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1.
Int Immunopharmacol ; 129: 111625, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38354509

RESUMO

The immunomodulatory (IM) subtype of triple negative breast cancer (TNBC) exhibits high expression of immune cell signaling genes and is more responsive to immunotherapy. However, the specific mechanism underlying this phenomenon remains unclear. One of the potential key genes appears to be the cytotoxic and regulatory T cell molecule (CRTAM). A cohort of 360 previously untreated TNBC patients from Fudan University Shanghai Cancer Center (FUSCC) underwent RNA sequencing analysis of their primary tumor tissue. Combined with three RNA-seq datasets obtained from the GEO database, a LASSO regression analysis was conducted to identify genes specific to the IM type of TNBC. Our findings revealed elevated CRTAM expression in the IM-type TNBC, which correlated with a favorable overall survival and recurrence-free survival in TNBC patients. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated a strong association between CRTAM and immune responses as well as immune system processes. Notably, CRTAM overexpression induced STAT1 phosphorylation and upregulation of interferon-stimulated genes. We also found that CRTAM enhanced tumor-associated immune cell infiltration, especially CD8+ T cells, which may be related to the increased expression of MHC class I molecules caused by CRTAM overexpression. These results suggest that CRTAM may serve as a potential biomarker for predicting the efficacy of immunotherapy in TNBC.


Assuntos
Linfócitos T CD8-Positivos , Imunoglobulinas , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/terapia , Neoplasias de Mama Triplo Negativas/metabolismo , China , Ativação Linfocitária/fisiologia
2.
Methods Cell Biol ; 178: 173-193, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37516525

RESUMO

Cell-to-cell communication is necessary to orchestrate effective immune responses against disease-causing agents and in homeostasis. During immune synapsis, transfer of small extracellular vesicles that contain bioactive molecules, including microRNAs, occurs from the T lymphocyte to the antigen-presenting cell. In this chapter, we describe the methodology to identify and validate specific microRNAs shuttled from T lymphocytes to B cells upon immune synapse formation, and to analyze their functional impact on post-synaptic antigen-presenting cells.


Assuntos
Vesículas Extracelulares , MicroRNAs , MicroRNAs/genética , Sinapses Imunológicas/fisiologia , Linfócitos T , Células Apresentadoras de Antígenos , Comunicação Celular/genética , Vesículas Extracelulares/genética , Ativação Linfocitária/fisiologia
3.
Int J Mol Sci ; 23(4)2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35216346

RESUMO

Absent in melanoma 2 (AIM2) is a cytosolic dsDNA sensor that has been broadly studied for its role in inflammasome assembly. However, little is known about the function of AIM2 in adaptive immune cells. The purpose of this study was to investigate whether AIM2 has a cell-intrinsic role in CD4+ T cell differentiation or function. We found that AIM2 is expressed in both human and mouse CD4+ T cells and that its expression is affected by T cell receptor (TCR) activation. Naïve CD4+ T cells from AIM2-deficient (Aim2-/-) mice showed higher ability to maintain forkhead box P3 (FOXP3) expression in vitro, while their capacity to differentiate into T helper (Th)1, Th2 or Th17 cells remained unaltered. Transcriptional profiling by RNA sequencing showed that AIM2 might affect regulatory T cell (Treg) stability not by controlling the expression of Treg signature genes, but through the regulation of the cell's metabolism. In addition, in a T cell transfer model of colitis, Aim2-/--naïve T cells induced less severe body weight loss and displayed a higher ability to differentiate into FOXP3+ cells in vivo. In conclusion, we show that AIM2 function is not confined to innate immune cells but is also important in CD4+ T cells. Our data identify AIM2 as a regulator of FOXP3+ Treg cell differentiation and as a potential intervention target for restoring T cell homeostasis.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Linfócitos T Reguladores/metabolismo , Adulto , Animais , Diferenciação Celular/fisiologia , Colite/metabolismo , Feminino , Fatores de Transcrição Forkhead/metabolismo , Humanos , Inflamassomos/metabolismo , Ativação Linfocitária/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células Th17/metabolismo
4.
Commun Biol ; 5(1): 40, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-35017678

RESUMO

T cells are critically important for host defense against infections. T cell activation is specific because signal initiation requires T cell receptor (TCR) recognition of foreign antigen peptides presented by major histocompatibility complexes (pMHC) on antigen presenting cells (APCs). Recent advances reveal that the TCR acts as a mechanoreceptor, but it remains unclear how pMHC/TCR engagement generates mechanical forces that are converted to intracellular signals. Here we propose a TCR Bending Mechanosignal (TBM) model, in which local bending of the T cell membrane on the nanometer scale allows sustained contact of relatively small pMHC/TCR complexes interspersed among large surface receptors and adhesion molecules on the opposing surfaces of T cells and APCs. Localized T cell membrane bending is suggested to increase accessibility of TCR signaling domains to phosphorylation, facilitate selective recognition of agonists that form catch bonds, and reduce noise signals associated with slip bonds.


Assuntos
Fenômenos Biomecânicos/fisiologia , Membrana Celular , Mecanorreceptores , Receptores de Antígenos de Linfócitos T , Transdução de Sinais/fisiologia , Células Apresentadoras de Antígenos/química , Membrana Celular/química , Membrana Celular/metabolismo , Células Cultivadas , Antígenos de Histocompatibilidade/química , Antígenos de Histocompatibilidade/metabolismo , Humanos , Ativação Linfocitária/fisiologia , Mecanorreceptores/química , Mecanorreceptores/metabolismo , Receptores de Antígenos de Linfócitos T/química , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/química , Linfócitos T/citologia , Linfócitos T/metabolismo
5.
Cell Rep ; 38(2): 110223, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-35021072

RESUMO

MEK1 and MEK2, the only known activators of ERK, are attractive therapeutic candidates for both cancer and autoimmune diseases. However, how MEK signaling finely regulates immune cell activation is only partially understood. To address this question, we specifically delete Mek1 in hematopoietic cells in the Mek2 null background. Characterization of an allelic series of Mek mutants reveals the presence of distinct degrees of spontaneous B cell activation, which are inversely proportional to the levels of MEK proteins and ERK activation. While Mek1 and Mek2 null mutants have a normal lifespan, 1Mek1 and 1Mek2 mutants retaining only one functional Mek1 or Mek2 allele in hematopoietic cell lineages die from glomerulonephritis and lymphoproliferative disorders, respectively. This establishes that the fine-tuning of the ERK/MAPK pathway is critical to regulate B and T cell activation and function and that each MEK isoform plays distinct roles during lymphocyte activation and disease development.


Assuntos
Ativação Linfocitária/fisiologia , MAP Quinase Quinase 1/metabolismo , MAP Quinase Quinase 2/metabolismo , Alelos , Animais , Linfócitos B/metabolismo , Feminino , Humanos , Ativação Linfocitária/genética , MAP Quinase Quinase 1/fisiologia , MAP Quinase Quinase 2/genética , MAP Quinase Quinase 2/fisiologia , Sistema de Sinalização das MAP Quinases/genética , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Camundongos , Camundongos da Linhagem 129 , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Fosforilação , Transdução de Sinais/fisiologia , Linfócitos T/metabolismo
6.
Mol Biol Rep ; 49(2): 1593-1599, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34783987

RESUMO

BACKGROUND: Inflammation is a complex mechanism with an objective to destroy and eliminate the invading microorganisms. During acute inflammation, the neutrophils are the major cells involved in this process and, although they defend the organism, must die to not generate damage. The two major mechanisms that drive neutrophils to death are: apoptosis and a novel mechanism recently discovered denominated NETosis. This process is a "suicidal mechanism", in which the cells release "neutrophil extracellular traps" (NETs) during the inflammatory response. Octyl gallate (OG) is one of the gallic acid derivates, with several protective effects, such as antioxidant and anti-inflammatory in cancer models. Thus, this study aimed to investigate the action of OG on the proliferation of lymphocytes, neutrophils activation, and its effectiveness in an experimental sepsis model. METHODS: Lymphocytes and neutrophils were obtained from healthy donors. Cell viability, apoptosis, NETs release and antioxidant capacity of OG were observed. In addition, survival was evaluated in an experimental model of sepsis in C57BL/6 mice. RESULTS: Our study demonstrated, for the first time, that the OG can act as an inhibitor of reactive oxygen species (ROS) release, NETs formation in primary human neutrophils and, modulates the lipopolysaccharide (LPS) effect in neutrophil apoptosis. The OG also inhibited peripheral blood mononuclear cells (PBMCs) proliferation in vitro. Despite the positive results, we did not observe an increase in the survival of septic animals. CONCLUSIONS: The pharmacological potential of OG, modulating activation of neutrophils and lymphocytes, suggests the use as an adjuvant therapeutic strategy in inflammatory diseases.


Assuntos
Armadilhas Extracelulares/metabolismo , Ácido Gálico/análogos & derivados , Ativação Linfocitária/fisiologia , Animais , Apoptose/efeitos dos fármacos , Armadilhas Extracelulares/efeitos dos fármacos , Ácido Gálico/metabolismo , Ácido Gálico/farmacologia , Voluntários Saudáveis , Humanos , Inflamação , Leucócitos Mononucleares/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/efeitos dos fármacos , Espécies Reativas de Oxigênio/farmacologia , Sepse
7.
Cell Host Microbe ; 30(1): 17-30.e9, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34822777

RESUMO

Bacterial activation of T helper 17 (Th17) cells exacerbates mouse models of autoimmunity, but how human-associated bacteria impact Th17-driven disease remains elusive. We show that human gut Actinobacterium Eggerthella lenta induces intestinal Th17 activation by lifting inhibition of the Th17 transcription factor Rorγt through cell- and antigen-independent mechanisms. E. lenta is enriched in inflammatory bowel disease (IBD) patients and worsens colitis in a Rorc-dependent manner in mice. Th17 activation varies across E. lenta strains, which is attributable to the cardiac glycoside reductase 2 (Cgr2) enzyme. Cgr2 is sufficient to induce interleukin (IL)-17a, a major Th17 cytokine. cgr2+ E. lenta deplete putative steroidal glycosides in pure culture; related compounds are negatively associated with human IBD severity. Finally, leveraging the sensitivity of Cgr2 to dietary arginine, we prevented E. lenta-induced intestinal inflammation in mice. Together, these results support a role for human gut bacterial metabolism in driving Th17-dependent autoimmunity.


Assuntos
Colite/metabolismo , Microbioma Gastrointestinal/fisiologia , Ativação Linfocitária/fisiologia , Células Th17/metabolismo , Actinobacteria , Animais , Bactérias/metabolismo , Colite/imunologia , Citocinas , Suplementos Nutricionais , Modelos Animais de Doenças , Feminino , Humanos , Doenças Inflamatórias Intestinais/microbiologia , Interleucina-17/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo
8.
Physiol Rep ; 9(23): e15147, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34889067

RESUMO

Regular exercise is associated with changes in peripheral blood mononuclear cell (PBMC) proportions that have enhanced effector functions in young and old adults; however, the effects of acute exercise on PBMC nutrient sensors and metabolic function in active young adults is unknown. To fill this gap, activation status and nutrient-sensing mechanisms of PBMCs isolated from 21 healthy active adults (20-35 yr; 36.5 ± 6.3 V̇O2peak ) were characterized before and after 30 min of moderate-to-vigorous cycling (65%-75% V̇O2peak ). In addition, changes in PBMC mitochondrial respiratory function in response to exercise were assessed using high-resolution respirometry. There was an increase in the number of activated CD69+/CD4 (79% increase) and CD69+/CD8 (166% increase) T-cells in response to the acute bout of exercise, while the nutrient-sensing mechanisms remained unchanged. PBMC mitochondrial respiration did not increase on a cell-per-cell basis, however, mitochondrial oxidative capacity (OXPHOS) increased at the tissue level (18.6 pmol/(s*ml blood) versus 29.3 pmol/(s*ml blood); p < 0.05) in response to acute exercise. Thus, this study shows that acute exercise preferentially mobilizes activated T-cells while concomitantly increasing PBMC mitochondrial oxidative capacity at the tissue level, rather than acutely changing mitochondrial oxidative capacity at the cellular level in young adults.


Assuntos
Respiração Celular/fisiologia , Metabolismo Energético/fisiologia , Exercício Físico/fisiologia , Leucócitos Mononucleares/metabolismo , Mitocôndrias/metabolismo , Adulto , Feminino , Humanos , Ativação Linfocitária/fisiologia , Masculino , Fosforilação Oxidativa , Estresse Oxidativo/fisiologia , Consumo de Oxigênio/fisiologia , Adulto Jovem
9.
Front Immunol ; 12: 714613, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34880854

RESUMO

Recent findings have shown that iron is a powerful regulator of immune responses, which is of broad importance because iron deficiency is highly prevalent worldwide. However, the underlying reasons of why iron is needed by lymphocytes remain unclear. Using a combination of mathematical modelling, bioinformatic analysis and experimental work, we studied how iron influences T-cells. We identified iron-interacting proteins in CD4+ and CD8+ T-cell proteomes that were differentially expressed during activation, suggesting that pathways enriched with such proteins, including histone demethylation, may be impaired by iron deficiency. Consistent with this, iron-starved Th17 cells showed elevated expression of the repressive histone mark H3K27me3 and displayed reduced RORγt and IL-17a, highlighting a previously unappreciated role for iron in T-cell differentiation. Quantitatively, we estimated T-cell iron content and calculated that T-cell iron demand rapidly and substantially increases after activation. We modelled that these increased requirements will not be met during clinically defined iron deficiency, indicating that normalizing serum iron may benefit adaptive immunity. Conversely, modelling predicted that excess serum iron would not enhance CD8+ T-cell responses, which we confirmed by immunising inducible hepcidin knock-out mice that have very high serum iron concentrations. Therefore, iron deficiency impairs multiple aspects of T-cell responses, while iron overload likely has milder effects.


Assuntos
Proteínas de Ligação ao Ferro/metabolismo , Ferro/metabolismo , Ativação Linfocitária/fisiologia , Subpopulações de Linfócitos T/imunologia , Animais , Células Cultivadas , Conjuntos de Dados como Assunto , Epigênese Genética , Ontologia Genética , Heme/metabolismo , Hepcidinas/deficiência , Hepcidinas/imunologia , Humanos , Deficiências de Ferro/imunologia , Sobrecarga de Ferro/imunologia , Linfopoese , Camundongos , Camundongos Knockout , Modelos Biológicos , Proteoma , Subpopulações de Linfócitos T/metabolismo , Células Th17/efeitos dos fármacos , Células Th17/metabolismo
10.
Bull Cancer ; 108(10S): S128-S140, 2021 Oct.
Artigo em Francês | MEDLINE | ID: mdl-34920795

RESUMO

CAR-T cells represent a new approach to anti-tumor cellular immunotherapy allowing to combine the recognition of tumor antigens on target cells and the activation, proliferation and cytotoxic capacity of T lymphocytes. Impressive clinical results have been obtained with CAR-T cells targeting the CD19 antigen in relapsing or refractory B cell malignant lymphomas or acute lymphoblastic leukemias, with complete response rates of 40 to 90%. However, 30 to 50% of responding patients in B malignancies will escape treatment secondarily, and the effectiveness of these approaches in solid tumors remains limited. Different mechanisms of primary resistance and/or escape to CAR-T cells have been described. This review aims to describe these mechanisms and explore potential ways for optimization. We will see that the initial response and its long-term persistence depends on several parameters: the functional characteristics of the CAR-T cells in vivo, the expression of targeted antigens on tumor cells, the development of a immunosuppressive microenvironment. Or of an immune response directed against the CAR molecule. In solid tumors in particular, the specificity of the antigen target and the "homing" of CAR-T cells in the tumor site are additional elements to consider. A better knowledge of mechanisms of resistance will help to improve the clinical outcomes by either modulating the construction and the production of CAR-T cells and/or to combine them with other immunotherapeutic approaches to better control the tumor microenvironment.


Assuntos
Imunoterapia Adotiva/métodos , Neoplasias/terapia , Receptores de Antígenos Quiméricos/imunologia , Linfócitos T/transplante , Evasão Tumoral/imunologia , Microambiente Tumoral/imunologia , Antígenos de Neoplasias/imunologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/fisiologia , Humanos , Tolerância Imunológica , Imunidade Celular , Interleucinas/farmacologia , Ativação Linfocitária/fisiologia , Neoplasias/imunologia , Fenótipo , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
11.
J Diabetes Res ; 2021: 6581213, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34778464

RESUMO

Although type 1 diabetes is thought to be an organ-specific autoimmune disease, mediated by effective CD4+ and CD8+ T cells, it has recently become clear that B cells participate in the initiation and progress of this disease. Indeed, B cell deletion can prevent or reverse autoimmune diabetes in nonobese diabetic mice and even result in partially remaining ß cell function in patients with new-onset type 1 diabetes. This review summarizes the dual role of B cells in this process not only of pathogenic effect but also of immunoregulatory function in type 1 diabetes. We focus on the impact that B cells have on regulating the activation, proliferation, and cytokine production of self-reactive T cells along with regulatory T cells, with the aim of providing a better understanding of the interactions between T and B cells in immunopathogenesis and improving the efficacy of interventions for clinical practice.


Assuntos
Linfócitos B/fisiologia , Diabetes Mellitus Tipo 1/terapia , Linfócitos T/metabolismo , Animais , Linfócitos B/citologia , Diabetes Mellitus Tipo 1/fisiopatologia , Ativação Linfocitária/fisiologia , Camundongos , Camundongos Endogâmicos NOD/metabolismo , Linfócitos T/citologia
12.
Asian Pac J Cancer Prev ; 22(11): 3447-3453, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34837898

RESUMO

OBJECTIVE: This study aimed to identify the distribution of M2 macrophage and Treg in Nasopharyngeal Carcinoma (NPC) tumor tissue samples. The presence of these two groups of cells was further correlated to clinical stage, tumor size, the lymphatic node involvement, and metastasis. METHODS: The total of 50 formalin-fixed paraffin-embedded (FFPE) NPC tissue samples was collected retrospectively (27 samples) and prospectively (23 samples). Samples were FFPE tissue slices. Immunohistochemistry was done on the FFPE tissue slides using anti-CD-163 and anti-FoxP-3 antibodies for M2 macrophage and Treg detection, respectively. The M2 macrophage interpretation was performed by eye-balling method and the score was divided into 0 (negative), 1 (scant), 2 (focal), and 3 (abundant). The average number of Treg FOXP3+ cells in 5 high power fields (HPF) was calculated. The relationship of M2 macrophage and Treg was tested with Spearman's correlation. The relationship between M2 macrophage and Treg with clinical stage, tumor size, node involvement and metastasis was tested by chi square, with p<0.1. RESULTS: M2 macrophage and Treg were positive correlated (r=0.469, p<0.001). The presence of M2 macrophage and regulatory T cell (Treg) was significantly correlated to tumor size (p= 0.091 for M2 macrophage and p=0.022 for Treg) and clinical stage (p= 0.030 for M2 macrophage and p= 0.002 for Treg), but did not correlate with lymphatic node involvement and metastasis. CONCLUSIONS: In Epstein-Barr virus related NPC tumor microenvironment, the presence of M2 macrophage was correlated with Treg, and both types of the cells were correlated with tumor size and clinical stages.


Assuntos
Macrófagos , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/patologia , Linfócitos T Reguladores , Microambiente Tumoral , Adolescente , Adulto , Estudos Transversais , Infecções por Vírus Epstein-Barr/virologia , Feminino , Herpesvirus Humano 4/genética , Humanos , Imuno-Histoquímica , Ativação Linfocitária/fisiologia , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/virologia , Neoplasias Nasofaríngeas/virologia , Estadiamento de Neoplasias , Estudos Prospectivos , RNA Viral/fisiologia , Estudos Retrospectivos , Receptor 3 Toll-Like , Carga Tumoral , Adulto Jovem
13.
Int J Mol Sci ; 22(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34445118

RESUMO

The existence of CD4+ cytotoxic T cells (CTLs) at relatively high levels under different pathological conditions in vivo suggests their role in protective and/or pathogenic immune functions. CD4+ CTLs utilize the fundamental cytotoxic effector mechanisms also utilized by CD8+ CTLs and natural killer cells. During long-term cultivation, CD4+ T cells were also shown to acquire cytotoxic functions. In this study, CD4+ human T-cell clones derived from activated peripheral blood lymphocytes of healthy young adults were examined for the expression of cytotoxic machinery components. Cystatin F is a protein inhibitor of cysteine cathepsins, synthesized by CD8+ CTLs and natural killer cells. Cystatin F affects the cytotoxic efficacy of these cells by inhibiting the major progranzyme convertases cathepsins C and H as well as cathepsin L, which is involved in perforin activation. Here, we show that human CD4+ T-cell clones express the cysteine cathepsins that are involved in the activation of granzymes and perforin. CD4+ T-cell clones contained both the inactive, dimeric form as well as the active, monomeric form of cystatin F. As in CD8+ CTLs, cysteine cathepsins C and H were the major targets of cystatin F in CD4+ T-cell clones. Furthermore, CD4+ T-cell clones expressed the active forms of perforin and granzymes A and B. The levels of the cystatin F decreased with time in culture concomitantly with an increase in the activities of granzymes A and B. Therefore, our results suggest that cystatin F plays a role in regulating CD4+ T cell cytotoxicity. Since cystatin F can be secreted and taken up by bystander cells, our results suggest that CD4+ CTLs may also be involved in regulating immune responses through cystatin F secretion.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Cisteína/metabolismo , Inibidores de Proteases/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Catepsina C/metabolismo , Catepsina L/metabolismo , Linhagem Celular Tumoral , Células Clonais , Granzimas/metabolismo , Humanos , Células Jurkat , Células Matadoras Naturais/metabolismo , Ativação Linfocitária/fisiologia , Linfócitos T Citotóxicos/metabolismo
14.
Mol Immunol ; 137: 187-200, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34274794

RESUMO

Aging is associated with excessive bone loss that is not counteracted with the development of new bone. However, the mechanisms underlying age-related bone loss are not completely clear. Myeloid-derived suppressor cells (MDSCs) are a population of heterogenous immature myeloid cells with immunosuppressive functions that are known to stimulate tumor-induced bone lysis. In this study, we investigated the association of MDSCs and age-related bone loss in mice. Our results shown that aging increased the accumulation of MDSCs in the bone marrow and spleen, while in the meantime potentiated the osteoclastogenic activity of the CD11b+Ly6ChiLy6G+ monocytic subpopulation of MDSCs. In addition, CD11b+Ly6ChiLy6G+ MDSCs from old mice exhibited increased expression of c-fms compared to young mice, and were more sensitive to RANKL-induced osteoclast gene expression. On the other hand, old mice showed elevated production of IL-6 and receptor activator of nuclear factor kappa-B ligand (RANKL) in the circulation. Furthermore, IL-6 and RANKL were able to induce the proliferation of CD11b+Ly6ChiLy6G+ MDSCs and up-regulate c-fms expression. Moreover, CD11b+Ly6ChiLy6G+ MDSCs obtained from old mice showed increased antigen-specific T cell suppressive function, pStat3 expression, and cytokine production in response to inflammatory stimulation, compared to those cells obtained from young mice. Our findings suggest that CD11b+Ly6ChiLy6G+ MDSCs are a source of osteoclast precursors that together with the presence of persistent, low-grade inflammation, contribute to age-associated bone loss in mice.


Assuntos
Envelhecimento/fisiologia , Células Mieloides/fisiologia , Células Supressoras Mieloides/fisiologia , Osteoclastos/fisiologia , Osteogênese/fisiologia , Envelhecimento/metabolismo , Animais , Antígenos Ly/metabolismo , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Modelos Animais de Doenças , Expressão Gênica/fisiologia , Inflamação/metabolismo , Inflamação/patologia , Ativação Linfocitária/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Monócitos/metabolismo , Monócitos/fisiologia , Células Mieloides/metabolismo , Células Supressoras Mieloides/metabolismo , Osteoclastos/metabolismo , Baço/metabolismo , Baço/fisiologia
15.
Int J Mol Sci ; 22(14)2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34299363

RESUMO

The ubiquitin-proteasome system regulates biological processes in normal and diseased states. Recent investigations have focused on ubiquitin-dependent modifications and their impacts on cellular function, commitment, and differentiation. Ubiquitination is reversed by deubiquitinases, including ubiquitin-specific peptidases (USPs), whose roles have been widely investigated. In this review, we explore recent findings highlighting the regulatory functions of USPs in osteoblasts and providing insight into the molecular mechanisms governing their actions during bone formation. We also give a brief overview of our work on USP53, a target of PTH in osteoblasts and a regulator of mesenchymal cell lineage fate decisions. Emerging evidence addresses questions pertaining to the complex layers of regulation exerted by USPs on osteoblast signaling. We provide a short overview of our and others' understanding of how USPs modulate osteoblastogenesis. However, further studies using knockout mouse models are needed to fully understand the mechanisms underpinning USPs actions.


Assuntos
Osteoblastos/metabolismo , Proteases Específicas de Ubiquitina/metabolismo , Animais , Linhagem da Célula/fisiologia , Humanos , Ativação Linfocitária/fisiologia , Células-Tronco Mesenquimais/metabolismo , Osteogênese/fisiologia , Transdução de Sinais/fisiologia , Ubiquitinação/fisiologia
16.
PLoS One ; 16(7): e0254184, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34234374

RESUMO

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy with few available targeted therapies. We previously reported that the phosphatase calcineurin (Cn) is required for LIC (leukemia Initiating Capacity) potential of T-ALL pointing to Cn as an interesting therapeutic target. Calcineurin inhibitors have however unwanted side effect. NFAT transcription factors play crucial roles downstream of calcineurin during thymocyte development, T cell differentiation, activation and anergy. Here we elucidate NFAT functional relevance in T-ALL. Using murine T-ALL models in which Nfat genes can be inactivated either singly or in combination, we show that NFATs are required for T-ALL LIC potential and essential to survival, proliferation and migration of T-ALL cells. We also demonstrate that Nfat genes are functionally redundant in T-ALL and identified a node of genes commonly deregulated upon Cn or NFAT inactivation, which may serve as future candidate targets for T-ALL.


Assuntos
Fatores de Transcrição NFATC/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Linfócitos T/metabolismo , Animais , Calcineurina/metabolismo , Inibidores de Calcineurina/farmacologia , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Linfócitos T/efeitos dos fármacos
17.
Ann Clin Transl Neurol ; 8(9): 1786-1795, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34289265

RESUMO

OBJECTIVE: JNK pathway-associated phosphatase (JKAP) is previously reported to regulate immune/inflammatory process via T-cell signaling, and closely involves in neurological diseases, while its implication in Parkinson's disease (PD) is unknown. Therefore, this study aimed to investigate the correlation of JKAP with Th1/Th2/Th17 cells and their clinical roles in PD patients, and then further explore the effect of JKAP on regulating CD4+ T-cell differentiation in PD. METHODS: Totally 50 PD patients and 50 age-/gender-matched controls were enrolled. Their blood samples were collected and proposed to ELISA and flow cytometry assays for JKAP, Th1, Th2, and Th17 measurements. In vitro, CD4+ T cells were isolated from PD patients then transfected with JKAP overexpression and knockdown Lentivirus, followed by detection of markers (CD25+ cell proportion, CD69+ cell proportion, IFN-γ, IL10, and IL17). RESULTS: JKAP was downregulated in PD patients compared to controls, which also showed good potency to discriminate them. Besides, JKAP negatively correlated with Th1 and Th17 cell proportions, but did not associate with Th2 cell proportion in PD patients; Interestingly, JKAP did not correlated with Th1, Th2, or Th17 cell proportions in controls. Furthermore, JKAP correlated with some parts of unified Parkinson's Disease Rating Scale (UPDRS) and Mini-Mental State Examination (MMSE) score. In vitro, JKAP overexpression repressed CD4+ T-cell activation and its differentiation into Th1 and Th17 cells in PD, while JKAP knockdown appeared opposite effect. INTERPRETATION: JKAP associates with disease risk and severity, correlates with Th1 and Th17 cells, and regulates CD4+ T-cell activation/differentiation in PD.


Assuntos
Fosfatases de Especificidade Dupla/sangue , Fosfatases da Proteína Quinase Ativada por Mitógeno/sangue , Doença de Parkinson/sangue , Doença de Parkinson/fisiopatologia , Células Th1 , Células Th17 , Idoso , Linfócitos T CD4-Positivos , Diferenciação Celular/fisiologia , Regulação para Baixo , Feminino , Humanos , Ativação Linfocitária/fisiologia , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/epidemiologia , Gravidade do Paciente , Risco
18.
Biochim Biophys Acta Mol Basis Dis ; 1867(10): 166184, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34087422

RESUMO

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with unclear pathogenesis. We previously reported that syngenetic, activated lymphocyte-derived DNA (ALD-DNA) could robustly elicit macrophage activation, which plays an important role in the pathogenesis of murine lupus nephritis. In addition, extracellular HMGB1 obviously facilitated the accumulation of ALD-DNA in endosomes and promoted macrophage inflammation. While the detailed mechanism was still unknown. In this study, we found that HMGB1 could obviously change the DNA uptake pathways in macrophages. ALD-DNA alone was mainly uptake by the low efficient and unselective macropinocytosis, while extracellular HMGB1 potently promoted the more efficient and specific clathrin-/caveolin-1-dependent receptor-mediated endocytosis pathways, and led to the rapid and abundant aggregation of ALD-DNA in endosomes. This effect relied on the DNA binding ability and TLR2/TLR4 of HMGB1. Our study not only helped us to understand the promotion mechanisms of extracellular HMGB1 on ALD-DNA-induced macrophage inflammation, but also provided some clues to the pathogenesis of SLE.


Assuntos
DNA/metabolismo , Endocitose/fisiologia , Endossomos/metabolismo , Proteína HMGB1/metabolismo , Inflamação/imunologia , Macrófagos/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Linhagem Celular , Feminino , Nefrite Lúpica/metabolismo , Ativação Linfocitária/fisiologia , Linfócitos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Células RAW 264.7
19.
Int J Mol Sci ; 22(10)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065512

RESUMO

Multisubunit cullin-RING ubiquitin ligase 4 (CRL4)-DCAF12 recognizes the C-terminal degron containing acidic amino acid residues. However, its physiological roles and substrates are largely unknown. Purification of CRL4-DCAF12 complexes revealed a wide range of potential substrates, including MOV10, an "ancient" RNA-induced silencing complex (RISC) complex RNA helicase. We show that DCAF12 controls the MOV10 protein level via its C-terminal motif in a proteasome- and CRL-dependent manner. Next, we generated Dcaf12 knockout mice and demonstrated that the DCAF12-mediated degradation of MOV10 is conserved in mice and humans. Detailed analysis of Dcaf12-deficient mice revealed that their testes produce fewer mature sperms, phenotype accompanied by elevated MOV10 and imbalance in meiotic markers SCP3 and γ-H2AX. Additionally, the percentages of splenic CD4+ T and natural killer T (NKT) cell populations were significantly altered. In vitro, activated Dcaf12-deficient T cells displayed inappropriately stabilized MOV10 and increased levels of activated caspases. In summary, we identified MOV10 as a novel substrate of CRL4-DCAF12 and demonstrated the biological relevance of the DCAF12-MOV10 pathway in spermatogenesis and T cell activation.


Assuntos
Antígenos de Neoplasias/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Células T Matadoras Naturais/metabolismo , RNA Helicases/metabolismo , Espermatogênese/fisiologia , Ubiquitina-Proteína Ligases/metabolismo , Animais , Linhagem Celular , Linhagem Celular Tumoral , Células HCT116 , Células HEK293 , Células HeLa , Humanos , Ativação Linfocitária/fisiologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Complexo de Endopeptidases do Proteassoma/metabolismo , Ubiquitina/metabolismo
20.
Immunology ; 164(2): 358-371, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34043816

RESUMO

Increasing evidence indicates that peripheral immune cells play a prominent role in neurodegeneration connected to protein misfolding, which are associated with formation of aberrant aggregates, including soluble protein misfolded oligomers. The precise links, however, between the physicochemical features of diverse oligomers and their effects on the immune system, particularly on adaptive immunity, remain currently unexplored, due partly to the transient and heterogeneous nature of the oligomers themselves. To overcome these limitations, we took advantage of two stable and well-characterized types of model oligomers (A and B), formed by HypF-N bacterial protein, type B oligomers displaying lower solvent-exposed hydrophobicity. Exposure to oligomers of human peripheral blood mononuclear cells (PBMCs) revealed differential effects, with type B, but not type A, oligomers leading to a reduction in CD4+ cells. Type A oligomers promoted enhanced differentiation towards CD4+ CD25High FoxP3+ Tregs and displayed a higher suppressive effect on lymphocyte proliferation than Tregs treated with oligomers B or untreated cells. Moreover, our results reveal Th1 and Th17 lymphocyte differentiation mediated by type A oligomers and a differential balance of TGF-ß, IL-6, IL-23, IFN-γ and IL-10 mediators. These results indicate that type B oligomers recapitulate some of the biological responses associated with Parkinson's disease in peripheral immunocompetent cells, while type A oligomers resemble responses associated with Alzheimer's disease. We anticipate that further studies characterizing the differential effects of protein misfolded oligomers on the peripheral immune system may lead to the development of blood-based diagnostics, which could report on the type and properties of oligomers present in patients.


Assuntos
Leucócitos Mononucleares/metabolismo , Deficiências na Proteostase/metabolismo , Adulto , Linfócitos T CD4-Positivos/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Citocinas/metabolismo , Humanos , Ativação Linfocitária/fisiologia , Pessoa de Meia-Idade , Dobramento de Proteína , Linfócitos T Reguladores/metabolismo , Células Th1/metabolismo , Células Th17/metabolismo
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