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1.
Int J Mol Sci ; 21(13)2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32630064

RESUMO

Vimentin is an intermediate filament protein that plays key roles in integration of cytoskeletal functions, and therefore in basic cellular processes such as cell division and migration. Consequently, vimentin has complex implications in pathophysiology. Vimentin is required for a proper immune response, but it can also act as an autoantigen in autoimmune diseases or as a damage signal. Although vimentin is a predominantly cytoplasmic protein, it can also appear at extracellular locations, either in a secreted form or at the surface of numerous cell types, often in relation to cell activation, inflammation, injury or senescence. Cell surface targeting of vimentin appears to associate with the occurrence of certain posttranslational modifications, such as phosphorylation and/or oxidative damage. At the cell surface, vimentin can act as a receptor for bacterial and viral pathogens. Indeed, vimentin has been shown to play important roles in virus attachment and entry of severe acute respiratory syndrome-related coronavirus (SARS-CoV), dengue and encephalitis viruses, among others. Moreover, the presence of vimentin in specific virus-targeted cells and its induction by proinflammatory cytokines and tissue damage contribute to its implication in viral infection. Here, we recapitulate some of the pathophysiological implications of vimentin, including the involvement of cell surface vimentin in interaction with pathogens, with a special focus on its role as a cellular receptor or co-receptor for viruses. In addition, we provide a perspective on approaches to target vimentin, including antibodies or chemical agents that could modulate these interactions to potentially interfere with viral pathogenesis, which could be useful when multi-target antiviral strategies are needed.


Assuntos
Vírus da SARS/fisiologia , Vimentina/metabolismo , Viroses/patologia , Anticorpos/imunologia , Anticorpos/metabolismo , Anticorpos/uso terapêutico , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/tratamento farmacológico , Interações Hospedeiro-Patógeno , Humanos , Pandemias , Pneumonia Viral/tratamento farmacológico , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/uso terapêutico , Vimentina/química , Vimentina/imunologia , Viroses/tratamento farmacológico , Viroses/metabolismo , Replicação Viral/efeitos dos fármacos
2.
Am J Kidney Dis ; 75(1): 138-143, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31515140

RESUMO

Improving precision in predicting alloreactivity is an important unmet need and may require individualized consideration of non-HLA antibodies. We report a 21-year-old man with kidney failure from immunoglobulin A nephropathy who met all traditional criteria for a "low-risk" transplant for immune memory. He was unsensitized and received a haplotype-matched living donor kidney transplant from his mother. There were no anti-HLA donor-specific antibodies and flow cross-match was negative. After immediate function, he developed delayed graft function on postoperative day 2. The transplant biopsy specimen was suggestive of antibody-mediated rejection and acute tubular injury with increased vimentin proximal tubular expression compared to the implantation biopsy specimen. He had a history of juvenile idiopathic arthritis, and non-HLA antibody screening demonstrated preformed anti-vimentin antibody. He was successfully treated with plasmapheresis, intravenous immunoglobulin, antithymocyte globulin, and methylprednisolone, with renal recovery. The follow-up biopsy specimen demonstrated decreased vimentin expression with decreased alloinflammation, and graft function remains stable at 1 year posttransplantation (estimated glomerular filtration rate, 62mL/min/1.73m2). We postulate that preformed anti-vimentin autoantibodies bound to vimentin expressed on apoptotic tubular epithelial cells induced by ischemia-reperfusion injury and to constitutively expressed vimentin on peritubular capillaries and podocytes. Our case is suggestive of the involvement of anti-vimentin antibody, for which the pathogenic epitopes may be exposed during ischemia-reperfusion injury.


Assuntos
Anticorpos/imunologia , Glomerulonefrite por IGA/cirurgia , Rejeição de Enxerto/imunologia , Falência Renal Crônica/cirurgia , Transplante de Rim , Vimentina/imunologia , Soro Antilinfocitário/uso terapêutico , Função Retardada do Enxerto/imunologia , Função Retardada do Enxerto/terapia , Glomerulonefrite por IGA/complicações , Glucocorticoides/uso terapêutico , Rejeição de Enxerto/terapia , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Fatores Imunológicos/uso terapêutico , Falência Renal Crônica/etiologia , Masculino , Metilprednisolona/uso terapêutico , Plasmaferese , Adulto Jovem
3.
Eur J Histochem ; 63(4)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31833329

RESUMO

In fluorescence microscopy, light radiation can be used to bleach fluorescent molecules in formalin-fixed and paraffin-embedded (FFPE) samples, in order to increase the ratio between signal of interest and background autofluorescence. We tested if the same principle can be exploited in bright field microscopy to bleach pigmented melanoma FFPE sections together with cell morphology maintenance. After dewaxing and rehydration, serial FFPE sections of a feline diffuse iris melanoma, a canine dermal melanoma, a gray horse dermal melanoma and a swine cutaneous melanoma were irradiated with visible light for 1, 2, 3, 4 and 5 days, prior to Hematoxylin and Eosin staining. Complete bleaching was obtained after 1-day treatment in feline and swine melanomas, while 2 and 3 days were required in canine and equine neoplasms, respectively. In all treated samples, cell morphology was maintained. Photo-induced bleaching combined with immunohistochemistry was tested after a 3-day photo-treatment using five different markers. According to the literature, in all samples neoplastic cells stained positive for vimentin, S100 and PNL2, while negative for FVIII and pancytokeratin. In conclusion, visible light can be effectively exploited to bleach pigmented melanoma FFPE sections prior to perform routine histochemical and immunohistochemical stains.


Assuntos
Melaninas/efeitos da radiação , Melanoma/patologia , Fotodegradação , Animais , Anticorpos Monoclonais Murinos/imunologia , Gatos , Cães , Formaldeído/química , Cabras , Cavalos , Imuno-Histoquímica , Luz , Melanoma/veterinária , Camundongos , Inclusão em Parafina , Projetos Piloto , Coelhos , Proteínas S100/imunologia , Suínos , Temperatura , Vimentina/imunologia
4.
Turk J Med Sci ; 49(5): 1498-1502, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31651120

RESUMO

Background/aim: Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovial inflammation. The study aimed to assess serum 14-3-3eta, anti-CarP, and anti-Sa in seronegative RA (SNRA) patients who were treatment-naïve as well as in healthy subjects. This is the first study in the literature to examine these autoantibodies together in SNRA patients. Materials and methods: Forty-five treatment-naïve SNRA patients and 45 healthy subjects were recruited. Drugs change the levels of autoantibodies; therefore, patients who took any medication had been excluded from our study. Anti-carbamylated protein, anti-Sa, and 14-3-3eta were measured by using three different ELISA kits. Results: Median serum concentration of healthy controls in 14-3-3eta was 0.02 (0.02­0.27) ng/mL. Median serum concentration of SNRA patients in 14-3-3eta was 1.00 (0.48­1.28) ng/mL. Data were analyzed with Mann­Whitney U tests; the P-value was <0.001 in 14-3-3eta. Receiver operating characteristic (ROC) curve analysis showed that 14-3-3eta in SNR compared to healthy controls had a significant (P < 0.001) area under the curve (AUC) of 0.90 (95% confidence interval, 0.83­0.96). At a cutoff of ≥0.33 ng/mL, the ROC curve yielded a sensitivity of 88.9%, a specificity of 82.2%, a positive predictive value of 83.3%, and a negative predictive value of 88.1%. Conclusion: We found that 14-3-3eta can be used as a diagnostic marker in SNRA.


Assuntos
Proteínas 14-3-3/sangue , Anticorpos Anti-Proteína Citrulinada/sangue , Artrite Reumatoide/sangue , Autoanticorpos/sangue , Carbamatos/imunologia , Vimentina/imunologia , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Sorológicos
5.
Analyst ; 144(19): 5785-5793, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31463505

RESUMO

Profiling of extracellular vesicles (EVs) is an emerging area in the field of liquid biopsies because of their innate significance in diseases and abundant information reflecting disease status. However, unbiased enrichment of EVs and thorough profiling of EVs is challenging. In this paper, we present a simple strategy to immobilize and analyze EVs for multiple markers on a single microfluidic device and perform differentiated immunostaining-based characterization of extracellular vesicles (DICE). This device, composed of four quadrants with a single inlet, captures biotinylated EVs efficiently and facilitates multiplexed immunostaining to profile their extracellular proteins, allowing for a multiplexed approach for non-invasive cancer diagnostics in the future. From controlled sample experiments using cancer cell line derived EVs and specific fluorescence staining with lipophilic dyes, we identified that the DICE device is capable of isolating biotinylated EVs with 84.4% immobilization efficiency. We extended our study to profile EVs of 9 clinical samples from non-small cell lung cancer (NSCLC) patients and healthy donors and found that the DICE device successfully facilitates immunofluorescent staining for both the NSCLC patients and the healthy control. This versatile and simple method to profile EVs could be extended to EVs of any biological origin, promoting discoveries of the role of EVs in disease diagnostics and monitoring.


Assuntos
Biomarcadores Tumorais/sangue , Vesículas Extracelulares/química , Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas/métodos , Anticorpos/imunologia , Antígeno B7-H1/sangue , Antígeno B7-H1/imunologia , Biomarcadores Tumorais/imunologia , Biotina/química , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Receptores ErbB/sangue , Receptores ErbB/imunologia , Imuno-Histoquímica/métodos , Neoplasias Pulmonares/diagnóstico , Técnicas Analíticas Microfluídicas/instrumentação , Estudo de Prova de Conceito , Tetraspanina 29/sangue , Tetraspanina 29/imunologia , Vimentina/sangue , Vimentina/imunologia
6.
Reumatismo ; 71(1): 1-12, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30932437

RESUMO

Rheumatoid factor and antibodies against cyclic citrullinated peptides represent a diagnostic hallmark in rheumatoid arthritis (RA). However, over the last decades many other autoantibodies have been identified. Several proteins can trigger an aberrant autoimmune response in their native form while others acquire this feature after post-translational modifications such as citrullination, carbamylation or acetylation. It is of interest that also the enzymes catalyzing such post-translational modifications (e.g. the protein arginine deiminases) can transform themselves into autoantibodies in RA. The purpose of this review article is to provide an overview of relevant literature published over the last years regarding novel autoantibodies and their possible diagnostic and prognostic significance in RA.


Assuntos
Autoanticorpos/metabolismo , Citrulinação , Peptídeos Cíclicos/imunologia , Vimentina/imunologia , Anticorpos Antinucleares/imunologia , Anticorpos Antinucleares/metabolismo , Especificidade de Anticorpos , Artrite Reumatoide/imunologia , Autoanticorpos/imunologia , Antígenos Nucleares do Vírus Epstein-Barr/imunologia , Antígenos Nucleares do Vírus Epstein-Barr/metabolismo , Humanos , Hidrolases/imunologia , Hidrolases/metabolismo , Queratinas/imunologia , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/metabolismo , Carbamilação de Proteínas , Fator Reumatoide , Vimentina/metabolismo , Proteínas Virais/imunologia , Proteínas Virais/metabolismo
7.
Hum Immunol ; 80(8): 602-607, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30926354

RESUMO

Non-HLA antibodies are recognized as a potential source of antibody mediated rejection following transplantation. The epitopes which lead to production of these antibodies are a result of tissue disruption, specifically endothelium, secondary to inflammation and injury. Vimentin is a cytoskeletal protein involved in many aspects of cellular organization, signaling, and proliferation. Recently, antivimentin antibodies have been shown to be important not only for rheumatological autoimmune diseases, but also cardiac and renal transplant dysfunction. In cardiac transplant recipients, antivimentin antibodies are associated with coronary artery vasculopathy and chronic graft loss. In renal transplantation, antivimentin antibodies are detected prior to transplantation and are also correlated with chronic graft dysfunction. In renal transplant recipients, antivimentin antibodies seen prior to transplantation are thought to be secondary to chronic endothelial injury during hemodialysis and therefore more prevalent prior to renal transplant than cardiac transplantation. In this review, we will examine the generation and pathogenesis of antivimentin antibodies. Given that these antibodies appear to be associated with both post-cardiac and -renal transplant dysfunction, developing standard detection paradigms may be important for risk stratification prior to transplantation. Finally, understanding the pathogenesis of antivimentin antibodies may lead to the development potential therapies in order to improve long-term survival.


Assuntos
Autoanticorpos/metabolismo , Citoesqueleto/metabolismo , Rejeição de Enxerto/imunologia , Transplante de Coração , Transplante de Rim , Vimentina/metabolismo , Animais , Sobrevivência de Enxerto , Humanos , Risco , Vimentina/imunologia
8.
J Surg Res ; 240: 115-123, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30927618

RESUMO

BACKGROUND: Tumor immune reactions not only provide host defense but also accelerate tumor immune escape and phenotype switching. Here, we examined the association of programmed cell death ligand 1 (PD-L1) expression with epithelial-mesenchymal transition (EMT)-associated markers in pancreatic ductal adenocarcinoma (PDA) within the context of the tumor microenvironment. MATERIALS AND METHODS: PDA samples from 36 patients were analyzed for PD-L1, vimentin, E-cadherin, and Snail expressions and for PDA cell and immune cell infiltration. PD-L1 expression and EMT in PDA cell lines under conditions of altering interferon gamma (IFN-γ) signals were also assessed. RESULTS: Immunohistochemistry revealed a significant correlation between vimentin and PD-L1 expression, whereas double staining showed them to be simultaneously expressed by PDA cells. Positive vimentin expression was associated with the infiltration of a lower number of CD8+ T cells and a higher number of FoxP3+ cells and poor patient prognosis (P = 0.03). PDA tumor cells promoted PD-L1 expression and EMT under the presence of IFN-γ, which was inhibited by the signal transducer and activator of transcription (STAT)1 small interfering RNA. CONCLUSIONS: Strong correlations were observed between PD-L1 expression, EMT, and the immunosuppressive tumor microenvironment. Targeting STAT1 combined with PD-1/PD-L1 immunotherapy may improve outcomes for patients with PDA.


Assuntos
Antígeno B7-H1/metabolismo , Carcinoma Ductal Pancreático/imunologia , Transição Epitelial-Mesenquimal/imunologia , Interferon gama/metabolismo , Neoplasias Pancreáticas/imunologia , Idoso , Antineoplásicos Imunológicos/farmacologia , Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/terapia , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Humanos , Interferon gama/imunologia , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Pâncreas/imunologia , Pâncreas/patologia , Pâncreas/cirurgia , Pancreatectomia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/terapia , RNA Interferente Pequeno/metabolismo , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Vimentina/imunologia , Vimentina/metabolismo
9.
Methods Mol Biol ; 1904: 401-415, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30539482

RESUMO

Pritumumab, a natural human IgG1kappa mAb, was isolated from the regional lymph node of a patient with cervical cancer. This antibody has been reported to bind the cytoskeletal protein vimentin, and to cell surface expressed vimentin referred to as ecto-domain vimentin (EDV). Here, we report details of the development of a potency of binding assay for pritumumab as a prerequisite before pursuing clinical trials. The enzyme linked immunosorbent assay (ELISA) to detect antibody-binding antigen can serve as a potency assay for release of manufactured samples to be used in clinical studies. Several layers of controls for this assay along with suitability testing for reagents and components of the assay must be developed before the assay can be incorporated for stability testing and release of manufatured samples.


Assuntos
Anticorpos Monoclonais/imunologia , Vimentina/imunologia , Animais , Anticorpos Monoclonais/metabolismo , Afinidade de Anticorpos , Ensaio de Imunoadsorção Enzimática , Humanos , Cinética , Ligação Proteica/imunologia , Coelhos , Vimentina/metabolismo
10.
Am J Pathol ; 189(1): 190-199, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30315765

RESUMO

Oral squamous cell carcinoma (OSCC) is the most common malignant cancer, with high mortality rates in advanced stages. Recent studies have shown that the expression of ALPK1 mRNA and its inhibitory differentiation function are associated with cancer progression. However, the expression and clinicopathologic features of ALPK1 in OSCC remain unexplored. Herein, the authors investigated the expression patterns of ALPK1 in 39 matched OSCC patients and examined the relationship between ALPK1 protein expression and clinicopathologic factors using immunohistochemical scores. Using Western blot analysis, ALPK1 expression was found to be significantly higher in tumor tissues than that in nontumor tissues. Through an immunoreactive scoring system, a significantly higher number of advanced-stage tumor size T4 and lymph node metastasis N2 exhibited higher ALPK1 expression levels than that exhibited by T1/T2/T3 tumors and N0/N1. In addition, ALPK1 protein expression was aberrant in malignant oral cancer cell lines compared with that in pre-malignant oral epithelial cells, whereas minimal expression was observed in normal oral epithelial cells. Knockdown of ALPK1 resulted in a significant reduction in cell growth, migration, and invasion capacity in vitro. Consequently, expression of N-cadherin and vimentin decreased in ALPK1-deficient cells. Thus, these results suggest that ALPK1 serves as a potential biomarker and target for OSCC development in late stages.


Assuntos
Biomarcadores Tumorais/biossíntese , Carcinoma de Células Escamosas/enzimologia , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/biossíntese , Proteínas Quinases/biossíntese , Neoplasias da Língua/enzimologia , Adulto , Antígenos CD/genética , Antígenos CD/imunologia , Antígenos CD/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/imunologia , Caderinas/genética , Caderinas/imunologia , Caderinas/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Feminino , Técnicas de Silenciamento de Genes , Humanos , Queratinócitos/imunologia , Queratinócitos/metabolismo , Queratinócitos/patologia , Metástase Linfática/genética , Metástase Linfática/imunologia , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/imunologia , Estadiamento de Neoplasias , Proteínas Quinases/genética , Proteínas Quinases/imunologia , Neoplasias da Língua/genética , Neoplasias da Língua/imunologia , Neoplasias da Língua/patologia , Vimentina/genética , Vimentina/imunologia , Vimentina/metabolismo
11.
Mol Immunol ; 104: 37-46, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30399492

RESUMO

Vimentin is an intermediate filament protein traditionally considered to be an intracellular protein with a structural role. However, recent evidence suggests that vimentin can also be found outside the cell in disease conditions such as cancer, traumatic tissue injury, and inflammation. Extracellular vimentin was previously found to stimulate innate immunity by increasing monocyte and macrophage ability to kill bacteria. However, vimentin has also been previously found to decrease neutrophil infiltration into inflamed tissue. How extracellular vimentin affects the initiation of adaptive immune responses is unknown. Initiation of adaptive immunity involves priming of naïve T cells by antigen-presenting cells, the most effective of which are dendritic cells (DCs). In this study, we demonstrate how extracellular vimentin modulates lipopolysaccharide (LPS) - induced activation of human DCs. Using cytometric bead arrays, we show that extracellular vimentin decreases LPS-activated DC secretion of pro-inflammatory cytokines IL-6 and IL-12 while increasing secretion of the anti-inflammatory cytokine IL-10. Using flow cytometry, we show that extracellular vimentin does not significantly affect LPS-induced DC surface expression of MHC I (HLA-ABC) or MHC II (HLA-DR) presentation molecules, costimulatory factors (CD80, CD86), or the DC maturation marker (CD83). Further, LPS-stimulated DCs co-cultured with allogeneic naïve CD4 + T cells (Th0) induced less secretion of the pro-inflammatory Th1 effector cytokine IFN-γ in the presence of vimentin than in the presence of LPS alone. This result suggests that vimentin reduces Th1 differentiation. Taken together, our data suggest that extracellular vimentin may inhibit pro-inflammatory adaptive immune responses, by blocking DC secretion of pro-inflammatory cytokines. Thus, extracellular vimentin may play an important role in cancer or trauma-complications by inducing suppression of the adaptive immune response. In a positive sense, the presence of extracellular vimentin may prevent tissue-damage from contributing to the development of autoimmunity. Consequently, extracellular vimentin may become a novel drug target for treatment of a variety of pro- and anti-inflammatory disease conditions.


Assuntos
Citocinas/imunologia , Células Dendríticas/imunologia , Vimentina/imunologia , Antígenos CD/imunologia , Células Cultivadas , Células Dendríticas/citologia , Antígenos HLA/imunologia , Humanos , Lipopolissacarídeos/farmacologia , Células Th1/citologia , Células Th1/imunologia
12.
Microsc Res Tech ; 81(11): 1268-1274, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30351479

RESUMO

Telocyte (TC) is an interesting unique interstitial cell demonstrated in many human and animal tissues and organs. This study verified, for the first time, the pattern of TC distribution in the testicular tissue of New Zealand White rabbits using histological, immunohistochemical, and electron microscopic tools. Rabbit testicular tissue samples were obtained from three pairs of adult healthy New Zealand white rabbit by surgical procedures. The testicular tissues were stained with hematoxyline-eosin, Crossmon's trichrome and Periodic acid Schiff. The immunohistochemistry was performed using three different antibodies CD34, CD117, and vimentin. The testes were examined by scanning and transmission electron microscopy. Histologically, TCs formed a sheath surrounding the seminiferous tubules. Other TCs were located in the interstitial tissue of the rabbit testis. Immunohistochemically, TCs reacted strongly with CD34, CD117, and vimentin. Scanning electron microscopic findings clearly elucidated the spreading pattern of TCs and their cytoplasmic processes with the interstitial tissue including blood vessels. Both homocellular and heterocellular junctions were demonstrated by transmission electron microscope. On the basis of TCs distribution and connections, the before mentioned data suggested that, TCs may play a potential role in maintaining the testicular construction and regulation. A future work is needed to clarify the actual role played by TCs in monitoring testicular fertility. RESEARCH HIGHLIGHTS: Telocyte (TC) is a unique cell demonstrated in human and animal tissues. TCs formed a sheath surrounding the seminiferous tubules in rabbits and may be located in interstitial tissue. Immunohistochemically, TCs reacted strongly with CD34 and CD117.


Assuntos
Células do Tecido Conjuntivo/ultraestrutura , Tecido Conjuntivo/anatomia & histologia , Telócitos/ultraestrutura , Testículo/anatomia & histologia , Testículo/citologia , Animais , Anticorpos/imunologia , Antígenos CD34/imunologia , Células do Tecido Conjuntivo/fisiologia , Imunofluorescência , Imuno-Histoquímica , Masculino , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Proteínas Proto-Oncogênicas c-kit/imunologia , Coelhos , Telócitos/fisiologia , Vimentina/imunologia
13.
J Clin Invest ; 128(10): 4604-4621, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30106752

RESUMO

Regulatory T cells (Tregs) are critical for maintaining immune homeostasis. However, current Treg immunotherapies do not optimally treat inflammatory diseases in patients. Understanding the cellular processes that control Treg function may allow for the augmentation of therapeutic efficacy. In contrast to activated conventional T cells, in which protein kinase C-θ (PKC-θ) localizes to the contact point between T cells and antigen-presenting cells, in human and mouse Tregs, PKC-θ localizes to the opposite end of the cell in the distal pole complex (DPC). Here, using a phosphoproteomic screen, we identified the intermediate filament vimentin as a PKC-θ phospho target and show that vimentin forms a DPC superstructure on which PKC-θ accumulates. Treatment of mouse Tregs with either a clinically relevant PKC-θ inhibitor or vimentin siRNA disrupted vimentin and enhanced Treg metabolic and suppressive activity. Moreover, vimentin-disrupted mouse Tregs were significantly better than controls at suppressing alloreactive T cell priming in graft-versus-host disease (GVHD) and GVHD lethality, using a complete MHC-mismatch mouse model of acute GVHD (C57BL/6 donor into BALB/c host). Interestingly, vimentin disruption augmented the suppressor function of PKC-θ-deficient mouse Tregs. This suggests that enhanced Treg activity after PKC-θ inhibition is secondary to effects on vimentin, not just PKC-θ kinase activity inhibition. Our data demonstrate that vimentin is a key metabolic and functional controller of Treg activity and provide proof of principle that disruption of vimentin is a feasible, translationally relevant method to enhance Treg potency.


Assuntos
Células Apresentadoras de Antígenos/imunologia , Doença Enxerto-Hospedeiro/imunologia , Filamentos Intermediários/imunologia , Ativação Linfocitária , Linfócitos T Reguladores/imunologia , Vimentina/imunologia , Animais , Células Apresentadoras de Antígenos/patologia , Modelos Animais de Doenças , Doença Enxerto-Hospedeiro/genética , Doença Enxerto-Hospedeiro/patologia , Humanos , Filamentos Intermediários/genética , Filamentos Intermediários/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Proteína Quinase C-theta/genética , Proteína Quinase C-theta/imunologia , Linfócitos T Reguladores/patologia , Vimentina/genética
14.
Indian J Pathol Microbiol ; 61(3): 407-409, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30004067

RESUMO

Sclerosing pneumocytoma (SP) is an uncommon benign tumor, and metastasis of SP has been rarely reported. Here, we report the case of a 26-year-old woman with surgically confirmed SP. The tumor diameter was 40 mm, and metastasis to mediastinal and regional lymph nodes was observed. Immunohistochemically, both surface and round cells were positive for epithelial membrane antigen, thyroid transcription factor 1, and vimentin. Only surface cells expressed creatine kinase, carcinoembryonic antigen, napsin A, and cytokeratin 7, and only round cells expressed progesterone receptor. Ki-67 was detected in ~3% of cells, and the rate of weak positive p53 staining was 3%. Both cell types were negative for chromogranin A, synaptophysin, CD3, and CK20. Multiple metastases in a young SP patient are very rare, and potential mechanisms of metastasis may be related to epithelial-mesenchymal transformation.


Assuntos
Linfonodos/fisiologia , Hemangioma Esclerosante Pulmonar/complicações , Hemangioma Esclerosante Pulmonar/patologia , Adulto , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Biópsia , Feminino , Humanos , Imuno-Histoquímica , Linfonodos/citologia , Metástase Linfática , Mucina-1/genética , Mucina-1/imunologia , Hemangioma Esclerosante Pulmonar/diagnóstico , Hemangioma Esclerosante Pulmonar/cirurgia , Fator Nuclear 1 de Tireoide/genética , Fator Nuclear 1 de Tireoide/imunologia , Vimentina/genética , Vimentina/imunologia
15.
Autoimmun Rev ; 17(9): 926-934, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30009963

RESUMO

Vimentin is a protein of intermediate filament family, which is expressed in all mesenchymal cells. Vimentin plays a key role in the physiology of the cell, cellular interactions and the functioning of the immune system. Post-translationally modified and native forms of vimentin are involved in the pathogenesis of inflammation and many autoimmune diseases: rheumatoid arthritis, sarcoidosis, systemic lupus erythematosus, antiphospholipid syndrome, Crohn's disease, ankylosing spondyloarthritis and idiopathic pulmonary fibrosis. Modifications of the protein lead to the formation of antigenic epitopes and, as a result, to the synthesis of antibodies. Citrullinated, carbamylated and acetylated forms of vimentin participate in the pathogenesis of RA, and antibodies against them serve as diagnostic and prognostic markers of the disease. Epitopes of native vimentin are antigenic in the group of HLA-DRB1*0301 positive patients with sarcoidosis. In addition, vimentin takes part in pathogenesis of tubulointerstitial inflammation and glomerulonephritis in lupus. In antiphospholipid syndrome interactions of vimentin and cardiolipin on the surface of apoptotic cells lead to the formation of an immunogenic complex. Antibodies against vimentin/cardiolipin complex are involved in the mechanism of thrombogenesis and serve to identify patients seronegative for antibodies to cardiolipin and ß2glycoprotein-I with the clinical features. Post-translationally modified form of the protein is citrullinated and MMP-degraded vimentin, which was found in serum of patients with Crohn's disease and ankylosing spondyloarthritis.


Assuntos
Artrite Reumatoide/imunologia , Autoimunidade/efeitos dos fármacos , Lúpus Eritematoso Sistêmico/imunologia , Processamento de Proteína Pós-Traducional/genética , Vimentina/imunologia , Humanos
17.
Arq Bras Cardiol ; 110(4): 348-353, 2018 Apr.
Artigo em Inglês, Português | MEDLINE | ID: mdl-29538505

RESUMO

BACKGROUND: Vimentin is a main structural protein of the cell, a component of intermediate cell filaments and immersed in cytoplasm. Vimentin is mimicked by some bacterial proteins and anti-vimentin antibodies occur in autoimmune cardiac disease, as rheumatic fever. In this work we studied vimentin distribution on LLC-MK2 cells infected with T. cruzi and anti-vimentin antibodies in sera from several clinical pictures of Chagas' disease or American Trypanosomiasis, in order to elucidate any vimentin involvement in the humoral response of this pathology. OBJECTIVE: We standardized an indirect immunofluorescence assay (IFI) to determine sub cellular expression in either parasites and host cells, and ELISA to evaluate anti-vimentin antibodies in sera fron chagasic patients. METHODS: We analyzed the distribution of vimentin in culture cells using indirect fluorescent assays, using as external controls anti-T. cruzi sera, derived from chronic infected patients for identification of the parasites in the same model. After infection and growth of T.cruzi amastigotes, those cells express larger amounts of vimentin, with heavy staining of cytoplasm outside the parasitophorous vacuole and some particle shadowing patterns, suggesting that vimentin are associated with cell cytoplasm. Anti-vimentin antibodies were present in most American trypanosomiasis samples, but notably, they are much more present in acute (76, 9%) or clinical defined syndromes, especially cardiac disease (87, 9%). Paradoxically, they were relatively infrequent in asymptomatic (25%) infected patients, which had a clearly positive serological reaction to parasite antigens, but had low frequency of anti-vimentin antibodies, similar to controls (2,5%). CONCLUSION: Our current data revealed that anti-vimentin antibodies induced during T. cruzi infection could be a marker of active disease in the host and its levels could also justify drug therapy in American Trypanosomiasis chronic infection, as a large group of asymptomatic patients would be submitted to treatment with frequent adverse reactions of the available drugs. Anti-vimentin antibodies could be a marker of cardiac muscle cell damage, appearing in American Trypanosomiasis patients during active muscle cell damage.


Assuntos
Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Doença de Chagas/imunologia , Trypanosoma cruzi/imunologia , Vimentina/imunologia , Análise de Variância , Animais , Anticorpos Antiprotozoários/análise , Antígenos de Protozoários/análise , Células Cultivadas , Ensaio de Imunoadsorção Enzimática/métodos , Técnica Indireta de Fluorescência para Anticorpo/métodos , Humanos , Macaca mulatta , Valores de Referência , Estatísticas não Paramétricas
18.
Arthritis Res Ther ; 20(1): 30, 2018 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-29433534

RESUMO

BACKGROUND: Sjögren's syndrome (SS) is a primary autoimmune disease (pSS) or secondarily associated with other autoimmune diseases (sSS). The mechanisms underlying immune dysregulation in this syndrome remain unknown, and clinically it is difficult to diagnose owing to a lack of specific biomarkers. METHODS: We extracted immunoglobulins (Igs) from the sera of patients with sSS associated with rheumatoid arthritis (RA) and used them to screen a phage display library of peptides with random sequences. RESULTS: Our results show that an sSS-specific peptide, designated 3S-P, was recognized by sera of 68.2% (60 of 88) patients with sSS, 66.2% of patients with RA-sSS, and 76.5% of patients with systemic lupus erythematosus (SLE)-sSS. The anti-3S-P antibody was scarcely found in patients with pSS (1.8%), RA (1.3%), SLE (4.2%), ankylosing spondylitis (0%), and gout (3.3%), as well as in healthy donors (2%). The 3S-P-binding Igs (antibodies) were used to identify antigens from salivary glands and synovial tissues from patients with sSS. A putative target autoantigen expressed in the synovium and salivary gland recognized by anti-3S-P antibody was identified as self-vimentin. CONCLUSIONS: This novel autoantibody is highly specific in the diagnosis of sSS, and the underlying molecular mechanism of the disease might be epitope spreading involved with vimentin.


Assuntos
Artrite Reumatoide/imunologia , Autoanticorpos/imunologia , Síndrome de Sjogren/imunologia , Vimentina/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Especificidade de Anticorpos/imunologia , Autoanticorpos/sangue , Feminino , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade , Peptídeos/sangue , Peptídeos/imunologia , Adulto Jovem
19.
Methods Mol Biol ; 1748: 37-47, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29453563

RESUMO

Immunohistochemistry (IHC) on formalin-fixed paraffin-embedded tissue specimens is a widely used laboratory technique that allows the demonstration and the direct microscopical observation of antigens within tissue sections by means of specific antibodies. IHC is one the best tools to define the immunophenotype of a cell during maturation or neoplastic transformation.To investigate the immunophenotype of postnatal rabbit Sertoli cell, from neonatal to adult age, in this chapter, the immunohistochemical protocol described is one of the most common: the avidin-biotin complex (ABC) method.


Assuntos
Imuno-Histoquímica/métodos , Células de Sertoli/citologia , Células de Sertoli/metabolismo , Animais , Animais Recém-Nascidos , Avidina/metabolismo , Biotina/metabolismo , Células Cultivadas , Masculino , Inclusão em Parafina , Coelhos , Vimentina/imunologia , Vimentina/metabolismo
20.
Am J Transplant ; 18(7): 1626-1635, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29316217

RESUMO

Long-term success of heart transplantation is hindered by humoral and cell-mediated immune responses. We studied preexisting antibodies to cardiac self-antigens, myosin and vimentin, and exosomes induced by antibodies to self-antigens in eliciting immune responses to cardiac grafts. After syngeneic heterotopic murine heart transplantation, rabbit anti-myosin or normal rabbit immunoglobulin was administered at day 0 or 7. Sera were collected after heartbeat cessation, cellular infiltration was analyzed, and exosomes were isolated from sera. Histopathologic examination of the controls' transplanted hearts demonstrated normal architecture, and their sera demonstrated neither antibodies to self-antigens nor exosomes expressing self-antigens. Administration of antibodies to cardiac myosin immediately posttransplantation (day 0) but not on day 7 triggered graft failure on day 7, and histopathologic examination revealed marked cellular infiltration with neutrophils and lymphocytes. Histopathologic examination of rejected hearts also demonstrated myocyte damage as sera had increased antibodies to myosin and vimentin and development of exosomes expressing self-antigens. Administration of exosomes isolated from failed grafts containing self-antigens induced graft dysfunction; exosomes isolated from stable mice did not induce graft failure. Antibodies to self-antigens can induce exosomes containing self-antigens, initiating an immune response and causing graft failure after cardiac transplantation.


Assuntos
Autoantígenos/imunologia , Miosinas Cardíacas/imunologia , Exossomos/imunologia , Rejeição de Enxerto/etiologia , Transplante de Coração/efeitos adversos , Isoanticorpos/imunologia , Vimentina/imunologia , Animais , Autoantígenos/metabolismo , Miosinas Cardíacas/metabolismo , Exossomos/metabolismo , Rejeição de Enxerto/metabolismo , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto/imunologia , Isoanticorpos/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Doadores de Tecidos , Transplante Isogênico , Vimentina/metabolismo
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