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1.
Eur Heart J Cardiovasc Pharmacother ; 9(6): 536-545, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37253618

RESUMO

BACKGROUND AND AIMS: The efficacy of statin therapy is hindered by intolerance to the therapy, leading to discontinuation. Variants in SLCO1B1, which encodes the hepatic transporter OATB1B1, influence statin pharmacokinetics, resulting in altered plasma concentrations of the drug and its metabolites. Current pharmacogenetic guidelines require sequencing of the SLCO1B1 gene, which is more expensive and less accessible than genotyping. In this study, we aimed to develop an easy, clinically implementable functional gene risk score (GRS) of common variants in SLCO1B1 to identify patients at risk of statin intolerance. METHODS AND RESULTS: A GRS was developed from four common variants in SLCO1B1. In statin users from Tayside, Scotland, UK, those with a high-risk GRS had increased odds across three phenotypes of statin intolerance [general statin intolerance (GSI): ORGSI 2.42; 95% confidence interval (CI): 1.29-4.31, P = 0.003; statin-related myopathy: ORSRM 2.51; 95% CI: 1.28-4.53, P = 0.004; statin-related suspected rhabdomyolysis: ORSRSR 2.85; 95% CI: 1.03-6.65, P = 0.02]. In contrast, using the Val174Ala genotype alone or the recommended OATP1B1 functional phenotypes produced weaker and less reliable results. A meta-analysis with results from adjudicated cases of statin-induced myopathy in the PREDICTION-ADR Consortium confirmed these findings (ORVal174Ala 1.99; 95% CI: 1.01-3.95, P = 0.048; ORGRS 1.76; 95% CI: 1.16-2.69, P = 0.008). For those requiring high-dose statin therapy, the high-risk GRS was more consistently associated with the time to onset of statin intolerance amongst the three phenotypes compared with Val174Ala (GSI: HRVal174Ala 2.49; 95% CI: 1.09-5.68, P = 0.03; HRGRS 2.44; 95% CI: 1.46-4.08, P < 0.001). Finally, sequence kernel association testing confirmed that rare variants in SLCO1B1 are associated with the risk of intolerance (P = 0.02). CONCLUSION: We provide evidence that a GRS based on four common SLCO1B1 variants provides an easily implemented genetic tool that is more reliable than the current recommended practice in estimating the risk and predicting early-onset statin intolerance.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , Doenças Musculares , Humanos , Genótipo , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Transportador 1 de Ânion Orgânico Específico do Fígado/genética , Doenças Musculares/induzido quimicamente , Doenças Musculares/diagnóstico , Doenças Musculares/genética , Fenótipo , Fatores de Risco
2.
Front Pharmacol ; 14: 1090010, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36998609

RESUMO

Background/Aims: Statin intolerance leads to poor adherence to statin therapy, resulting in a failure to achieve desired cholesterol reduction and adverse outcomes. The LILRB5 Asp247Gly genotype has been identified as being associated with statin intolerance and statin-induced myalgia. We conducted a randomized clinical trial to examine its role in immune response through T regulatory cell aggregation and in achieving cholesterol reduction targets. Methods: A double-blind, cross-over, recruit-by-genotype trial was undertaken. A total of 18 participants who had either the Asp247Asp (T/T) genotype or the Gly247Gly (C/C) genotype were recruited to the study. Participants were randomised to receive placebo or atorvastatin 80 mg daily for 28 days. Following a washout period of 3 weeks, they were then switched to the opposite treatment. Biochemical and immunological measurements as well as interviews were performed prior to and after both treatment periods. Within genotype group comparisons were performed using repeated measures Wilcoxon tests. Two-way repeated measures ANOVA with genotype and treatment as factors were used to compare changes in biochemical parameters between groups during placebo and atorvastatin periods. Results: Individuals with the Asp247Asp genotype had a greater increase in creatine kinase (CK) compared to those with Gly247Gly genotype in response to atorvastatin (p = 0.03). Those with Gly247Gly genotype had a mean non-HDL cholesterol reduction of 2.44 (95% CI:1.59 - 3.29) mmol/L while in Asp247Asp genotype group the mean reduction was 1.28 (95%CI: 0.48 - 2.07) mmol/L. The interaction between the genotype and atorvastatin treatment for total cholesterol (p = 0.007) and non-HDL cholesterol response was significant (p = 0.025). Immunological assessment showed no significant changes in aggregation of T regulatory cells by genotype. Conclusion: The Asp247Gly variant in LILRB5, previously associated with statin intolerance, was associated with differential increases in creatine kinase and total cholesterol and non-HDL cholesterol-lowering response to atorvastatin. Taken together, these results suggest that this variant could have utility in precision cardiovascular therapy.

3.
Front Genet ; 12: 713181, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34659336

RESUMO

Background: Statin intolerance impacts approximately 10% of statin users, with side effects ranging from mild myalgia to extreme intolerance resulting in myopathy and rhabdomyolysis. Statin intolerance results in poor adherence to therapy and can impact statin efficacy. Many genetic variants are associated with statin intolerance. The effect of these variants on statin efficacy has not been systematically explored. Methods: Using longitudinal electronic health records and genetic biobank data from Tayside, Scotland, we examined the effect of seven genetic variants with previously reported associations with simvastatin or atorvastatin intolerance on the outcome of statin response. Statin response was measured by the reduction achieved when comparing pre- and post-statin non-high-density lipoprotein-cholesterol (non-HDL-C). Post-treatment statin response was limited to non-HDL-C measured within 6months of therapy initiation. Univariate and multivariable linear regression models were used to assess the main and adjusted effect of the variants on statin efficacy. Results: Around 9,401 statin users met study inclusion criteria, of whom 8,843 were first prescribed simvastatin or atorvastatin. The average difference in post-treatment compared to pre-treatment non-HDL-cholesterol was 1.45 (±1.04) mmol/L. In adjusted analyses, only two variants, one in the gene ATP-binding cassette transporter B1 (ABCB1; rs1045642), and one in leukocyte immunoglobulin like receptor B5 (LILRB5; rs12975366), were associated with statin efficacy. In ABCB1, homozygous carriers of the C allele at rs1045642 had 0.06mmol/L better absolute reduction in non-HDL-cholesterol than carriers of the T allele (95% CI: 0.01, 0.1). In LILRB5 (rs12975366), carriers of the C allele had 0.04mmol/L better absolute reduction compared to those homozygous for the T allele (95% CI: 0.004, 0.08). When combined into a two-variant risk score, individuals with both the rs1045642-CC genotype and the rs12975366-TC or CC genotype had a 0.11mmol/L greater absolute reduction in non-HDL-cholesterol compared to those with rs1045642-TC or TT genotype and the rs12975366-TT genotype (95% CI: 0.05, 0.16; p<0.001). Conclusion: We report two genetic variants for statin adverse drug reactions (ADRs) that are associated with statin efficacy. While the ABCB1 variant has been shown to have an association with statin pharmacokinetics, no similar evidence for LILRB5 has been reported. These findings highlight the value of genetic testing to deliver precision therapeutics to statin users.

4.
Gastrointest Endosc ; 83(5): 998-1004.e1, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26391735

RESUMO

BACKGROUND AND AIMS: The self-propelled disposable colonoscope (SPDC) with a 360° view is designed to enhance visualization, minimize risks of perforation and infection transmission, and shorten operator training time associated with conventional colonoscopy (CC). We evaluated SPDC efficacy for cecal intubation and safety. METHODS: Prospective patients presenting for colorectal cancer screening underwent SPDC immediately followed by CC. Initial patients necessary for SPDC operators to achieve proficiency comprised the training cohort. Subsequent enrolled patients comprised the study cohort. SPDC colonoscopy was performed up to the cecum, where anatomic landmarks were photographed and mucosal suction marks were placed. During SPDC withdrawal, polyps were recorded and similarly marked. On the second pass (by using CC), any potential mucosal damage and suction marks from the SPDC as well as polyps were recorded. Main endpoints included SPDC cecal intubation rates, confirmed by anatomic landmarks and residual marks seen on subsequent CC, and frequency and severity of adverse events and mucosal damage with SPDC. The secondary endpoint was subjective procedure proficiency, evaluated by the operator based on the training cohort. The tertiary endpoint was documenting pathologies visualized with SPDC. RESULTS: Fifty-six of 58 enrolled subjects completed the study. Proficiency with SPDC was attained after 8 to 10 procedures. Cecal intubation was successful in 98.2% (55/56 subjects; 95% confidence interval [CI], 90.4%-99.9%), including 100% (95% CI, 90.7%-100%) of the study cohort and 94.4% (95% CI, 72.7%-99.9%) of the training cohort. No mucosal damage or adverse events were reported. SPDC detected 87.5% of polyps seen in tandem CC, including all polyps larger than 5 mm. CONCLUSIONS: SPDC was highly successful, simple to use, and safe in achieving complete colonoscopy (cecal intubation). ( CLINICAL TRIAL REGISTRATION NUMBER: 0692-12-TLV.).


Assuntos
Pólipos do Colo/diagnóstico por imagem , Colonoscópios , Colonoscopia/instrumentação , Equipamentos Descartáveis , Adulto , Idoso , Pontos de Referência Anatômicos , Ceco , Competência Clínica , Colonoscópios/efeitos adversos , Colonoscopia/efeitos adversos , Feminino , Humanos , Mucosa Intestinal/lesões , Intubação Gastrointestinal , Curva de Aprendizado , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
5.
Endosc Int Open ; 3(6): E642-5, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26716128

RESUMO

BACKGROUND AND STUDY AIMS: The Aer-O-Scope™ Colonoscope System (AOS) combines panoramic 360° view with standard forward view. We assessed the AOS's ability to identify lesions implanted in live swine, compared to conventional colonoscopy (CC). PATIENTS AND METHODS: Twelve swine colons were surgically ligated and beads sewn within. Five procedures (3 AOS and 2 CC) were performed on each swine and findings reported. Physicians were blinded to number, size, and color of beads. The sequence of procedures and physicians was randomized. Pigs, physicians, and colonoscopes were randomly alternated between examination rooms, maintaining physician blindness. Two independent blinded physicians interpreted procedure videos offline. RESULTS: A total of 259 /273 (94.9 %) of lesions were visualized by AOS compared to 158 /182 with CC (86.8 %) (P = 0.002). Miss rates of lesions ≥ 6 mm were 2.6 % and 10.5 %, respectively (P = 0.022), and 6.9 % and 15.1 %, respectively, for lesions < 6 mm (P = 0.031). Mean agreement between AOS and CC for lesion detection was 88.3 %. The benefit of AOS was maintained in offline video review. CONCLUSIONS: AOS, featuring panoramic 360° view, demonstrated high detection rates for simulated colonic lesions in a live swine model.

7.
Endoscopy ; 47(3): 238-44, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25704662

RESUMO

BACKGROUND AND STUDY AIMS: Although colonoscopy is the "gold standard" for colorectal cancer screening, a significant number of adenomas are still missed during standard colonoscopy, often because they are hidden behind colonic folds and flexures. The aim of this study was to assess the ability of a novel balloon colonoscope (G-EYE endoscope; Smart Medical Systems, Ra'anana, Israel) to increase adenoma detection and reduce the miss rate compared with standard colonoscopy. PATIENTS AND METHODS: This was a multicenter, randomized, prospective, controlled study in patients (age ≥ 40 years) undergoing colonoscopy for screening or diagnostic work-up (including surveillance). Patients underwent same-day, back-to-back tandem colonoscopy. Patients in Group A underwent standard colonoscopy followed by balloon colonoscopy, and patients in Group B underwent balloon colonoscopy followed by the standard technique. The adenoma detection and miss rates were compared between the two colonoscopy procedures. RESULTS: A total of 126 patients were enrolled and randomized into Group A (n = 60) or Group B (n = 66). The adenoma miss rate of balloon colonoscopy was significantly lower than that of standard colonoscopy (7.5 % vs. 44.7 %; P = 0.0002). The detection of additional adenomas by balloon colonoscopy was significant (81.0 %; P = 0.0002), in particular, the relative amount of adenomas detected in the ascending colon by balloon colonoscopy was 41 % versus 14 % for standard colonoscopy. CONCLUSIONS: A novel balloon colonoscopy technique detected significantly more adenomas than standard colonoscopy, and missed fewer adenomas. Balloon colonoscopy has the potential to increase the effectiveness of colorectal cancer screening and surveillance colonoscopy.


Assuntos
Adenoma/diagnóstico , Neoplasias do Colo/diagnóstico , Colonoscópios , Colonoscopia/instrumentação , Adenoma/patologia , Idoso , Colo Ascendente , Neoplasias do Colo/patologia , Colonoscopia/métodos , Detecção Precoce de Câncer , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Método Simples-Cego
8.
Lancet Oncol ; 15(3): 353-60, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24560453

RESUMO

BACKGROUND: Although colonoscopy is the accepted standard for detection of colorectal adenomas and cancers, many adenomas and some cancers are missed. To avoid interval colorectal cancer, the adenoma miss rate of colonoscopy needs to be reduced by improvement of colonoscopy technique and imaging capability. We aimed to compare the adenoma miss rates of full-spectrum endoscopy colonoscopy with those of standard forward-viewing colonoscopy. METHODS: We did an international, multicentre, randomised trial at three sites in Israel, one site in the Netherlands, and two sites in the USA between Feb 1, 2012, and March 31, 2013. Patients aged 18-70 years referred for colorectal cancer screening, polyp surveillance, or diagnostic assessment underwent same-day, back-to-back tandem colonoscopy with standard forward-viewing colonoscope and the full-spectrum endoscopy colonoscope. The patients were randomly assigned (1:1), via computer-generated randomisation with block size of 20, to which procedure was done first. The endoscopist was masked to group allocation until immediately before the start of colonoscopy examinations; patients were not masked. The primary endpoint was adenoma miss rates. We did per-protocol analyses. This trial is registered with ClinicalTrials.gov, number NCT01549535. FINDINGS: 197 participants were enrolled. 185 participants were included in the per-protocol analyses: 88 (48%) were randomly assigned to receive standard forward-viewing colonoscopy first, and 97 (52%) to receive full-spectrum endoscopy colonoscopy first. By per-lesion analysis, the adenoma miss rate was significantly lower in patients in the full-spectrum endoscopy group than in those in the standard forward-viewing procedure group: five (7%) of 67 vs 20 (41%) of 49 adenomas were missed (p<0·0001). Standard forward-viewing colonoscopy missed 20 adenomas in 15 patients; of those, three (15%) were advanced adenomas. Full-spectrum endoscopy missed five adenomas in five patients in whom an adenoma had already been detected with first-pass standard forward-viewing colonoscopy; none of these missed adenomas were advanced. One patient was admitted to hospital for colitis detected at colonoscopy, whereas five minor adverse events were reported including vomiting, diarrhoea, cystitis, gastroenteritis, and bleeding. INTERPRETATION: Full-spectrum endoscopy represents a technology advancement for colonoscopy and could improve the efficacy of colorectal cancer screening and surveillance. FUNDING: EndoChoice.


Assuntos
Adenoma/diagnóstico , Colonoscopia/métodos , Neoplasias Colorretais/diagnóstico , Adolescente , Adulto , Idoso , Humanos , Pessoa de Meia-Idade
9.
Tissue Eng Part C Methods ; 14(4): 341-51, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18844603

RESUMO

Human hepatic stem cells (hHpSCs), identifiable by a unique antigenic profile, have been isolated from human livers and established ex vivo under expansion conditions permissive for self-replication. The conditions consist of a substratum of type III collagen, ideally on Transwell inserts, and Kubota's medium, a serum-free medium developed for hepatic progenitors. Under these conditions the cells demonstrated a doubling time of approximately 24 h, generating at least a 16-fold increase in cell number within 7-10 days; were stable at confluence for up to 2 weeks; could be passaged, if on type III collagen, to initiate colonies that went through log-phase growth and saturation density kinetics; and expressed telomerase, indicative of regenerative capacity. The hHpSC colonies remained morphologically and phenotypically stable throughout expressing epithelial cell adhesion molecule, neural cell adhesion molecule, albumin, cytokeratins 8, 18, and 19, but not alpha-fetoprotein, or intercellular adhesion molecule-1 (ICAM-1). Those maintained under self-replication conditions for more than a month were transplanted and found to engraft in the livers of SCID/nod mice yielding human liver tissue expressing adult liver-specific proteins. The conditions for self-replication should offer ideal culture conditions for generating large numbers of hHpSCs for use in commercial and clinical programs.


Assuntos
Técnicas de Cultura de Células/métodos , Proliferação de Células , Células-Tronco Hematopoéticas/citologia , Fígado/citologia , Engenharia Tecidual/métodos , Albuminas/metabolismo , Adesão Celular , Colágeno/química , Células HeLa , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Queratinas/metabolismo , Fígado/metabolismo , Microscopia de Fluorescência , Microscopia de Contraste de Fase , Telomerase/metabolismo
10.
J Exp Med ; 204(8): 1973-87, 2007 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-17664288

RESUMO

Human hepatic stem cells (hHpSCs), which are pluripotent precursors of hepatoblasts and thence of hepatocytic and biliary epithelia, are located in ductal plates in fetal livers and in Canals of Hering in adult livers. They can be isolated by immunoselection for epithelial cell adhesion molecule-positive (EpCAM+) cells, and they constitute approximately 0.5-2.5% of liver parenchyma of all donor ages. The self-renewal capacity of hHpSCs is indicated by phenotypic stability after expansion for >150 population doublings in a serum-free, defined medium and with a doubling time of approximately 36 h. Survival and proliferation of hHpSCs require paracrine signaling by hepatic stellate cells and/or angioblasts that coisolate with them. The hHpSCs are approximately 9 microm in diameter, express cytokeratins 8, 18, and 19, CD133/1, telomerase, CD44H, claudin 3, and albumin (weakly). They are negative for alpha-fetoprotein (AFP), intercellular adhesion molecule (ICAM) 1, and for markers of adult liver cells (cytochrome P450s), hemopoietic cells (CD45), and mesenchymal cells (vascular endothelial growth factor receptor and desmin). If transferred to STO feeders, hHpSCs give rise to hepatoblasts, which are recognizable by cordlike colony morphology and up-regulation of AFP, P4503A7, and ICAM1. Transplantation of freshly isolated EpCAM+ cells or of hHpSCs expanded in culture into NOD/SCID mice results in mature liver tissue expressing human-specific proteins. The hHpSCs are candidates for liver cell therapies.


Assuntos
Técnicas de Cultura de Células/métodos , Fígado/citologia , Fígado/embriologia , Células-Tronco/citologia , Adesão Celular , Membrana Celular/metabolismo , Meios de Cultura Livres de Soro/metabolismo , Células Epiteliais/citologia , Células-Tronco Hematopoéticas/metabolismo , Hepatócitos/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Antígenos Comuns de Leucócito/biossíntese , Fígado/metabolismo , Mesoderma/metabolismo , Transdução de Sinais , alfa-Fetoproteínas/metabolismo
11.
Am J Physiol Gastrointest Liver Physiol ; 292(2): G628-38, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17038628

RESUMO

While CD8 subsets activate hepatic fibrosis, natural killer (NK) cells exhibit antifibrotic activity. Glatiramer acetate (GA) is an immune modulator for multiple sclerosis. We assessed the potential impact of GA on mouse hepatic fibrogenesis. Hepatic fibrosis was induced in C57BL/6 mice by intraperitoneal administration of carbon tetrachloride (CCl(4)) for 6 wk. During the last 2 wk, animals were also treated with either GA (200 mu/day ip) or medium and compared with naive and fibrotic mice (8 animals/group). GA markedly attenuated fibrosis without altering reactive oxygen species production. By morphometric measurement of Sirius red-stained tissue sections, the relative fibrosis area decreased from 5.28 +/- 0.32% (mean +/- SE) in the untreated CCl(4) group to 2.01 +/- 0.28% in CCl(4)+GA-treated animals, compared with 0.38 +/- 0.07% in naive mice. alpha-Smooth muscle actin immunoblotting and mRNA expression revealed a similar pattern. Serum aminotransferase and Ishak-Knodell necroinflammatory score were markedly elevated, to the same extent, in both CCl(4)-treated groups. Fibrosis induction was associated with significant increase in CD8 subsets and decrease in CD4 T cells. After GA treatment, however, NK content, CD4(+)CD25(+)FoxP3(+) cells, hepatic expression of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), and apoptosis of hepatic stellate cells were all increased. Serum interleukin (IL)-10 levels markedly rose, whereas IL-4 fell. In vitro activation of human hepatic stellate cells cocultured with hepatitis C virus-derived peripheral blood lymphocytes decreased when lymphocytes were preincubated with GA before coculture. In an animal model of hepatic fibrosis, GA has an antifibrotic effect associated with decreased CD8 cells and reduced serum IL-4 levels and increased NK cells, CD4(+)CD25(+)FoxP3(+) cells, TRAIL, and elevated serum IL-10 levels.


Assuntos
Fatores Imunológicos/uso terapêutico , Cirrose Hepática Experimental/tratamento farmacológico , Peptídeos/uso terapêutico , Actinas/genética , Actinas/metabolismo , Alanina Transaminase/sangue , Animais , Apoptose/efeitos dos fármacos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Tetracloreto de Carbono/toxicidade , Células Cultivadas , Citocromo P-450 CYP2E1/metabolismo , Expressão Gênica/efeitos dos fármacos , Acetato de Glatiramer , Glutamil Aminopeptidase/sangue , Humanos , Fatores Imunológicos/farmacologia , Interferon gama/sangue , Interleucina-10/sangue , Interleucina-4/sangue , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática Experimental/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Peptídeos/farmacologia , Baço/efeitos dos fármacos , Baço/imunologia , Baço/patologia , Ligante Indutor de Apoptose Relacionado a TNF/genética
12.
J Hepatol ; 45(1): 60-71, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16515819

RESUMO

BACKGROUND/AIMS: We have investigated the role of natural killer (NK) cells in hepatic fibrogenesis. Mouse NK cells express both inhibitory/activating-killing-immunoglobulin-related-receptors (iKIR/aKIR) specific for Class-I-molecules. METHODS: Hepatic fibrosis induced by carbon-tetrachloride (CCl4) was compared between wild-type (WT) male-BALBc; combined-immunodeficiency (SCID, lacking B/T-cells); and SCID-BEIGE-mice (lacking B/T/NK cells), and naive mice. RESULTS: Hepatic fibrosis significantly increased in all CCl4-treated groups. SCID-BEIGE mice had more fibrosis than SCID-mice (P<0.0001) as assessed by morphometry of sirius-red stained tissue sections. Following fibrosis, hepatic NK cells significantly decreased, the aKIR:iKIR-ratio significantly increased while Class-I expression on HSC decreased (P<0.001). Both freshly isolated and in situ HSC displayed a significant increase in cellular apoptosis following fibrosis induction. Confocal microscopy demonstrated the direct adhesion of NK cells to HSC in mouse liver sections and in vitro human NK/HSC co-culture. In human HSC there was decreased Class-I expression and increased apoptosis as well, which was further increased following blocking of either HSC-related Class-I or NK-related killer inhibitory receptors. Apoptosis was inhibited by pre-incubation of NK cells with the granzyme inhibitor 3,4-dichloroisocoumarin. CONCLUSIONS: During liver injury, NK cells have an anti-fibrotic activity at least in part through stimulation of HSC killing.


Assuntos
Hepatócitos/imunologia , Células Matadoras Naturais/imunologia , Cirrose Hepática/imunologia , Actinas/análise , Animais , Sobrevivência Celular , Modelos Animais de Doenças , Hepatócitos/patologia , Humanos , Cirrose Hepática/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos SCID , Músculo Liso/imunologia , Músculo Liso/patologia
13.
Am J Physiol Gastrointest Liver Physiol ; 290(5): G859-70, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16322088

RESUMO

Hedgehog signaling through its receptor, Patched, activates transcription of genes, including Patched, that regulate the fate of various progenitors. Although Hedgehog signaling is required for endodermal commitment and hepatogenesis, the possibility that it regulates liver turnover in adults had not been considered because mature liver epithelial cells lack Hedgehog signaling. Herein, we show that this pathway is essential throughout life for maintaining hepatic progenitors. Patched-expressing cells have been identified among endodermally lineage-restricted, murine embryonic stem cells as well as in livers of fetal and adult Ptc-lacZ mice. An adult-derived, murine hepatic progenitor cell line expresses Patched, and Hedgehog-responsive cells exist in stem cell compartments of fetal and adult human livers. In both species, manipulation of Hedgehog activity influences hepatic progenitor cell survival. Therefore, Hedgehog signaling is conserved in hepatic progenitors from fetal development through adulthood and may be a new therapeutic target in patients with liver damage.


Assuntos
Fígado/citologia , Receptores de Superfície Celular/metabolismo , Transdução de Sinais , Células-Tronco/metabolismo , Transativadores/metabolismo , Animais , Indução Embrionária , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Hedgehog , Hepatócitos/metabolismo , Humanos , Fígado/embriologia , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Receptores Patched , Receptor Patched-1 , Receptores de Superfície Celular/fisiologia , Células-Tronco/fisiologia , Transativadores/fisiologia
14.
Liver Int ; 24(4): 295-307, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15287852

RESUMO

BACKGROUND: Anti-viral immunity can be modulated via oral feeding of viral proteins. Hepatitis B and C viral (HBV, HCV)-associated hepatocellular injury is mediated by a defective host anti-viral immune response. AIMS: To determine the effect of oral administration of a mixture of liver-extracted proteins with HBV/HCV proteins, on viral load, liver injury, and the anti-viral T-cell response of chronic HBV/HCV patients. METHODS: Fourteen patients with chronic HBV and 15 patients with chronic HCV were treated orally with hepatocyte-extracted proteins and HBV or HCV viral proteins for 24 weeks, and followed for an additional 26 weeks. Patients were monitored for HBV-DNA or HCV-RNA levels, liver enzymes and liver histology. Viral-directed T-cell immunity was assessed by IFNgamma and IL10 ELISPOT, viral-specific T-cell proliferation, cytotoxicity, and cytokines assays, and followed for peripheral natural killer T-cell (NKT) number. RESULTS: In both chronic HBV and HCV patients, oral administration of a mixture of selected liver-extracted proteins and viral proteins induced a favorable increase in viral-specific T-cell proliferation, and IFNgamma-secreting clones, along with a significant decrease in the anti-viral IL10-secreting T-cell clones. However, the effects of modulation of the anti-viral immunity differed between the HBV and HCV patients. In both groups, no major adverse events were noted. In chronic HBV patients, a significant decrease in viral load was observed in 5/14 (35.7%) of patients. HB surface antigen/HB nucleocapsid antigen scores on liver biopsy improved in 46.1% and 50%, respectively, and the histological necroinflammatory score improved in 4/13 (30.7%). Forty percent of the patients with elevated liver enzymes showed a favorable biochemical response. In contrast, an improvement in the histological necroinflammatory score was observed in only 2/12 (17%) of the chronic HCV patients. No significant decrease in HCV RNA was noted in any of these patients. CONCLUSIONS: Immune regulation of the anti-HBV/HCV immune response via oral administration of a mixture of liver-extracted and viral proteins significantly altered the viral-specific immunity. This effect was associated with clinical and virological improvements in chronic HBV patients.


Assuntos
Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/imunologia , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/imunologia , Proteínas Virais/administração & dosagem , Administração Oral , Adolescente , Adulto , Divisão Celular/imunologia , Radioisótopos de Cromo , Feminino , Antígenos E da Hepatite B/metabolismo , Humanos , Interferon gama/metabolismo , Interleucina-10/metabolismo , Fígado/enzimologia , Fígado/imunologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Resultado do Tratamento , Carga Viral , Proteínas Virais/efeitos adversos
15.
Am J Gastroenterol ; 98(11): 2505-15, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14638356

RESUMO

OBJECTIVES: Hepatitis B virus (HBV) is a noncytopathic virus, and hepatocellular injury is mediated by a defective host antiviral immune response. We have previously shown that antiviral immunity can be modulated through oral feeding of viral proteins. The aims of this study were to determine the safety and efficacy of treatment of patients with chronic HBV by means of p.o. administration of HBV envelope proteins. METHODS: A total of 42 chronic HBV patients were treated p.o. with HBV envelope proteins (HBsAg+preS1+preS2), three times/wk for 20-30 wk, and followed for an additional 20 wk. Patients were monitored for HBV-DNA levels, liver enzymes, and liver histology. HBV-directed T cell immune modulation was assessed in vitro by HBV specific T cell-proliferation, cytotoxicity, IFN gamma, and IL10 ELISPOT assays, and reverse transcription-polymerase chain reaction cytokines assay. RESULTS: Favorable response in one of the primary endpoints was achieved in 28/42 patients (66.6%) by means of p.o. immune regulation. A significant decrease in viral load was observed in 15 patients (35.7%). HBsAg/HBcAg biopsy scores improved in 41% and 57.1% of patients, respectively. Histological improvement in liver necroinflammatory score was noted in 12/40 patients (30%). In all, 80% showed biochemical response. Five of 19 HBeAg positive patients (26.3%) became negative for HBeAg. A favorable augmentation in anti-HBV specific T cell response, with increased HbsAg specific T cell proliferation (78%), cytotoxicity (75%), and IFN gamma positive T cell clones (62.9%) was noted. In addition, a decrease in the IL10 gamma positive T cell clones was achieved (48.1%). Natural killer T (NKT) lymphocytes increased significantly in all treated patients. CONCLUSIONS: Immune regulation of the anti-HBV immune response via p.o. administration of HBV envelope proteins alleviated the immune-mediated liver injury while augmenting the effective antiviral immunity.


Assuntos
Antígenos de Superfície da Hepatite B/uso terapêutico , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/terapia , Tolerância Imunológica/fisiologia , Proteínas do Core Viral/efeitos dos fármacos , Administração Oral , Adolescente , Adulto , Idoso , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Hepatite B Crônica/diagnóstico , Humanos , Imunoterapia/métodos , Masculino , Pessoa de Meia-Idade , Probabilidade , Estudos Prospectivos , Medição de Risco , Estatísticas não Paramétricas , Resultado do Tratamento
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