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2.
Z Rheumatol ; 82(1): 31-37, 2023 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-36053333

RESUMO

International guidelines recommend involving various professions and disciplines at an early stage in the event of chronic back pain. In connection with this, terms such as multiprofessional or interprofessional interventions are often mentioned without a uniform idea of what they mean. This article is intended to provide an overview of multiprofessional interventions for patients with chronic back pain and the integration into a meaningful interdisciplinary and interprofessional multimodal treatment concept. This is illustrated in a biopsychosocial pillar model, which should be pursued for each patient individually.


Assuntos
Dor nas Costas , Dor Crônica , Humanos , Dor nas Costas/diagnóstico , Dor nas Costas/terapia , Dor nas Costas/psicologia , Terapia Combinada , Dor Crônica/diagnóstico , Dor Crônica/terapia
3.
Vaccine ; 38(51): 8055-8063, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-33187767

RESUMO

Vaccines prevent infectious diseases, but vaccination is not without risk and adverse events are reported although they are more commonly reported for biologicals than for vaccines. Vaccines and biologicals must undergo vigorous assessment before and after licensure to minimise safety concerns. Potential safety concerns should be identified as early as possible during the development for vaccines and biologicals to minimize investment risk. State-of-the art tools and methods to identify safety concerns and biomarkers that are predictive of clinical outcomes are indispensable. For vaccines and adjuvant formulations, systems biology approaches, supported by single-cell microfluidics applied to translational studies between preclinical and clinical studies, could improve reactogenicity and safety predictions. Next-generation animal models for clinical assessment of injection-site reactions with greater relevance for target human population and criteria to define the level of acceptability of local reactogenicity at vaccine injection sites in pre-clinical animal species should be assessed. Advanced in silico machine-learning-based analytics, species-specific cell or tissue expression, receptor occupancy and kinetics and cell-based assays for functional activity are needed to improve pre-clinical safety assessment of biologicals. The in vitro MIMIC® system could be used to compliment preclinical and clinical studies for assessing immune-toxicity, immunogenicity, immuno-inflammatory and mode of action of biologicals and vaccines. Sanofi Pasteur brought together leading experts in this field to review the state-of-the-art at a unique 'Safety Biomarkers Symposium' on 28-29 November 2017. Here we summarise the proceedings of this symposium. This unique scientific meeting confirmed the importance for institutions and industrial organizations to collaborate to develop tools and methods needed for predicting reactogenicity and immune-inflammatory reactions to vaccines and biologicals, and to develop more accuracy, reliability safety biomarkers, to inform decisions on the attrition or advancement of vaccines and biologicals.


Assuntos
Produtos Biológicos , Vacinas , Animais , Produtos Biológicos/efeitos adversos , Biomarcadores , França , Humanos , Reprodutibilidade dos Testes , Vacinas/efeitos adversos
5.
Praxis (Bern 1994) ; 109(9): 687-692, 2020 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-32635850

RESUMO

CME-Rheuma 21: Precision Medicine - Synovial Biopsy in Rheumatology Abstract. Synovial biopsy is increasingly performed in the medicine of the musculoskeletal system. On the one hand it allows the in-depth diagnosis of unclear arthritides. On the other hand, there is an increasing body of publications showing that histology, immunohistochemistry and RNA analysis of synovial tissue may lead to subclassifications within rheumatoid arthritis. This in turn may have predictive value for the treatment response. We herein give a short overview of the joint biopsy technique, the basic evaluation of biopsy samples and the prospects of synovial biopsy.


Assuntos
Reumatologia , Sinovite , Biópsia , Humanos , Medicina de Precisão , Membrana Sinovial , Sinovite/diagnóstico
6.
MAbs ; 11(8): 1402-1414, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31526159

RESUMO

High specificity accompanied with the ability to recruit immune cells has made recombinant therapeutic antibodies an integral part of drug development. Here we present a generic approach to generate two novel IgG-derived antibody formats that are based on a modification of the CrossMab technology. MoAbs harbor two heavy chains (HCs) resulting in one binding entity and one fragment crystallizable region (Fc), whereas DuoMabs are composed of four HCs harboring two binding entities and two Fc regions linked at a disulfide-bridged hinge. The latter bivalent format is characterized by avidity-enhanced target cell binding while simultaneously increasing the 'Fc-load' on the surface. DuoMabs were shown to be producible in high yield and purity and bind to surface cells with affinities comparable to IgGs. The increased Fc load directed at the surface of target cells by DuoMabs modulates their antibody-dependent cell-mediated cytotoxicity competency toward target cells, making them attractive for applications that require or are modulated by FcR interactions.


Assuntos
Anticorpos Biespecíficos/imunologia , Anticorpos Monoclonais/imunologia , Citotoxicidade Celular Dependente de Anticorpos , Fragmentos Fc das Imunoglobulinas/imunologia , Imunoglobulina G/imunologia , Anticorpos Biespecíficos/química , Anticorpos Monoclonais/química , Células HEK293 , Humanos , Fragmentos Fc das Imunoglobulinas/química , Imunoglobulina G/química
7.
Arthritis Res Ther ; 21(1): 175, 2019 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-31319889

RESUMO

OBJECTIVE: Primary Sjögren syndrome (pSS) is characterized by T and B cell infiltration of exocrine glands. The cysteine protease cathepsin S (CatS) is crucially involved in MHCII processing and T cell stimulation, and elevated levels have been found in patients with RA, psoriasis and pSS. However, little is known about the functional characteristics and mechanisms of SS-A- and SS-B-specific T cells in pSS patients. We herein investigated the inhibition of CatS activity in different biocompartments of pSS patients including antigen-specific T cell responses. METHODS: Ex vivo CatS activity was assessed in tears, plasma and saliva of 15 pSS patients and 13 healthy controls (HC) and in the presence or absence of the specific CatS inhibitor RO5459072. In addition, antigen (SS-A (60kD), SS-B, influenza H3N2, tetanus toxoid and SEB)-specific T cell responses were examined using ex vivo IFN-γ/IL-17 Dual ELISPOT and Bromdesoxyuridin (BrdU) proliferation assays in the presence or absence of RO5459072. Supernatants were analysed for IL-1ß, IL-6, IL-10, TNF-α, IL-21, IL-22 and IL-23, using conventional ELISA. RESULTS: CatS activity was significantly elevated in tear fluid, but not other biocompartments, was inversely associated with exocrinic function in pSS patients and could significantly be suppressed by RO5459072. Moreover, CatS inhibition by RO5459072 led to strong and dose-dependent suppression of SS-A/SS-B-specific T cell effector functions and cytokine secretion by CD14+ monocytes. However, RO5459072 was incapable of suppressing SS-A/SS-B-induced secretion of cytokines in CD14+ monocytes when T cells were absent, confirming a CatS/MHCII-mediated mechanism of suppression. CONCLUSION: CatS activity in tear fluid seems to be a relevant biomarker for pSS disease activity. Conversely, CatS inhibition diminishes T cell and associated monokine responses towards relevant autoantigens in pSS. Thus, CatS inhibition may represent a promising novel treatment strategy in pSS.


Assuntos
Catepsinas/antagonistas & inibidores , Inibidores de Cisteína Proteinase/farmacologia , Pirazóis/farmacologia , Pirrolidinas/farmacologia , Saliva/imunologia , Síndrome de Sjogren/imunologia , Lágrimas/imunologia , Adulto , Idoso , Autoantígenos/imunologia , Autoantígenos/metabolismo , Catepsinas/imunologia , Catepsinas/metabolismo , Proliferação de Células/efeitos dos fármacos , Citocinas/imunologia , Citocinas/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Monócitos/metabolismo , Ribonucleoproteínas/imunologia , Ribonucleoproteínas/metabolismo , Saliva/enzimologia , Síndrome de Sjogren/sangue , Síndrome de Sjogren/enzimologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Lágrimas/enzimologia , Antígeno SS-B
10.
Arthritis Res Ther ; 19(1): 245, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-29096690

RESUMO

BACKGROUND: Toll-like receptors (TLRs) and macrophages play an important role in rheumatoid arthritis (RA). Currently, it is not clear whether inflammatory M1 or anti-inflammatory M2 predominate among the resident macrophages in the synovium. In the present study, we set out to investigate the impact of TLR stimulation on monocyte-derived M1 and M2 macrophage function and phenotype by mimicking the exposure to abundant TLR agonists as occurs in the context of RA. The response of macrophage subsets to TLR2 and TLR4 activation was evaluated on cluster of differentiation (CD) marker profile; cytokine secretion; gene expression; and NF-κB, interferon regulatory factors 3 and 7 (IRF3/7), and mitogen-activated protein kinase (MAPK) activation. METHODS: Human monocytes were isolated from peripheral blood of healthy individuals and patients with RA and differentiated into M1-like and M2-like macrophages by granulocyte-macrophage colony-stimulating factor (GM-CSF) and macrophage colony-stimulating factor (M-CSF), respectively. Cells were either (1) stimulated with TLR ligands Pam3 or lipopolysaccharide (LPS) or (2) classically activated via interferon (IFN)-γ/LPS. Cytokine production was measured by enzyme-linked immunosorbent assay, and gene expression was measured by qPCR. Cells were stained for CD markers and analyzed by fluorescence-activated cell sorting. NF-κB, IRF3/7, and MAPKs were detected by Western blotting. RESULTS: Monocyte-derived macrophages of healthy donors (HD) or patients with RA displayed comparable subset-specific phenotypes upon exposure to TLR agonists. CD14 and CD163 marker expression on M2 macrophages did not change upon TLR2 and TLR4 engagement. By contrast, M2 gene markers HMOX1, FOLR2, and SLC40A1 were decreased. Importantly, M2 macrophages derived from HD or patients with RA showed both a decreased ratio of interleukin (IL)-10/IL-6 and IL-10/IL-8 upon stimulation with TLR2 ligand Pam3 compared with TLR4 ligand LPS. Gene expression of TLR2 was increased, whereas TLR4 expression was decreased, by TLR ligand stimulation. MAPKs p38, extracellular signal-regulated kinase 1/2, and c-Jun N-terminal kinase were activated more strongly in M2 than in M1 macrophages by Pam3 or LPS. CONCLUSIONS: We show that the anti-inflammatory activity of M2 macrophages is reduced in the presence of abundant TLR2 ligands without significant changes in cell surface markers. Thus, the classical M1/M2 paradigm based on cellular markers does not apply to macrophage functions in inflammatory conditions such as RA.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Monócitos/efeitos dos fármacos , Receptor 2 Toll-Like/agonistas , Artrite Reumatoide/genética , Artrite Reumatoide/metabolismo , Artrite Reumatoide/patologia , Western Blotting , Diferenciação Celular/genética , Células Cultivadas , Citocinas/metabolismo , Expressão Gênica/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Lipopolissacarídeos/farmacologia , Fator Estimulador de Colônias de Macrófagos/farmacologia , Macrófagos/classificação , Macrófagos/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Monócitos/citologia , Monócitos/metabolismo , NF-kappa B/metabolismo , Fenótipo , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo
11.
J Toxicol Sci ; 41(4): 523-31, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27432238

RESUMO

After the life-threatening cytokine release syndrome (CRS) occurred in the clinical study of the anti-CD28 monoclonal antibody (mAb) TGN1412, in vitro cytokine release assays using human blood cells have been proposed for non-clinical evaluation of the potential risk of CRS. Two basic assay formats are frequently used: human peripheral blood mononuclear cells (PBMC) with immobilized mAbs, and whole blood with aqueous mAbs. However, the suitability of the whole blood cytokine assay (WBCA) has been questioned, because an unrealistically large sample size would be required to detect the potential risk of CRS induced by TGN1412, which has low sensitivity. We performed a WBCA using peripheral blood obtained from 68 healthy volunteers to compare two high risk mAbs, the TGN1412 analogue anti-CD28 superagonistic mAb (CD28SA) and the FcγR-mediated alemutuzumab, with a low risk mAb, panitumumab. Based on the cytokine measurements in this study, the sample size required to detect a statistically significant increase in cytokines with 90% power and 5% significance was determined to be n = 9 for CD28SA and n = 5 for alemtuzumab. The most sensitive marker was IL-8. The results suggest that WBCA is a practical test design that can warn of the potential risk of FcγR-mediated alemtuzumab and T-cell activating CD28SA but, because there was apparently a lower response to CD28SA, it cannot be used as a risk-ranking tool. WBCA is suggested to be a helpful tool for identifying potential FcγR-mediated hazards, but further mechanistic understanding of the response to CD28SA is necessary before applying it to T cell-stimulating mAbs.


Assuntos
Anticorpos Monoclonais Humanizados/toxicidade , Anticorpos Monoclonais/toxicidade , Células Sanguíneas/efeitos dos fármacos , Citocinas/sangue , Testes de Toxicidade/métodos , Alemtuzumab , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados/administração & dosagem , Biomarcadores/sangue , Células Sanguíneas/imunologia , Células Sanguíneas/metabolismo , Humanos , Infusões Parenterais , Panitumumabe , Reprodutibilidade dos Testes , Medição de Risco
13.
Ther Umsch ; 73(3): 147-52, 2016.
Artigo em Alemão | MEDLINE | ID: mdl-27008447

RESUMO

Gout is the most frequent arthritis worldwide with increasing prevalence in industrialized countries and massive socioeconomic consequences. The knowledge regarding the pathomechanisms which lead to arthritis has substantially increased during the last decade. Consistently, new therapeutic approaches and substances appear at the horizon. This review covers aspects of clinical presentation, diagnosis and current treatment. The pathomechanisms leading to NLRP3 inflammasome activation and IL-1beta secretion are reviewed in detail. Finally, selected new therapeutic targets and substances are discussed.


Assuntos
Artrite Gotosa/tratamento farmacológico , Artrite Gotosa/etiologia , Supressores da Gota/uso terapêutico , Gota/tratamento farmacológico , Gota/etiologia , Artrite Gotosa/diagnóstico , Aprovação de Drogas , Gota/diagnóstico , Supressores da Gota/efeitos adversos , Humanos , Pesquisa , Suíça
15.
Swiss Med Wkly ; 144: w13937, 2014 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-24652684

RESUMO

In humans, hantaviruses can cause haemorrhagic fever with renal syndrome (HFRS) or hantavirus cardiopulmonary syndrome (HCPS). Currently it is estimated that 150,000 to 200,000 cases of hantavirus disease occur each year, the majority being reported in Asia. However, human hantavirus infections are increasingly reported in the Americas and Europe. Although many of the underlying pathogenic mechanisms still remain unclear, recent evidence rather argues against a purely immune-mediated pathophysiology of human disease. Despite the high morbidity and case-fatality rates of HFRS and HCPS, respectively, no vaccine or drug is currently proven to be preventive or therapeutic. This review summarises clinical features and current epidemiological findings, as well as concepts regarding the immunology, pathogenesis and intervention strategies of human hantaviral diseases.


Assuntos
Síndrome Pulmonar por Hantavirus , Febre Hemorrágica com Síndrome Renal , Animais , Síndrome Pulmonar por Hantavirus/diagnóstico , Síndrome Pulmonar por Hantavirus/tratamento farmacológico , Síndrome Pulmonar por Hantavirus/epidemiologia , Síndrome Pulmonar por Hantavirus/imunologia , Febre Hemorrágica com Síndrome Renal/diagnóstico , Febre Hemorrágica com Síndrome Renal/tratamento farmacológico , Febre Hemorrágica com Síndrome Renal/epidemiologia , Febre Hemorrágica com Síndrome Renal/imunologia , Humanos
16.
Toxicol Sci ; 138(2): 333-43, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24385420

RESUMO

Vascular leakage is a serious side effect of therapies based on monoclonal antibodies or cytokines which may lead to life-threatening situations. With the steady increase of new drug development programs for large molecules, there is an urgent need for reliable tools to assess this potential liability of new medicines in a rapid and cost-effective manner. Using human umbilical vein endothelial cells (HUVECs) as a model for endothelium, we established an impedance-based assay measuring the integrity of the endothelial cell monolayer in real time. We could demonstrate that the HUVEC monolayer in our system was a relevant model as cells expressed major junctional proteins known to be responsible for maintaining tightness as well as receptors targeted by molecules known to induce vascular leakage in vivo. We assessed the time-dependent loss of barrier function using impedance and confirmed that signals obtained corresponded well to those from standard transwell assays. We assayed a series of reference molecules which led to the expected change of barrier integrity. A nonspecific cytotoxic effect could be excluded by using human fibroblasts as a nonresponder cell line. Finally, we could show reversibility of vascular permeability induced by histamine, IL-1ß, or TNF-α by coincubation with established antagonists, further demonstrating relevance of this new model. Taken together, our results suggest that impedance in combination with HUVECs as a specific model can be applied to assess clinically relevant vascular leakage on an in vitro level.


Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Drogas em Investigação/toxicidade , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Modelos Biológicos , Testes de Toxicidade/métodos , Impedância Elétrica , Células Endoteliais/patologia , Endotélio Vascular/patologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Fatores de Tempo , Testes de Toxicidade/instrumentação
17.
J Pharmacol Toxicol Methods ; 68(2): 231-239, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23280407

RESUMO

INTRODUCTION: In 2006 the anti-CD28 superagonistic IgG4 TGN1412, having passed pre-clinical safety screens, caused a severe 'cytokine storm' in 6 healthy volunteers. Others have shown that for TGN1412 to induce an inflammatory signal in human peripheral blood mononuclear cells (PBMCs) or in human diluted blood, endothelial cells or bound monoclonal antibody (mAb) is required as part of a bioassay complex. These types of protocols rely on different donor cells and therefore have limitations as bioassays for pre-clinical testing. METHODS: We performed studies using human PBMC/endothelial cell co-cultures, whole blood/endothelial cell co-cultures and human whole blood alone. We bracketed responses of a CD28 superagonist antibody with mAbs against CD52 (alemtuzumab, MabCampath-1H) or epidermal growth factor receptor (cetuximab, Erbitux) and with the immunostimulant lipopolysaccharide. We detected cytokine responses at the level of protein release (using ELISAs and Luminex assays) and gene induction (using real-time PCR arrays). RESULTS: Here we confirm that IL-8 release was induced in a mixed endothelial cell-PBMC system by the anti-CD28 mAb. We go on to show that an alemtuzumab and an anti-CD28 mAb, but not cetuximab induced the release of a range of cytokines including IL-8, IL-6, IFNγ, IL-2 and IL10 after 24h and induced cytokine gene induction after 1h. Co-cultures of whole blood and HUVECS showed larger variability but no superiority over whole blood alone at a range of time points (0.5-48h). DISCUSSION: We suggest that, whilst limitations exist, human blood-based in vitro assays may prove useful in assessing the potential of mAbs and other biotherapeutics to cause release of cytokines in humans.


Assuntos
Anticorpos Monoclonais Humanizados/imunologia , Antígenos CD/imunologia , Antígenos de Neoplasias/imunologia , Antígenos CD28/imunologia , Citocinas/metabolismo , Glicoproteínas/imunologia , Alemtuzumab , Anticorpos Monoclonais Humanizados/farmacologia , Bioensaio/métodos , Antígeno CD52 , Cetuximab , Técnicas de Cocultura , Citocinas/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Células Endoteliais da Veia Umbilical Humana/imunologia , Humanos , Leucócitos Mononucleares/imunologia , Masculino , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Tempo
18.
PLoS One ; 7(10): e46779, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23056449

RESUMO

BACKGROUND: Alfa-interferons (IFNα2a, IFNα2b, 40KDa-PEGIFNα2a and 12KDa-PEGIFNα2b) are effective treatments for chronic hepatitis C infection. However, their usage has been associated with a variety of adverse events, including interstitial pneumonitis and pulmonary arterial hypertension. Although rare, these adverse events can be severe and potentially life-threatening, emphasizing the need for simple biomarkers of IFN-induced lung toxicity. METHODS: Human lung microvascular endothelial cells (HLMVEC), human pulmonary artery smooth muscle (HPASM) cells and A549 cells were grown under standard conditions and plated into 96- or 6-well plates. Cells were stimulated with various concentrations of different IFNs in hydrocortisone-free medium. After 24 and 48 hours, IP10 and ET-1 were measured by ELISA in conditioned medium. In a second set of experiments, cells were pre-treated with tumour necrosis factor-α (TNF-α) (10 ng/mL). RESULTS: IFNα2a, IFNα2b, 40KDa-PEGIFNα2a and 12KDa-PEGIFNα2b, but not IFNλ, induced IP10 (CXCL10) release and increased IP10 gene induction in HLMVEC. In addition, all four IFNα preparations induced IP10 release from HPASM cells and A549 cells pre-treated with TNFα. In each of these cell types, 40KDa-PEGIFNα2a was significantly less active than the native forms of IFNα2a, IFNα2b or 12KDa-PEGIFNα2b. Similarly, IFNα2a, IFNα2b and 12KDa-PEGIFNα2b, but not 40KDa-PEGIFNα2a, induced endothelin (ET)-1 release from HPASM cells. CONCLUSIONS: Consistent with other interstitial pulmonary diseases, both IP10 and ET1 may serve as markers to monitor IFN-induced lung toxicity in patients. In addition, both markers may also serve to help characterize the risk associated with IFNα preparations to induce lung toxicity.


Assuntos
Endotelina-1/metabolismo , Interferon-alfa/farmacologia , Pulmão/citologia , Receptores de Citocinas/metabolismo , Linhagem Celular , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Interferon alfa-2 , Proteínas Recombinantes/farmacologia
19.
PLoS Pathog ; 6(2): e1000779, 2010 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-20174562

RESUMO

In man, infection with South American Andes virus (ANDV) causes hantavirus cardiopulmonary syndrome (HCPS). HCPS due to ANDV is endemic in Southern Chile and much of Argentina and increasing numbers of cases are reported all over South America. A case-fatality rate of about 36% together with the absence of successful antiviral therapies urge the development of a vaccine. Although T-cell responses were shown to be critically involved in immunity to hantaviruses in mouse models, no data are available on the magnitude, specificity and longevity of ANDV-specific memory T-cell responses in patients. Using sets of overlapping peptides in IFN-gamma ELISPOT assays, we herein show in 78 Chilean convalescent patients that Gn-derived epitopes were immunodominant as compared to those from the N- and Gc-proteins. Furthermore, while the relative contribution of the N-specific response significantly declined over time, Gn-specific responses remained readily detectable ex vivo up to 13 years after the acute infection. Tetramer analysis further showed that up to 16.8% of all circulating CD3(+)CD8(+) T cells were specific for the single HLA-B*3501-restricted epitope Gn(465-473) years after the acute infection. Remarkably, Gn(465-473)-specific cells readily secreted IFN-gamma, granzyme B and TNF-alpha but not IL-2 upon stimulation and showed a 'revertant' CD45RA(+)CD27(-)CD28(-)CCR7(-)CD127(-) effector memory phenotype, thereby resembling a phenotype seen in other latent virus infections. Most intriguingly, titers of neutralizing antibodies increased over time in 10/17 individuals months to years after the acute infection and independently of whether they were residents of endemic areas or not. Thus, our data suggest intrinsic, latent antigenic stimulation of Gn-specific T-cells. However, it remains a major task for future studies to proof this hypothesis by determination of viral antigen in convalescent patients. Furthermore, it remains to be seen whether Gn-specific T cells are critical for viral control and protective immunity. If so, Gn-derived immunodominant epitopes could be of high value for future ANDV vaccines.


Assuntos
Antígenos Virais/imunologia , Linfócitos T CD8-Positivos/imunologia , Epitopos de Linfócito T/imunologia , Infecções por Hantavirus/imunologia , Memória Imunológica/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Separação Celular , Chile , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Orthohantavírus/imunologia , Humanos , Epitopos Imunodominantes/imunologia
20.
J Med Virol ; 80(11): 1947-51, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18814258

RESUMO

Hantavirus Cardiopulmonary Syndrome (HCPS) due to Andes virus (ANDV) is endemic in Chile and Argentina and currently demonstrates a case-fatality rate of 37% in humans. By contrast to the chronically infected rodents, it is believed that ANDV in humans is cleared during the acute phase. Moreover, to date, both magnitude and quality of human T-cell responses during ANDV infection and clearance are unknown. Using IFN-gamma and granzyme B ELISPOT assays as well as flow cytometry, we prospectively studied the ANDV-specific T-cell responses in a 56-year-old convalescing survivor of severe HCPS, whose blood cells remained PCR-positive for ANDV-RNA until day 53 after hospital admission, that is, 67 days after infection and 42 days after discharge. PCR-negativity was closely related to the increase and function of (Gn(46-60))-specific IFN-gamma(+) granzyme B(+) CD8(+) T-cells, but not to neutralizing antibody titers. Concurrently, the phenotype of CD45RA(+)CCR7(-) Gn(46-60)-specific T-cells shifted from a CD28(-)CD27(+) "intermediate" to a CD28(-) CD27(-) "late" effector memory beyond day 53 after hospital admission. This is the first report that shows that ANDV can persist in the human hosts for more than 2 months. Moreover, the kinetics of T-cell responses during ANDV clearance may indicate a major role of T-cells for clearance of ANDV and human immunity to this pathogen.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Síndrome Pulmonar por Hantavirus/imunologia , Orthohantavírus/imunologia , Anticorpos Antivirais/sangue , Células Cultivadas , Chile , Granzimas/metabolismo , Humanos , Interferon gama/metabolismo , Pessoa de Meia-Idade , Testes de Neutralização , Estudos Prospectivos , RNA Viral/sangue
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