Monoclonais Murinos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Ciclofosfamida/uso terapêutico , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Doxorrubicina/uso terapêutico , Feminino , Humanos , Estimativa de Kaplan-Meier , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Prednisona/uso terapêutico , Intervalo Livre de Progressão , Estudos Prospectivos , Rituximab , Resultado do Tratamento , Vincristina/administração & dosagem , Vincristina/efeitos adversos , Vincristina/uso terapêutico
15.
Nat Commun ; 8(1): 1443, 2017 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-29129929

RESUMO

Plasma cell differentiation is a tightly regulated process that requires appropriate T cell helps to reach the induction threshold. To further understand mechanisms by which T cell inputs regulate B cell fate decision, we investigate the minimal IL-2 stimulation for triggering human plasma cell differentiation in vitro. Here we show that the timed repression of BACH2 through IL-2-mediated ERK/ELK1 signalling pathway directs plasma cell lineage commitment. Enforced BACH2 repression in activated B cells unlocks the plasma cell transcriptional program and induces their differentiation into immunoglobulin M-secreting cells. RNA-seq and ChIP-seq results further identify BACH2 target genes involved in this process. An active regulatory region within the BACH2 super-enhancer, under ELK1 control and differentially regulated upon B-cell activation and cellular divisions, helps integrate IL-2 signal. Our study thus provides insights into the temporal regulation of BACH2 and its targets for controlling the differentiation of human naive B cells.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/antagonistas & inibidores , Diferenciação Celular/imunologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Interleucina-2/imunologia , Plasmócitos/citologia , Proteínas Elk-1 do Domínio ets/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Células Cultivadas , Redes Reguladoras de Genes/imunologia , Humanos , Imunoglobulina M/biossíntese , Imunoglobulina M/imunologia , Ativação Linfocitária/imunologia , Plasmócitos/imunologia , Fator 1 de Ligação ao Domínio I Regulador Positivo/biossíntese , Interferência de RNA , RNA Interferente Pequeno/genética , Transdução de Sinais/imunologia , Linfócitos T/imunologia , Proteína 1 de Ligação a X-Box/biossíntese
16.
Cancer Immunol Immunother ; 66(8): 1103-1111, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28689360

RESUMO

In lymphomas arising from the germinal center, prognostic factors are linked to the myeloid compartment. In particular, high circulating monocyte or myeloid-derived suppressor cell counts are associated with poor prognosis for patients with high-grade B-cell lymphomas. Macrophages with an M2 phenotype are enriched within lymphoma tumors. However, the M1/M2 nomenclature is now deprecated and the clinical impact of this phenotype remains controversial. Across cancer types, myeloid cells are primarily thought to function as immune suppressors during tumor initiation and maintenance, but the biological mechanisms behind the myeloid signatures are still poorly understood in germinal center B-cell lymphomas. Herein, we describe the role and clinical relevance of myeloid cells in B-cell lymphoma and propose innovative approaches to decipher this complex cellular compartment. Indeed, characterization of this heterogeneous cell ecosystem has been largely accomplished with "low-resolution" approaches like morphological evaluation and immunohistochemistry, where cells are characterized using a few proteins and qualitative metrics. High-resolution, quantitative approaches, such as mass cytometry, are valuable to better understand myeloid cell diversity, functions, and to identify potential targets for novel therapies.


Assuntos
Carcinogênese , Centro Germinativo/imunologia , Imunomodulação , Linfoma de Células B/imunologia , Células Supressoras Mieloides/imunologia , Animais , Regulação Neoplásica da Expressão Gênica , Humanos , Evasão Tumoral , Microambiente Tumoral
17.
Oncotarget ; 8(25): 40079-40089, 2017 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-28445143

RESUMO

The immunoglobulin heavy chain (IGH) gene loci are subject to specific recombination events during B-cell differentiation including somatic hypermutation and class switch recombination which mark the end of immunoglobulin gene maturation in germinal centers of secondary lymph nodes. These two events rely on the activity of activation-induced cytidine deaminase (AID) which requires DNA double strand breaks be created, a potential danger to the cell. Applying 3D-fluorescence in situ hybridization coupled with immunofluorescence staining to a previously described experimental system recapitulating normal B-cell differentiation ex vivo, we have kinetically analyzed the radial positioning of the two IGH gene loci as well as their proximity with the nucleolus, heterochromatin and γH2AX foci. Our observations are consistent with the proposal that these IGH gene rearrangements take place in a specific perinucleolar "recombination compartment" where AID could be sequestered thus limiting the extent of its potentially deleterious off-target effects.


Assuntos
Linfócitos B/imunologia , Diferenciação Celular/imunologia , Nucléolo Celular/imunologia , Cadeias Pesadas de Imunoglobulinas/imunologia , Linfócitos B/metabolismo , Linhagem Celular Tumoral , Nucléolo Celular/metabolismo , Células Cultivadas , Citidina Desaminase/imunologia , Citidina Desaminase/metabolismo , Centro Germinativo/citologia , Centro Germinativo/imunologia , Centro Germinativo/metabolismo , Humanos , Switching de Imunoglobulina/genética , Switching de Imunoglobulina/imunologia , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/metabolismo , Hibridização in Situ Fluorescente/métodos , Ativação Linfocitária/imunologia , Microscopia Confocal , Hipermutação Somática de Imunoglobulina/genética , Hipermutação Somática de Imunoglobulina/imunologia
18.
Clin Rheumatol ; 36(7): 1649-1654, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28293753

RESUMO

The objective of this study is to assess the association of clinical manifestations of systemic sclerosis (SSc) with the absolute count of circulating blood monocyte subpopulations according to their membrane expression of CD16. Forty-eight consecutive patients fulfilling the 2013 ACR/EULAR classification criteria for SSc were included in this cross-sectional study. CD16+ monocyte absolute count was defined by flow cytometry and confronted to the clinical characteristics of SSc patients. Twenty-three healthy donors (HD) were randomly selected for comparison. SSc patients had an increased number of total circulating blood monocytes compared to HD (p < 0.001). The CD16- subpopulation absolute count was increased in SSc patients compared to HD (p < 0.001) but was similar in limited SSc (lSSc) and diffuse SSc (dSSc). On the contrary, the CD16+ population absolute count was increased in dSSc compared to both HD and lSSc patients (dSSc 0.071 Giga/L (±0.034) vs HD 0.039 Giga/L (±0.030), p < 0.01, and dSSc 0.071 Giga/L (±0.034) vs lSSc 0.048 Giga/L (±0.024), p < 0.05). The CD16+ monocyte subpopulation absolute count was significantly correlated with the severity of skin fibrosis evaluated by the modified Rodnan skin score (p < 0.001). The CD16+ monocyte subpopulation was also associated with pulmonary fibrosis (p < 0.05), with the severity of the restrictive ventilatory defect evaluated by total lung capacity (p < 0.05) and with the pulmonary function impairment reflected by diffusing capacity of the lungs for carbon monoxyde measures (p < 0.01). These results suggest that CD16+ monocytes are associated with the main fibrotic manifestations of SSc and their role in the pathogenesis of fibrosis in this autoimmune disorder should therefore be further considered.


Assuntos
Monócitos/metabolismo , Receptores de IgG/metabolismo , Escleroderma Sistêmico/sangue , Adulto , Estudos Transversais , Feminino , Fibrose/sangue , Fibrose/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Monócitos/patologia , Escleroderma Sistêmico/patologia , Índice de Gravidade de Doença , Pele/patologia
19.
Am J Respir Crit Care Med ; 196(3): 315-327, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28146645

RESUMO

RATIONALE: Sepsis induces a sustained immune dysfunction responsible for poor outcome and nosocomial infections. Myeloid-derived suppressor cells (MDSCs) described in cancer and inflammatory processes may be involved in sepsis-induced immune suppression, but their clinical impact remains poorly defined. OBJECTIVES: To clarify phenotype, suppressive activity, origin, and clinical impact of MDSCs in patients with sepsis. METHODS: Peripheral blood transcriptomic analysis was performed on 29 patients with sepsis and 15 healthy donors. A second cohort of 94 consecutive patients with sepsis, 11 severity-matched intensive care patients, and 67 healthy donors was prospectively enrolled for flow cytometry and functional experiments. MEASUREMENTS AND MAIN RESULTS: Genes involved in MDSC suppressive functions, including S100A12, S100A9, MMP8, and ARG1, were up-regulated in the peripheral blood of patients with sepsis. CD14posHLA-DRlow/neg monocytic (M)-MDSCs were expanded in intensive care unit patients with and without sepsis and CD14negCD15pos low-density granulocytes/granulocytic (G)-MDSCs were more specifically expanded in patients with sepsis (P < 0.001). Plasma levels of MDSC mediators S100A8/A9, S100A12, and arginase 1 were significantly increased. In vitro, CD14pos- and CD15pos-cell depletion increased T-cell proliferation in patients with sepsis. G-MDSCs, made of immature and mature granulocytes expressing high levels of degranulation markers, were specifically responsible for arginase 1 activity. High initial levels of G-MDSCs, arginase 1, and S100A12 but not M-MDSCs were associated with subsequent occurrence of nosocomial infections. CONCLUSIONS: M-MDSCs and G-MDSCs strongly contribute to T-cell dysfunction in patients with sepsis. More specifically, G-MDSCs producing arginase 1 are associated with a higher incidence of nosocomial infections and seem to be major actors of sepsis-induced immune suppression.


Assuntos
Infecção Hospitalar/imunologia , Células Supressoras Mieloides/imunologia , Sepse/imunologia , Adulto , Idoso , Proliferação de Células , Infecção Hospitalar/sangue , Feminino , Citometria de Fluxo , Granulócitos/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sepse/sangue
20.
Blood ; 129(18): 2507-2518, 2017 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-28202459

RESUMO

Follicular lymphoma (FL) is the most frequent indolent lymphoma and is characterized by the accumulation of germinal center-derived malignant B cells engaged in a bidirectional crosstalk with their supportive microenvironment in invaded lymph nodes (LNs) and bone marrow (BM). T follicular helper (TFH) cells and infiltrating stromal cells have been shown to favor FL B-cell growth, but the mechanisms of their protumoral effect and how the LN/BM microenvironment is converted into a lymphoma-permissive cell niche remain poorly understood. We demonstrated here that FL-infiltrating LN and BM stromal cells overexpressed CXCL12 in situ. Interleukin-4 high (IL-4hi) FL-TFH cells, unlike FL B cells themselves, triggered CXCL12 upregulation in human stromal cell precursors. In agreement, expression of CXCL12 was associated with IL-4 expression and signaling within the FL BM and LN niches. This IL-4/CXCL12 axis was amplified in activated lymphoid stromal cells as shown in our in vitro model of human lymphoid stroma differentiation and in an inducible mouse model of ectopic lymphoid organ formation. Finally, CXCL12 triggered primary FL B-cell activation, migration, and adhesion, a process antagonized by BTK and PI3K inhibitors. These data identified the IL-4/CXCL12 loop as a previously unrecognized pathway involved in lymphoid stroma polarization and as a potential therapeutic target in FL patients.


Assuntos
Medula Óssea/imunologia , Quimiocina CXCL12/imunologia , Interleucina-4/imunologia , Linfonodos/imunologia , Linfoma Folicular/imunologia , Transdução de Sinais/imunologia , Animais , Linfócitos B/imunologia , Linfócitos B/patologia , Medula Óssea/patologia , Movimento Celular/genética , Movimento Celular/imunologia , Quimiocina CXCL12/genética , Feminino , Humanos , Interleucina-4/genética , Linfonodos/patologia , Linfoma Folicular/genética , Linfoma Folicular/patologia , Masculino , Camundongos , Camundongos Knockout , Transdução de Sinais/genética , Células Estromais/imunologia , Células Estromais/patologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologia
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