Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 117
Filtrar
1.
Prosthet Orthot Int ; 48(3): 241, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38771773
2.
PLoS One ; 19(3): e0300892, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38512959

RESUMO

Inflammatory bowel diseases (IBD) result from uncontrolled inflammation in the intestinal mucosa leading to damage and loss of function. Both innate and adaptive immunity contribute to the inflammation of IBD and innate and adaptive immune cells reciprocally activate each other in a forward feedback loop. In order to better understand innate immune contributions to IBD, we developed a model of spontaneous 100% penetrant, early onset colitis that occurs in the absence of adaptive immunity by crossing villin-TNFAIP3 mice to RAG1-/- mice (TRAG mice). This model is driven by microbes and features increased levels of innate lymphoid cells in the intestinal mucosa. To investigate the role of type 3 innate lymphoid cells (ILC3) in the innate colitis of TRAG mice, we crossed them to retinoid orphan receptor gamma t deficient (Rorγt-/-) mice. Rorγt-/- x TRAG mice exhibited markedly reduced eosinophilia in the colonic mucosa, but colitis persisted in these mice. Colitis in Rorγt-/- x TRAG mice was characterized by increased infiltration of the intestinal mucosa by neutrophils, inflammatory monocytes, macrophages and other innate cells. RNA and cellular profiles of Rorγt-/- x TRAG mice were consistent with a lack of ILC3 and ILC3 derived cytokines, reduced antimicrobial factors, increased activation oof epithelial repair processes and reduced activation of epithelial cell STAT3. The colitis in Rorγt-/- x TRAG mice was ameliorated by antibiotic treatment indicating that microbes contribute to the ILC3-independent colitis of these mice. Together, these gene expression and cell signaling signatures reflect the double-edged sword of ILC3 in the intestine, inducing both proinflammatory and antimicrobial protective responses. Thus, Rorγt promotes eosinophilia but Rorγt and Rorγt-dependent ILC3 are dispensable for the innate colitis in TRAG mice.


Assuntos
Anti-Infecciosos , Colite , Eosinofilia , Doenças Inflamatórias Intestinais , Camundongos , Animais , Imunidade Inata , Linfócitos/metabolismo , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Inflamação/metabolismo , Mucosa Intestinal/metabolismo , Eosinofilia/metabolismo , Anti-Infecciosos/metabolismo , Retinoides , Camundongos Endogâmicos C57BL
3.
Oncogene ; 43(14): 1007-1018, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38361046

RESUMO

One-third of pediatric patients with osteosarcoma (OS) develop lung metastases (LM), which is the primary predictor of mortality. While current treatments of patients with localized bone disease have been successful in producing 5-year survival rates of 65-70%, patients with LM experience poor survival rates of only 19-30%. Unacceptably, this situation that has remained unchanged for 30 years. Thus, there is an urgent need to elucidate the mechanisms of metastatic spread in OS and to identify targetable molecular pathways that enable more effective treatments for patients with LM. We aimed to identify OS-specific gene alterations using RNA-sequencing of extremity and LM human tissues. Samples of extremity and LM tumors, including 4 matched sets, were obtained from patients with OS. Our data demonstrate aberrant regulation of the androgen receptor (AR) pathway in LM and predicts aldehyde dehydrogenase 1A1 (ALDH1A1) as a downstream target. Identification of AR pathway upregulation in human LM tissue samples may provide a target for novel therapeutics for patients with LM resistant to conventional chemotherapy.


Assuntos
Neoplasias Ósseas , Neoplasias Pulmonares , Osteossarcoma , Humanos , Criança , Aldeído Desidrogenase/metabolismo , Receptores Androgênicos/genética , Neoplasias Pulmonares/patologia , Osteossarcoma/patologia , Neoplasias Ósseas/patologia , RNA
4.
Cancer Immunol Res ; 12(3): 287-295, 2024 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-38345376

RESUMO

Immune checkpoint blockade (ICB) can induce durable cancer remission. However, only a small subset of patients gains benefits. While tumor mutation burden (TMB) differentiates responders from nonresponders in some cases, it is a weak predictor in tumor types with low mutation rates. Thus, there is an unmet need to discover a new class of genetic aberrations that predict ICB responses in these tumor types. Here, we report analyses of pan-cancer whole genomes which revealed that intragenic rearrangement (IGR) burden is significantly associated with immune infiltration in breast, ovarian, esophageal, and endometrial cancers, particularly with increased M1 macrophage and CD8+ T-cell signatures. Multivariate regression against spatially counted tumor-infiltrating lymphocytes in breast, endometrial, and ovarian cancers suggested that IGR burden is a more influential covariate than other genetic aberrations in these cancers. In the MEDI4736 trial evaluating durvalumab in esophageal adenocarcinoma, IGR burden correlated with patient benefits. In the IMVigor210 trial evaluating atezolizumab in urothelial carcinoma, IGR burden increased with platinum exposure and predicted patient benefit among TMB-low, platinum-exposed tumors. Altogether, we have demonstrated that IGR burden correlates with T-cell inflammation and predicts ICB benefit in TMB-low, IGR-dominant tumors, and in platinum-exposed tumors.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Feminino , Humanos , Inibidores de Checkpoint Imunológico , Platina , Biomarcadores Tumorais/genética , Mutação
5.
bioRxiv ; 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38106226

RESUMO

Bone is a frequent site for breast cancer metastasis. Conditioning of local tumor microenvironment through crosstalk between tumor cells and bone resident cells in the metastatic niche is a major driving force for bone colonization of cancer cells. This study demonstrates that Myocardin-related transcription factor (MRTF - a major cofactor for the transcription factor serum-response factor, SRF) activity in breast cancer cells is required for their ability to promote osteoclast differentiation of bone marrow-derived monocytes and colonize in bone. MRTF depletion in breast cancer cells affects a wide range of cell-secreted osteoclast-regulatory factors including connective tissue growth factor (CTGF), a prominent bone metastasis-associated gene that exhibit strong positive association in expression with MRTF activity in human breast cancer. Rescue experiments demonstrate that CTGF is an important paracrine mediator of pro-osteoclastogenic action of MRTF in breast cancer cells. Both SRF-dependent and -independent (SAP-domain directed) functions of MRTF are required for its ability to regulate CTGF expression and osteoclast differentiation. In conclusion, this study uncovers a novel MRTF-directed tumor-extrinsic mechanism of bone colonization of cancer cells and suggest that MRTF inhibition could be a novel strategy to suppress osteoclast activity and skeletal involvement in metastatic breast cancer.

6.
Prosthet Orthot Int ; 47(6): 565-574, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37878250

RESUMO

BACKGROUND: Understanding the psychometric strengths and limitations of outcome measures for use with people with lower limb absence (LLA) is important for selecting measures suited to evaluating patient outcomes, answering clinical and research questions, and informing health care policy. The aim of this project was to review the current psychometric evidence on outcome measures in people with LLA to determine which measures should be included in a stakeholder consensus process. METHODS: An expert panel was assembled, and a 3-stage review process was used to categorize outcome measures identified in a systematic literature review into 3 distinct categories (recommended for measures with better than adequate psychometric properties; recommended with qualification; and unable to recommend). Panelists were asked to individually categorize measures based on results of a systematic review of identified measures' psychometric properties. Each measure's final categorization was based on ≥70% agreement by all panelists. RESULTS: No outcome measure attained the ≥70% consensus threshold needed to achieve a rating of "recommend." Hence, panelists suggested combining "recommend" and "recommend with qualifications" into a single category of "recommend with qualifications." Using this approach, consensus was reached for 59 of 60 measures. Consensus could not be reached on 1 outcome measure (socket comfort score). Thirty-six outcome measures were categorized as "unable to recommend" based on available evidence; however, 23 (12 patient-reported measures and 11 performance-based measures) demonstrated adequate psychometric properties in LLA samples and were thus rated as "recommend with qualification" by the expert panel. The panel of experts were able to recommend 23 measures for inclusion in the subsequent stakeholder review. A key strength of this process was bringing together international researchers with extensive experience in developing and/or using LLA outcome measures who could assist in identifying psychometrically sound measures to include in a subsequent stakeholder consensus process. CONCLUSION: The above categorizations represent the current state of psychometric evidence on outcome measures for people with LLA and hence may change over time as additional research becomes available. The results will be used to achieve wider consensus from clinicians, health policymakers, health clinic managers, researchers, and end users (i.e., individuals with LLA) on outcome measures for the International Society of Prosthetics and Orthotics lower limb Consensus Outcome Measures for Prosthetic and Amputation ServiceS.


Assuntos
Membros Artificiais , Avaliação de Resultados em Cuidados de Saúde , Humanos , Amputação Cirúrgica , Consenso , Extremidade Inferior , Revisões Sistemáticas como Assunto
7.
PNAS Nexus ; 2(10): pgad305, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37781098

RESUMO

Actin-binding protein Profilin1 is an important regulator of actin cytoskeletal dynamics in cells and critical for embryonic development in higher eukaryotes. The objective of the present study was to examine the consequence of loss-of-function of Pfn1 in vascular endothelial cells (ECs) in vivo. We utilized a mouse model engineered for tamoxifen-inducible biallelic inactivation of the Pfn1 gene selectively in EC (Pfn1EC-KO). Widespread deletion of EC Pfn1 in adult mice leads to severe health complications presenting overt pathologies (endothelial cell death, infarct, and fibrosis) in major organ systems and evidence for inflammatory infiltrates, ultimately compromising the survival of animals within 3 weeks of gene ablation. Mice deficient in endothelial Pfn1 exhibit selective bias toward the proinflammatory myeloid-derived population of immune cells, a finding further supported by systemic elevation of proinflammatory cytokines. We further show that triggering Pfn1 depletion not only directly upregulates proinflammatory cytokine/chemokine gene expression in EC but also potentiates the paracrine effect of EC on proinflammatory gene expression in macrophages. Consistent with these findings, we provide further evidence for increased activation of Interferon Regulatory Factor 7 (IRF7) and STAT1 in EC when depleted of Pfn1. Collectively, these findings for the first time demonstrate a prominent immunological consequence of loss of endothelial Pfn1 and an indispensable role of endothelial Pfn1 in mammalian survival unlike tolerable phenotypes of Pfn1 loss in other differentiated cell types.

8.
J Biol Chem ; 299(8): 105044, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37451478

RESUMO

Overexpression of actin-binding protein profilin-1 (Pfn1) correlates with advanced disease features and adverse clinical outcome of patients with clear cell renal carcinoma, the most prevalent form of renal cancer. We previously reported that Pfn1 is predominantly overexpressed in tumor-associated vascular endothelial cells in human clear cell renal carcinoma. In this study, we combined in vivo strategies involving endothelial cell-specific depletion and overexpression of Pfn1 to demonstrate a role of vascular endothelial Pfn1 in promoting tumorigenicity and enabling progressive growth and metastasis of renal carcinoma cells in a syngeneic orthotopic mouse model of kidney cancer. We established an important role of endothelial Pfn1 in tumor angiogenesis and further identified endothelial Pfn1-dependent regulation of several pro- (VEGF, SERPINE1, CCL2) and anti-angiogenic factors (platelet factor 4) in vivo. Endothelial Pfn1 overexpression increases tumor infiltration by macrophages and concomitantly diminishes tumor infiltration by T cells including CD8+ T cells in vivo, correlating with the pattern of endothelial Pfn1-dependent changes in tumor abundance of several prominent immunomodulatory cytokines. These data were also corroborated by multiplexed quantitative immunohistochemistry and immune deconvolution analyses of RNA-seq data of clinical samples. Guided by Upstream Regulator Analysis of tumor transcriptome data, we further established endothelial Pfn1-induced Hif1α elevation and suppression of STAT1 activation. In conclusion, this study demonstrates for the first time a direct causal relationship between vascular endothelial Pfn1 dysregulation, immunosuppressive tumor microenvironment, and disease progression with mechanistic insights in kidney cancer. Our study also provides a conceptual basis for targeting Pfn1 for therapeutic benefit in kidney cancer.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Profilinas , Microambiente Tumoral , Animais , Humanos , Camundongos , Carcinoma de Células Renais/genética , Células Endoteliais/metabolismo , Neoplasias Renais/genética , Profilinas/genética , Profilinas/metabolismo , Progressão da Doença
9.
Prosthet Orthot Int ; 47(2): 123, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-37040168
10.
bioRxiv ; 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38187641

RESUMO

Dysregulated actin cytoskeleton gives rise to aberrant cell motility and metastatic spread of tumor cells. The MRTF-SRF transcriptional complex plays a key role in regulating the expressions of actin cytoskeleton-modulatory genes. In this study, we demonstrate that MRTF's interaction with SRF is critical for migration and invasion of breast cancer cells. Disruption of the MRTF-SRF interaction suppresses membrane dynamics affecting the frequency and the effectiveness of membrane protrusion during cell motility. Consistent with these phenotypic changes, we further show that MRTF promotes actin polymerization at the leading edge, a key aspect of membrane protrusion, and migration of breast cancer cells through upregulating the expression of formin-family actin nucleating/elongating protein encoding gene DIAPH3 in an SRF-dependent manner. In support of these findings, multiplexed quantitative immunohistochemistry and transcriptome analyses of clinical specimens of breast cancer further demonstrate a positive correlation between nuclear localization of MRTF with malignant traits of cancer cells as well as enrichment of MRTF/SRF gene signature in distant metastases relative to primary tumors. In conclusion, this study for the first time links the MRTF/SRF signaling axis to cell migration through the regulation of a specific actin-binding protein, and provides evidence for an association between MRTF/SRF activity and malignancy in human breast cancer.

12.
Gut Microbes ; 14(1): 2123677, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36162004

RESUMO

Changes in the spatial organization, or biogeography, of colonic microbes have been observed in human inflammatory bowel disease (IBD) and mouse models of IBD. We have developed a mouse model of IBD that occurs spontaneously and consistently in the absence of adaptive immunity. Mice expressing tumor necrosis factor-induced protein 3 (TNFAIP3) in intestinal epithelial cells (villin-TNFAIP3) develop colitis when interbred with Recombination Activating 1-deficient mice (RAG1<sup>-/-</sup>). The colitis in villin-TNFAIP3 × RAG1<sup>-/-</sup> (TRAG) mice is prevented by antibiotics, indicating a role for microbes in this innate colitis. We therefore explored the biogeography of microbes and responses to antibiotics in TRAG colitis. Laser capture microdissection and 16S rRNA sequencing revealed altered microbial populations across the transverse axis of the colon as the inner mucus layer of TRAG, but not RAG1<sup>-/-</sup>, mice was infiltrated by microbes, which included increased abundance of the classes Gammaproteobacteria and Actinobacteria. Along the longitudinal axis differences in the efficacy of antibiotics to prevent colitis were evident. Neomycin was most effective for prevention of inflammation in the cecum, while ampicillin was most effective in the proximal and distal colon. RAG1<sup>-/-</sup>, but not TRAG, mice exhibited a structured pattern of bacterial abundance with decreased Firmicutes and Proteobacteria but increased Bacteroidetes along the proximal to distal axis of the gut. TRAG mice exhibited increased relative abundance of potential pathobionts including <i>Bifidobacterium animalis</i> along the longitudinal axis of the gut whereas others, like <i>Helicobacter hepaticus</i> were increased only in the cecum. Potential beneficial organisms including <i>Roseburia</i> were decreased in the proximal regions of the TRAG colon, while <i>Bifidobacterium pseudolongulum</i> was decreased in the TRAG distal colon. Thus, the innate immune system maintains a structured, spatially organized, gut microbiome along the transverse and longitudinal axis of the gut, and disruption of this biogeography is a feature of innate immune colitis.


Assuntos
Colite , Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Ampicilina , Animais , Antibacterianos , Colo/patologia , Sulfato de Dextrana , Modelos Animais de Doenças , Humanos , Doenças Inflamatórias Intestinais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Neomicina , RNA Ribossômico 16S/genética , Proteína 3 Induzida por Fator de Necrose Tumoral alfa
13.
Medicina (Kaunas) ; 58(7)2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35888603

RESUMO

Background and Objectives: Cancer and coronary artery disease (CAD) often coexist. Compared to quantitative coronary angiography (QCA), fractional flow reserve (FFR) has emerged as a more reliable method of identifying significant coronary stenoses. We aimed to assess the specific management, safety and outcomes of FFR-guided percutaneous coronary intervention (PCI) in cancer patients with stable CAD. Materials and Methods: FFR was used to assess cancer patients that underwent coronary angiography for stable CAD between September 2008 and May 2016, and were found to have ≥50% stenosis by QCA. Patients with lesions with an FFR > 0.75 received medical therapy alone, while those with FFR ≤ 0.75 were revascularized. Procedure-related complications, all-cause mortality, nonfatal myocardial infarction, or urgent revascularizations were analyzed. Results: Fifty-seven patients with stable CAD underwent FFR on 57 lesions. Out of 31 patients with ≥70% stenosis as measured by QCA, 14 (45.1%) had an FFR ≥ 0.75 and lesions were reclassified as moderate and did not receive PCI nor DAPT. Out of 26 patients with <70% stenosis as measured by QCA, 6 (23%) had an FFR < 0.75 and were reclassified as severe and were treated with PCI and associated DAPT. No periprocedural complications, urgent revascularization, acute coronary syndromes, or cardiovascular deaths were noted. There was a 22.8% mortality at 1 year, all cancer related. Patients who received a stent by FFR assessment showed a significant association with decreased risk of all-cause death (HR: 0.37, 95% CI 0.15−0.90, p = 0.03). Conclusions: Further studies are needed to define the optimal therapeutic approach for cancer patients with CAD. Using an FFR cut-off point of 0.75 to guide PCI translates into fewer interventions and can facilitate cancer care. There was an overall reduction in mortality in patients that received a stent, suggesting increased resilience to cancer therapy and progression.


Assuntos
Doença da Artéria Coronariana , Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Neoplasias , Intervenção Coronária Percutânea , Constrição Patológica , Angiografia Coronária/métodos , Doença da Artéria Coronariana/complicações , Estenose Coronária/complicações , Estenose Coronária/cirurgia , Seguimentos , Humanos , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Intervenção Coronária Percutânea/métodos , Inibidores da Agregação Plaquetária/uso terapêutico , Resultado do Tratamento
14.
Front Immunol ; 13: 877533, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35572549

RESUMO

Infectious diseases are one of the leading causes of morbidity and mortality worldwide, affecting high-risk populations such as children and the elderly. Pathogens usually activate local immune responses at the site of infection, resulting in both protective and inflammatory responses, which may lead to local changes in the microbiota, metabolites, and the cytokine environment. Although some pathogens can disseminate and cause systemic disease, increasing evidence suggests that local infections can affect tissues not directly invaded. In particular, diseases occurring at distal mucosal barriers such as the lung and the intestine seem to be linked, as shown by epidemiological studies in humans. These mucosal barriers have bidirectional interactions based mainly on multiple signals derived from the microbiota, which has been termed as the gut-lung axis. However, the effects observed in such distal places are still incompletely understood. Most of the current research focuses on the systemic impact of changes in microbiota and bacterial metabolites during infection, which could further modulate immune responses at distal tissue sites. Here, we describe how the gut microbiota and associated metabolites play key roles in maintaining local homeostasis and preventing enteric infection by direct and indirect mechanisms. Subsequently, we discuss recent murine and human studies linking infectious diseases with changes occurring at distal mucosal barriers, with particular emphasis on bacterial and viral infections affecting the lung and the gastrointestinal tract. Further, we discuss the potential mechanisms by which pathogens may cause such effects, promoting either protection or susceptibility to secondary infection.


Assuntos
Doenças Transmissíveis , Microbioma Gastrointestinal , Microbiota , Pneumonia , Idoso , Animais , Bactérias/metabolismo , Criança , Humanos , Camundongos
15.
Prosthet Orthot Int ; 46(1): 1, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35179520
16.
J STEM Outreach ; 5(2)2022.
Artigo em Inglês | MEDLINE | ID: mdl-36910569

RESUMO

The University of Pittsburgh Medical Center Hillman Cancer Center Academy (Hillman Academy) has the primary goal of reaching high school students from underrepresented and disadvantaged backgrounds and guiding them through a cutting-edge research and professional development experience that positions them for success in STEM. With this focus, the Hillman Academy has provided nearly 300 authentic mentored research internship opportunities to 239 students from diverse backgrounds over the past 13 years most of whom matriculated into STEM majors in higher education. These efforts have helped shape a more diverse generation of future scientists and clinicians, who will enrich these fields with their unique perspectives and lived experiences. In this paper, we describe our program and the strategies that led to its growth into a National Institutes of Health Youth Enjoy Science-funded program including our unique multi-site structure, tiered mentoring platform, multifaceted recruitment approach, professional and academic development activities, and a special highlight of a set of projects with Deaf and Hard of Hearing students. We also share student survey data from the past six years that indicate satisfaction with the program, self-perceived gains in key areas of scientific development, awareness of careers in STEM, and an increased desire to pursue advanced degrees in STEM.

17.
Prosthet Orthot Int ; 45(6): 445, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34789710

Assuntos
Leitura , Humanos
18.
J Glob Health ; 11: 04058, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34671462

RESUMO

BACKGROUND: In their work to end the tuberculosis (TB) epidemic in lower- and middle-income countries, national TB programs need a tool to measure, monitor, and strengthen relevant capabilities to create a continuous transformation of data into action (D2A) to improve TB program results. However, there is a lack of scientific evidence to determine specific measurement dimensions of a D2A continuum that enables TB programs to identify the barriers and enablers of D2A and to guide the selection of interventions appropriate for the context and decision-making capabilities of various TB program actors. METHODS: A systematic review of peer-reviewed and grey literature was conducted per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A total of 48 peer-reviewed publications were selected for data extraction and analysis. RESULTS: The findings show that selected publications discussed the health system level, stakeholders involved in decision making, decision type, data system, data sources, data use enablers and barriers, decision-making framework and steps, decision outcome/impact, and how that outcome was measured. The findings highlight barriers and enablers to data use and explain the relationship among data sources, decision type, and stakeholders. Seventeen D2A measurement dimensions were identified. CONCLUSIONS: Transforming data to action is a continuous process that recognizes that data use indicators vary by type of decisions, decision makers, and the health system level at which decisions are made. As a logical next step, the project team plans to develop and validate a D2A continuum toolkit that will include a measurement scale, implementation guide, and data collection and analysis Microsoft Excel workbook.


Assuntos
Tuberculose , Humanos , Tuberculose/epidemiologia , Tuberculose/prevenção & controle
19.
J Immunol ; 207(5): 1265-1274, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34348976

RESUMO

IL-9-producing Th cells, termed Th9 cells, contribute to immunity against parasites and cancers but have detrimental roles in allergic disease and colitis. Th9 cells differentiate in response to IL-4 and TGF-ß, but these signals are insufficient to drive Th9 differentiation in the absence of IL-2. IL-2-induced STAT5 activation is required for chromatin accessibility within Il9 enhancer and promoter regions and directly transactivates the Il9 locus. STAT5 also suppresses gene expression during Th9 cell development, but these roles are less well defined. In this study, we demonstrate that human allergy-associated Th9 cells exhibited a signature of STAT5-mediated gene repression that is associated with the silencing of a Th17-like transcriptional signature. In murine Th9 cell differentiation, blockade of IL-2/STAT5 signaling induced the expression of IL-17 and the Th17-associated transcription factor Rorγt. However, IL-2-deprived Th9 cells did not exhibit a significant Th17- or STAT3-associated transcriptional signature. Consistent with these observations, differentiation of IL-17-producing cells under these conditions was STAT3-independent but did require Rorγt and BATF. Furthermore, ectopic expression of Rorγt and BATF partially rescued IL-17 production in STAT3-deficient Th17 cells, highlighting the importance of these factors in this process. Although STAT3 was not required for the differentiation of IL-17-producing cells under IL-2-deprived Th9 conditions, their prolonged survival was STAT3-dependent, potentially explaining why STAT3-independent IL-17 production is not commonly observed in vivo. Together, our data suggest that IL-2/STAT5 signaling plays an important role in controlling the balance of a Th9 versus a Th17-like differentiation program in vitro and in allergic disease.


Assuntos
Fator de Transcrição STAT5 , Células Th17 , Animais , Diferenciação Celular , Regulação da Expressão Gênica , Humanos , Interleucina-9/genética , Interleucina-9/metabolismo , Camundongos , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT5/metabolismo , Células Th17/metabolismo
20.
Prosthet Orthot Int ; 45(4): 295, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34269755
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...