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2.
J Mol Med (Berl) ; 99(1): 147-158, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33278000

RESUMO

HLA-B*57 affects the course of HIV infection. Under antiretroviral therapy, its effects cannot be explained by outstandingly efficient T cell responses alone but may also involve cells of innate immunity. Studying in vitro stimulation with Pam3CSK4, E. coli LPS-B5 and CpG-ODN-2216, we observed greater induction of IL-6/IL-1beta double-positive CD14+CD16++ monocytes as well as IFN-gamma-positive cytotoxic CD56highCD16neg NK cells in HLA-B*57- versus HLA-B*44-positive HIV patients, while TNF-alpha induction remained unchanged. Differences were not seen in the other monocyte and NK cell subsets or in HLA-matched healthy controls. Our findings show that, in virally suppressed HIV infection, HLA-B*57 is associated with enhanced responsiveness of inflammatory innate immune cells to TLR ligands, possibly contributing to increased vulnerability in sepsis. KEY MESSAGES: • HLA-B*57 is a host factor affecting clinical outcomes of HIV infection. • HLA-B*57 modifies inflammatory subsets of NK cells and monocytes in HIV infection. • In HLA-B*57-positive HIV patients TLR agonists induce enhanced IL-6/IL-1beta in monocytes. • NK cells from HLA-B*57 HIV patients release more IFN-gamma upon TLR costimulation. • HLA-B*57 is linked to enhanced inflammatory responsiveness to TLR ligands.


Assuntos
Infecções por HIV/imunologia , Antígenos HLA-B/imunologia , Células Matadoras Naturais/imunologia , Monócitos/imunologia , Linfócitos T/imunologia , Receptores Toll-Like/agonistas , Adulto , Idoso , Idoso de 80 Anos ou mais , Citocinas/imunologia , Feminino , Humanos , Imunidade Inata , Inflamação/imunologia , Células Matadoras Naturais/efeitos dos fármacos , Lipopeptídeos/farmacologia , Lipopolissacarídeos/farmacologia , Masculino , Pessoa de Meia-Idade , Monócitos/efeitos dos fármacos , Oligodesoxirribonucleotídeos/farmacologia , Linfócitos T/efeitos dos fármacos , Receptor Toll-Like 9/agonistas , Adulto Jovem
3.
Endosc Int Open ; 8(10): E1308-E1314, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33015332

RESUMO

Backround and study aims Duodenal cancer is the cancer most often seen in patients with familial adenomatous polyposis (FAP) who have undergone risk-reducing colonic surgery. Almost all patients with FAP eventually develop duodenal adenomas and risk for duodenal cancer is up to 12 % with poor prognosis. In addition, there is a rising concern regarding increased gastric cancer risk in patients with FAP. Our aim was to enhance polyp detection by using CE (CE) with the application of indigo carmine dye. Patient and methods We conducted a prospective, blinded study of patients with FAP undergoing endoscopic examination of the upper gastrointestinal tract. First, a standard white-light examination (WLE) was done followed by an examination performed by an endoscopist who was blinded to the previous examination, using chromoendoscopy (CE) (0.4 % indigo carmine dye). Results Fifty patients were included in the study. Using WLE, a median number of 13 adenomas (range 0-90) was detected compared to 23 adenomas/patient (range 0-150; P  < 0.0001) detected after staining, leading to a higher Spigelman stage in 16 patients (32 %; P  = 0.0003). CE detected significantly more larger adenomas (> 10 mm) than WLE (12 vs. 19; P  = 0.0391). In the gastric antral region, a median number of 0 adenomas (range 0-6) before and 0.5 adenomas (range 0-7) after staining ( P  = 0.0025) were detected. Conclusion This prospective endoscopic trial, to our knowledge the largest in patients with FAP, showed a significant impact of CE on adenoma detection and therapeutic management in the upper gastrointestinal tract. This leads to more intensive surveillance intervals.

4.
Life Sci ; 260: 118400, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32918975

RESUMO

Clinical manifestations of COVID-19 affect many organs, including the heart. Cardiovascular disease is a dominant comorbidity and prognostic factors predicting risk for critical courses are highly needed. Moreover, immunomechanisms underlying COVID-induced myocardial damage are poorly understood. OBJECTIVE: To elucidate prognostic markers to identify patients at risk. RESULTS: Only patients with pericardial effusion (PE) developed a severe disease course, and those who died could be identified by a high CD8/Treg/monocyte ratio. Ten out of 19 COVID-19 patients presented with PE, 7 (78%) of these had elevated APACHE-II mortality risk-score, requiring mechanical ventilation. At admission, PE patients showed signs of systemic and cardiac inflammation in NMR and impaired cardiac function as detected by transthoracic echocardiography (TTE), whereas parameters of myocardial injury e.g. high sensitive troponin-t (hs-TnT) were not yet increased. During the course of disease, hs-TnT rose in 8 of the PE-patients above 16 ng/l, 7 had to undergo ventilatory therapy and 4 of them died. FACS at admission showed in PE patients elevated frequencies of CD3+CD8+ T cells among all CD3+ T-cells, and lower frequencies of Tregs and CD14+HLA-DR+-monocytes. A high CD8/Treg/monocyte ratio predicted a severe disease course in PE patients, and was associated with high serum levels of antiviral cytokines. By contrast, patients without PE and PE patients with a low CD8/Treg/monocyte ratio neither had to be intubated, nor died. CONCLUSIONS: PE predicts cardiac injury in COVID-19 patients. Therefore, TTE should be performed at admission. Immunological parameters for dysfunctional antiviral immunity, such as the CD8/Treg/monocyte ratio used here, supports risk assessment by predicting poor prognosis.


Assuntos
Betacoronavirus/isolamento & purificação , Biomarcadores/análise , Infecções por Coronavirus/mortalidade , Traumatismo por Reperfusão Miocárdica/diagnóstico , Traumatismo por Reperfusão Miocárdica/mortalidade , Miocárdio/patologia , Pneumonia Viral/mortalidade , Medição de Risco/métodos , Idoso , COVID-19 , Infecções por Coronavirus/complicações , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Feminino , Alemanha/epidemiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Traumatismo por Reperfusão Miocárdica/epidemiologia , Traumatismo por Reperfusão Miocárdica/virologia , Miocárdio/metabolismo , Pandemias , Pneumonia Viral/complicações , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Prognóstico , Fatores de Risco , SARS-CoV-2 , Taxa de Sobrevida
6.
Genes Immun ; 14(5): 286-90, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23594959

RESUMO

IL28B polymorphisms strongly predict spontaneous and treatment-induced clearance of hepatitis C virus (HCV) infection. A recent study proposed a 32-base pair deletion in the CC-chemokine receptor 5 (CCR5) gene (CCR5-Δ32) interacting with the IL28B polymorphisms to influence spontaneous HCV clearance. The aim of this study was to clarify the role of CCR5-Δ32 in treatment-induced clearance of chronic hepatitis C (CHC). A cross-sectional cohort of 813 Caucasian patients with CHC genotype 1 (365 responders and 448 non-responders) who had received standard of care dual therapy with interferon (IFN)-α and ribavirin (RBV) was genotyped for the CCR5-Δ32 and IL28B polymorphisms to examine their interaction with respect to treatment response. CCR5-Δ32 did not influence treatment-induced recovery to IFN-α/RBV in CHC, and did not improve prediction of sustained virological response in the context of the IL28B polymorphisms in a multivariate model. CCR5-Δ32 homozygotes were significantly more frequent in those with CHC than healthy controls in the European cohorts (2.9% vs 0.4%, P<0.0001), but not in Australians of European ancestry. In conclusion, CCR5-Δ32 does not influence treatment response in the context of IL28B polymorphisms. Although CCR5-Δ32 may affect viral clearance within closely controlled geographical and genetic environments, we found no effect in larger cohorts treated with dual therapy.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interleucinas/genética , Polimorfismo de Nucleotídeo Único , Receptores CCR5/genética , Deleção de Sequência , Adulto , Austrália , Sequência de Bases , Estudos de Coortes , Estudos Transversais , Quimioterapia Combinada , Epistasia Genética , Europa (Continente) , Feminino , Genótipo , Hepatite C Crônica/etnologia , Hepatite C Crônica/genética , Humanos , Interferon-alfa/uso terapêutico , Interferons , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Ribavirina/uso terapêutico , Resultado do Tratamento , População Branca/genética
8.
Eur J Med Res ; 16(3): 101-7, 2011 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-21486722

RESUMO

OBJECTIVES: To estimate the cancer risk of HIV-infected patients in the HAART era with respect to a general reference population and to determine risk factors for malignancy. METHODS: Long term (1996-2009) cancer incidence of the Bonn single centre HIV cohort was compared to the incidence of the reference population of Saarland using standardized incidence ratios (SIR). Poisson regression analysis was used to identify predictors of cancer risk. RESULTS: 1,476 patients entered the cohort, enabling 8,772 person years of observation. 121 tumours in 114 patients, 7 in-situ and 114 invasive cancers, were identified. Malignancies associated with infectious agents such as Kaposi sarcoma (SIRs: male: 5,683; female: 277), non-Hodgkin lymphoma (SIRs male: 35; female: 18), anal cancer (SIRs male: 88; female: 115) as well a cervical carcinoma (SIR female: 4) and Hodgkin?s disease (SIR male: 39) and liver cancer (SIR male: 18) were substantially more frequent in HIV-infected patients than in the general population (p< 0.001, each), whereas all other types of cancer were not increased. Poisson regression identified HAART (incidence rate ratio IRR (95% CI): 0.28 (0.19-0.41), p<0.001), CD4 count (IRR per 100 cells/µl increase: 0.66 (0.57-0.76), p<0.001), hepatitis B (IRR: 2.15 (1.10-4.20), p = 0.046) and age (IRR per 10 year increase: 1.23 (1.03 - 1.46), p = 0.023) as independent predictors for the occurrence of any type of cancer. CONCLUSIONS: HAART and preserved CD4 cells preferentially reduce the risk of malignancies associated with oncogenic infections.


Assuntos
Infecções por HIV/complicações , Imunocompetência , Neoplasias/complicações , Oncogenes , Adolescente , Adulto , Idoso , Contagem de Linfócito CD4 , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética , Infecções por HIV/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/genética , Neoplasias/imunologia , Fatores de Risco , Adulto Jovem
9.
HIV Med ; 12(8): 487-93, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21375685

RESUMO

OBJECTIVES: The C allele of the single nucleotide polymorphism rs12979860, located near the interleukin-28B (IL-28B) gene, has a strong impact on hepatitis C virus (HCV) treatment response, as well as on spontaneous viral clearance. In patients with chronic hepatitis C (CHC), genotype CC carriers harbour HCV genotype 3 more commonly than those with non-CC genotypes. The aim of this study was to compare the HCV genotype distributions, according to IL-28B genotype, in HIV-infected patients with CHC and those with acute hepatitis C (AHC). METHODS: The rs12979860 genotype was determined by polymerase chain reaction (PCR) in two subpopulations of HIV-infected patients. The first consisted of 80 German patients with AHC. The second consisted of 476 patients with CHC, belonging to one German and two Spanish cohorts. RESULTS: In the AHC group, 31 (81.6%) rs12979860 CC carriers were infected with HCV genotype 1 or 4 vs. 32 (76.2%) among non-CC carriers (P=0.948). In patients with CHC, among those with the CC genotype, 119 (54.6%) were infected with HCV genotype 1 or 4 and 99 (45.4%) with genotype 2 or 3, whereas in the subset with non-CC genotypes, 200 (77.5%) harboured HCV genotype 1 or 4 and 58 (22.5%) genotype 2 or 3 (P<0.001). CONCLUSIONS: Among HIV-infected patients with CHC, those bearing the IL-28B genotype CC were more commonly infected with genotype 3 than subjects with non-CC genotypes, whereas in HIV-infected subjects with AHC this finding was not obtained. These results strongly suggest that the protective effect of the CC genotype against evolution to CHC is mainly exerted in patients infected with HCV genotype 1 or 4.


Assuntos
Hepacivirus/genética , Hepatite C Crônica/virologia , Hepatite C/virologia , Interleucinas/genética , Adulto , Coinfecção , Feminino , Genótipo , Infecções por HIV/complicações , Infecções por HIV/virologia , Hepacivirus/classificação , Hepatite C/complicações , Hepatite C/genética , Hepatite C Crônica/complicações , Hepatite C Crônica/genética , Humanos , Interferons , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
10.
J Hepatol ; 55(5): 1010-6, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21356257

RESUMO

BACKGROUND & AIMS: Toll-like receptor (TLR) 2 and nucleotide-binding oligomerisation domain (NOD) 2 recognize distinct pathogen-associated molecular patterns (PAMS) on the cell surface and in the cytoplasm, respectively. Since they may contribute to susceptibility to spontaneous bacterial peritonitis (SBP), we studied the effects of TLR2 gene variants on susceptibility for SBP in relation to the previously reported NOD2 alleles. METHODS: Overall, 150 patients with liver cirrhosis and ascites were genotyped for TLR2 gene variants -16934 (rs4696480), Arg753Gln (rs5743708), Pro631His (rs5743704) and the TLR2 GT microsatellite polymorphism in intron 2. Patients were monitored for SBP over two years. TLR2 SNPs were identified by hybridization probe assays on a LightCycler system. Numbers of GT repeats were determined with an ABI310 sequencer and Genescan Analysis 2.1 software. RESULTS: Fifty two patients (35%) had SBP. Unlike the TLR2 Arg753Gln and Pro631His mutations, SBP was significantly more frequent in patients with the TLR2 -16934 TT genotype (38.5% vs. 15.3%; p = 0.002) and in carriers with two long tandem GT repeat alleles (>20) (53.8% vs. 25.5%; p = 0.001). A multivariate analysis confirmed TLR2 GT microsatellite polymorphism (OR = 3.8, p = 0.002) and NOD2 variants (OR = 3.3, p = 0.011) as independent predictors of SBP, and the simultaneous presence of both risk factors indicated a particularly high risk for SBP (OR = 11.3, p = 0.00002). CONCLUSIONS: Analogous to NOD2 risk variants, TLR2 polymorphisms indicate increased susceptibility toward SBP in cirrhotic patients with ascites, and the combination of the TLR2 GT microsatellite polymorphism with at least one NOD2 risk variant enables improved identification of patients with a high risk for SBP.


Assuntos
Infecções Bacterianas/genética , Predisposição Genética para Doença , Cirrose Hepática/complicações , Proteína Adaptadora de Sinalização NOD2/genética , Peritonite/genética , Receptor 2 Toll-Like/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Ascite/complicações , Infecções Bacterianas/microbiologia , Feminino , Genótipo , Humanos , Íntrons , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Análise Multivariada , Peritonite/microbiologia , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Curva ROC , Fatores de Risco , Adulto Jovem
11.
Eur J Med Res ; 13(2): 87-91, 2008 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-18424368

RESUMO

OBJECTIVES AND METHODS: Despite liver transplantation and advances in intensive care medicine fulminant hepatic failure [FHF] remains a life-threatening condition. Actual observations of the clinical course of these patients are rare. Therefore, we analyzed course of disease and survival in all patients treated for FHF at the University of Bonn between 1998 and 2004 and compared it to the patients treated for FHF during 1992-1997. RESULTS: 35 patients were treated for FHF during this period. FHF was viral induced in 13 patients (HBV n = 11, HAV n = 2), toxic in nine, cryptogenic in eleven and autoimmune and hyperthermia in one patient each. According to London- and/or Clichy criteria 16 patients were transplanted. Four of them died during the first year after transplantation due to infectious and hemorrhagic complications. Three patients died without liver-transplantation. All together, 1-year survival was 80%. When compared to patients with FHF analyzed in the period 1992-1997 numbers of patients with FHF in our centre had increased from 16 to 35 patients and 1-year survival improved from 67.5% to 80%. This improved survival was associated with a lower proportion of transplanted patients (45% versus 68%). CONCLUSIONS: These changes reflect advances in therapy of patients with FHF, which enables a greater proportion of patients to survive without the need for transplantation.


Assuntos
Falência Hepática Aguda/cirurgia , Transplante de Fígado/métodos , Adulto , Feminino , Seguimentos , Humanos , Falência Hepática Aguda/diagnóstico , Falência Hepática Aguda/mortalidade , Londres , Masculino , Pessoa de Meia-Idade , Prognóstico , Índice de Gravidade de Doença , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
12.
Int J Lab Hematol ; 29(6): 469-73, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17988304

RESUMO

To date little data exist about treatment of hematologic malignancies in patients with end-stage renal disease (ESRD). While administration of immunochemotherapy comprising the CD20-antibody rituximab is a well-established treatment strategy in patients with normal renal function, little information on safety and efficacy is available in the setting of ESRD. Here we describe for the first time a hemodialysis patient suffering from diffuse large B-cell Non-Hodgkin's lymphoma (DLBCL) who was treated with polychemotherapy (cyclophosphamide, doxorubicin, vincristine and prednisone) in combination with rituximab (R-CHOP). We observed no major adverse events and treatment resulted in a partial remission of the DLBCL. Thus, administration of R-CHOP may be considered as a safe therapeutic option in this setting. Of note, this patient had a previous history of hairy cell leukemia. A review of the literature was performed and the potential etiologic link of these two B-cell malignancies is discussed in the light of available information.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Falência Renal Crônica/terapia , Linfoma Difuso de Grandes Células B/terapia , Segunda Neoplasia Primária/terapia , Diálise Renal , Idoso , Anticorpos Monoclonais Murinos , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Humanos , Falência Renal Crônica/complicações , Leucemia de Células Pilosas , Linfoma Difuso de Grandes Células B/patologia , Masculino , Segunda Neoplasia Primária/patologia , Prednisona/administração & dosagem , Indução de Remissão , Rituximab , Vincristina/administração & dosagem
13.
Clin Exp Immunol ; 144(3): 528-33, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16734623

RESUMO

gammadelta T cells account for up to 10% of T lymphocytes in the peripheral blood of healthy donors. They can be activated by cytokines such as interleukin (IL)-2, IL-12 and IL-15, express natural killer (NK) cell markers such as NKG2D and show cytotoxic activity against several tumour cells, including multiple myeloma. Here, we present activated polyclonal gammadelta T cells from healthy donors with an NK T cell-like phenotype expressing the natural cytotoxicity receptor NKp44. Natural cytotoxicity receptors NKp30, NKp44 and NKp46 have been regarded as specific NK receptors; only two gammadelta T cell clones described so far expressed NKp 44. Isolated polyclonal gammadelta T cells cultured for 7 days according to the cytokine-induced killer cell (CIK) protocol with additional IL-15 revealed a surface expression of NKp44 of 8+/-7% (n=22). This could be confirmed by detection of NKp 44 mRNA by reverse transcription-polymerase chain reaction (RT-PCR). gammadelta T cells exhibited a marked cytotoxic activity against myeloma cells, which could be reduced by inhibition of NKp44. To our knowledge, this is the first description of the expression of NKp44 on polyclonal gammadelta T cells.


Assuntos
Citotoxicidade Imunológica , Células Matadoras Naturais/imunologia , Mieloma Múltiplo/patologia , Receptores de Antígenos de Linfócitos T gama-delta/análise , Receptores Imunológicos/metabolismo , Células Cultivadas , Regulação da Expressão Gênica/imunologia , Humanos , Imunofenotipagem , Interleucina-15/imunologia , Interleucina-2/imunologia , Ativação Linfocitária , Mieloma Múltiplo/imunologia , Receptor 2 Desencadeador da Citotoxicidade Natural , RNA Mensageiro/genética , Receptores Imunológicos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Células Tumorais Cultivadas
14.
Endoscopy ; 38(6): 604-9, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16673309

RESUMO

BACKGROUND AND STUDY AIMS: The diagnosis of bile duct cancer is hampered by the low sensitivity of intraductal brush cytology and forceps biopsy. In the present study real-time reverse transcription polymerase chain reaction (RT-PCR) assays for the detection of human aspartyl (asparaginyl) beta-hydroxylase (HAAH) and homeobox B7 (HoxB7) mRNA from intraductal brush cytology specimens were established. Both markers are overexpressed in biliary cancer cell lines and possibly involved in the pathogenesis of bile duct cancer. PATIENTS AND METHODS: RT-PCR assays were validated for detection limit, in-assay variability, and inter-assay variability. Target gene expression was determined in brush cytology specimens from 16 patients with biliary strictures (11 with histologically proven cholangiocarcinomas and five with benign biliary strictures). RESULTS: The assay was quick (about 3 h), highly sensitive (with detection limits between 3 and 106 molecules), and reproducible (maximum in-assay variability 10.3 %, maximum inter-assay variability 11.8 %). The sensitivity of routine brush cytology alone was 36 % (four of 11 cases), with 100 % specificity. A combination with detection of HoxB7 and HAAH mRNA increased the overall diagnostic sensitivity to 82 %. CONCLUSIONS: Detection of these markers using the RT-PCR assays from brush cytology specimens described here may prove to be a useful additional tool for the diagnosis of bile duct carcinoma.


Assuntos
Neoplasias dos Ductos Biliares/genética , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/genética , Oxigenases de Função Mista/genética , RNA Mensageiro/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias dos Ductos Biliares/metabolismo , Neoplasias dos Ductos Biliares/patologia , Linhagem Celular Tumoral , Colangiocarcinoma/metabolismo , Colangiocarcinoma/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Gut ; 55(6): 869-77, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16322112

RESUMO

INTRODUCTION: Impaired activity of natural killer (NK) cells has been proposed as a mechanism contributing to viral persistence in hepatitis C virus (HCV) infection. As the function of NK cells is primarily regulated by NK cell receptors (NKR), we analysed whether decreased NK cell function in hepatitis C may be related to dysregulated NKR expression. PATIENTS AND METHODS: Expression of NK cell was analysed by flow cytometry on lymphocytes from HCV(+) subjects (n = 30), patients who became HCV(-) after antiviral therapy (n = 10), healthy individuals (n = 10), and hepatitis B virus (HBV) infected patients (n = 9). Cytolytic function of lymphocytes was studied in a redirected lysis assay and in a standard 51chromium release cytotoxicity assay, respectively. RESULTS: In patients with chronic hepatitis C, we found a significantly reduced proportion of NKp46 and NKp30 expressing NK cells compared with healthy and HBV infected subjects. Low expression of natural cytotoxicity receptor (NCR) was also confirmed in in vitro activated NK cell populations derived from HCV patients compared with uninfected donors. In contrast, patients who cleared HCV under antiviral therapy showed normal expression of NKp44, NKp30, and NKp46. Reduced NCR expression in chronic hepatitis C was associated with a parallel decrease in NCR mediated target cell killing. Furthermore, we found a significantly increased proportion of NKG2A expressing NK cells and CD8+ T cells in HCV positive patients, resulting in a reduced cytolytic activity against cells incubated with the HLA-E stabilising peptide HCV core35-44. CONCLUSION: The present study indicates that defective expression of NKR represents a novel mechanism contributing to impaired function of NK cells and CD8+ T cells in chronic hepatitis C.


Assuntos
Hepatite C Crônica/imunologia , Células Matadoras Naturais/imunologia , Receptores Imunológicos/sangue , Adulto , Idoso , Antivirais/uso terapêutico , Linfócitos T CD8-Positivos/imunologia , Células Cultivadas , Citotoxicidade Imunológica , Feminino , Hepatite C Crônica/tratamento farmacológico , Humanos , Tolerância Imunológica , Masculino , Glicoproteínas de Membrana/sangue , Pessoa de Meia-Idade , Receptor 1 Desencadeador da Citotoxicidade Natural , Receptor 2 Desencadeador da Citotoxicidade Natural , Receptor 3 Desencadeador da Citotoxicidade Natural
16.
J Viral Hepat ; 13(1): 42-6, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16364081

RESUMO

The C-type lectin DC-SIGNR has been shown to bind hepatitis C virus (HCV). Here, we analysed the tandem-repeat polymorphism of the DC-SIGNR gene with respect to intraindividual HCV replication. In a cross-sectional comparison HCV-infected patients (n = 430) and healthy subjects (n = 100) were genotyped for the DC-SIGNR polymorphism using PCR. The distribution of DC-SIGNR alleles did not differ significantly between the two groups. However, HCV-infected patients with 5-, 6-, and 7-repeat alleles had higher HCV-RNA levels when compared with carriers of 4- and 9-repeat alleles (P < 0.05). Thus, the DC-SIGNR polymorphism might affect HCV loads supporting the concept that DC-SIGNR contributes to HCV replication efficacy.


Assuntos
Moléculas de Adesão Celular/genética , Hepacivirus/crescimento & desenvolvimento , Hepatite C/genética , Lectinas Tipo C/genética , Receptores de Superfície Celular/genética , Adulto , Idoso , Alelos , Estudos Transversais , DNA/química , DNA/genética , Feminino , Genótipo , Hepatite C/virologia , Humanos , Modelos Logísticos , Masculino , Repetições de Microssatélites/genética , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo Genético , Sequências de Repetição em Tandem
17.
Dtsch Med Wochenschr ; 130(40): 2257-60, 2005 Oct 07.
Artigo em Alemão | MEDLINE | ID: mdl-16208599

RESUMO

HISTORY AND CLINICAL FINDINGS: A 61-year-old man with dyspnea and diffuse abdominal pain due to increasing ascites caused by liver cirrhosis of unknown etiology was admitted for consideration of transjugular intrahepatic portosystemic stent-shunting (TIPSS). The patient's medical history included paroxysmal nocturnal hemoglobinuria (PNH), presenting as slight hemolysis diagnosed 24 years previously. One year before the patient underwent radical retropubic prostatectomy for a localized prostate cancer. Shortly after this intervention he developed ascites. INVESTIGATIONS: Color Doppler ultrasonography revealed an abnormal flow in the major hepatic veins. Transjugular liver biopsy indicated hepatic a circulatory disorder. Hepatic venography revealed the so-called "spider web" pattern characteristic for the Budd-Chiari syndrome. The hypercoagulable state due to paroxysmal nocturnal hemoglobinuria was accentuated by manipulation on the prostate during prostatectomy and presumably resulted in a thrombotic obstruction of the hepatic veins. TREATMENT AND CLINICAL COURSE: After exclusion of contraindications a transjugular intrahepatic portosystemic stent shunt (TIPSS) was performed, which led to a decrease of portal pressure. Signs of portal hypertension such as esophageal varices and ascites resolved completely. The patient has been free of complaints for one year. CONCLUSION: We assume that a hypercoagulopathy due to asymptomatic paroxysmal nocturnal hemoglobinuria resulted in Budd-Chiari syndrome when boosted by postoperative release of procoagulation factors in the thrombokinase-rich prostate. TIPSS is a therapeutic option in these patients.


Assuntos
Síndrome de Budd-Chiari/diagnóstico , Hemoglobinúria Paroxística/complicações , Derivação Portossistêmica Transjugular Intra-Hepática , Ascite/etiologia , Biópsia/métodos , Síndrome de Budd-Chiari/etiologia , Síndrome de Budd-Chiari/cirurgia , Varizes Esofágicas e Gástricas/etiologia , Hemoglobinúria Paroxística/cirurgia , Veias Hepáticas/diagnóstico por imagem , Humanos , Hipertensão Portal/etiologia , Fígado/irrigação sanguínea , Fígado/patologia , Cirrose Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Flebografia , Prostatectomia/efeitos adversos , Neoplasias da Próstata/cirurgia , Ultrassonografia Doppler em Cores
18.
J Viral Hepat ; 11(6): 519-26, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15500552

RESUMO

Hepatitis C virus (HCV) infection has been shown to be associated with reduced expression of the CC chemokine receptor (CCR) 5, and reduced responsiveness of lymphocytes to chemokines. However, the mechanism by which HCV alters CCR5 expression remains unclear. Here, we investigated whether altered CCR5 expression in hepatitis C results from interactions of CD81 with the HCV E2 protein. Peripheral blood mononuclear cells (PBMC) from HCV-negative individuals were prepared by Ficoll density gradient separation. PBMC subpopulations (CD4+, CD8+ lymphocytes, CD19+ B cells, natural killer (NK) cells and monocyte-derived dendritic cells) were isolated and stimulated with immobilized HCV E2, and changes in CCR5 expression and CC-chemokine secretion were determined. Migration assays were performed using a 5-microm nitrocellulose filter microchamber system according to the manufacturer's recommendations. Exposure of PBMC to HCV E2 induced a dose-dependent release of regulated on activation normal T-cell-expressed and secreted (RANTES), down-regulation of CCR5 expression and intracellular accumulation of CCR5. This effect was blocked by preincubation of PBMC with anti-CD81. RANTES release following exposure to HCV E2 was mainly attributable to CD8+ cells. After exposure to HCV E2 markedly fewer CD8-positive lymphocytes were attracted by RANTES when compared with CD8+ cells that were studied in the absence of HCV E2. Our results suggest that interaction of HCV E2 with CD81 leads to increased RANTES secretion by CD8+ lymphocytes which induces down-regulation of CCR5 surface via receptor internalization resulting in altered lymphocyte migration.


Assuntos
Antígenos CD/metabolismo , Regulação para Baixo , Hepacivirus/patogenicidade , Receptores CCR5/metabolismo , Proteínas do Envelope Viral/metabolismo , Adulto , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Movimento Celular , Quimiocina CCL5/metabolismo , Feminino , Humanos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Ativação Linfocitária , Masculino , Tetraspanina 28 , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/imunologia
19.
J Endotoxin Res ; 6(3): 257-64, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11052181

RESUMO

Monospecific, affinity-purified polyclonal antibodies reacting with the amino-terminal half of the mouse Toll-like receptor 4 (Tlr4) ectodomain failed to block LPS effects and, to the contrary, were capable of inducing TNF synthesis when applied to mouse macrophages and cross-linked with a secondary antibody. This effect was observed with macrophages derived from C3H/HeN and C57BL/10ScSn mice, but not with macrophages derived from C3H/HeJ or C57BL/10ScCr mice, indicating a specific, Tlr4-dependent effect. Neither primary nor secondary antibody caused any response if administered in the absence of the other reagent, nor was any response observed in cells from mice lacking Tlr4, or bearing the Lps(d) mutation of Tlr4. These findings support several conclusions. Tlr4, the essential transducer of LPS responses, may act independently of LPS itself. LPS needs not be internalized, nor must it bind to a secondary target within the cell in order to exert its effect; rather, the receptor alone is required for initiation of a signal. The data are consistent with the hypothesis that a conformational change in Tlr4 is required for activation via this receptor, and reveal that the amino-terminal half of the Tlr4 ectodomain is a target sufficient for antibody-mediated activation.


Assuntos
Anticorpos/farmacologia , Proteínas de Drosophila , Endotoxinas/antagonistas & inibidores , Glicoproteínas de Membrana/imunologia , Receptores de Superfície Celular/imunologia , Animais , Linhagem Celular , Células Cultivadas , Endotoxinas/farmacologia , Macrófagos Peritoneais , Glicoproteínas de Membrana/biossíntese , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Mimetismo Molecular , Receptores de Superfície Celular/biossíntese , Receptores de Superfície Celular/genética , Proteínas Recombinantes/imunologia , Receptor 4 Toll-Like , Receptores Toll-Like , Fator de Necrose Tumoral alfa/imunologia
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