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Histamine intolerance is a condition characterized by the accumulation of histamine to a point that exceeds the body's capacity to eliminate it. Researchers have attributed several reasons to this condition, such as genetic factors, alcohol, and dietary deficiencies, among other elements. Symptoms of histamine intolerance have been found to extend beyond the gastrointestinal tract and to the whole body, with these symptoms being sporadic and non-specific. This review will explore various aspects related to histamine intolerance, such as its causes, symptoms, diagnosis, and information related to management.
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Intolerancia Alimentaria , Histamina , Humanos , Histamina/metabolismo , Intolerancia Alimentaria/diagnóstico , Hipersensibilidad a los Alimentos/diagnósticoRESUMEN
BACKGROUND: The NLRP3 inflammasome drives release of pro-inflammatory cytokines including interleukin (IL)-1ß and IL-18 and is a potential target for ulcerative colitis (UC). Selnoflast (RO7486967) is an orally active, potent, selective and reversible small molecule NLRP3 inhibitor. We conducted a randomized, placebo-controlled Phase 1b study to assess the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of selnoflast. METHODS: Nineteen adults with previous diagnosis of UC and current active moderate to severe disease were randomized 2:1 to selnoflast or placebo for 7 days. A dose of 450 mg QD (once daily) was selected to achieve 90% IL-1ß inhibition in plasma and colon tissue. Consecutive blood, sigmoid colon biopsies and stool samples were analyzed for a variety of PD markers. Safety and PK were also evaluated. RESULTS: Selnoflast was well-tolerated. Plasma concentrations increased rapidly after oral administration, reaching Tmax 1 h post-dose. Mean plasma concentrations stayed above the IL-1ß IC90 level throughout the dosing interval (mean Ctrough on Day 1 and Day 5: 2.55 µg/mL and 2.66 µg/mL, respectively). At steady state, post-dose selnoflast concentrations in sigmoid colon (5-20 µg/g) were above the IC90 . Production of IL-1ß was reduced in whole blood following ex vivo stimulation with lipopolysaccharide (LPS) (in the selnoflast arm). No changes were observed in plasma IL-18 levels. There were no meaningful differences in the expression of an IL-1-related gene signature in sigmoid colon tissue, and no differences in the expression of stool biomarkers. CONCLUSIONS: Selnoflast was safe and well-tolerated. Selnoflast 450 mg QD achieved plasma and tissue exposure predicted to maintain IL-1ß IC90 over the dosing interval. However, PD biomarker results showed no robust differences between treatment arms, suggesting no major therapeutic effects are to be expected in UC. The limitations of this study are its small sample size and indirect assessment of the effect on IL-1ß in tissue. TRIAL REGISTRATION: ISRCTN16847938.
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Colitis Ulcerosa , Adulto , Humanos , Colitis Ulcerosa/tratamiento farmacológico , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Interleucina-18/uso terapéutico , Inflamasomas/metabolismo , Citocinas/metabolismo , BiomarcadoresRESUMEN
INTRODUCTION: The human intestinal tract reacts to extensive resection with spontaneous intestinal adaptation. We analyzed whether gene expression analyses or intestinal permeability (IP) testing could provide biomarkers to describe regulation mechanisms in the intestinal barrier in short bowel syndrome (SBS) patients during adaptive response or treatment with the glucagon-like peptide-2 analog teduglutide. METHODS: Relevant regions of the GLP-2 receptor gene were sequenced. Gene expression analyses and immunohistochemistry were performed from mucosal biopsies. IP was assessed using a carbohydrate oral ingestion test. RESULTS: The study includes 59 SBS patients and 19 controls. Increases in gene expression with teduglutide were received for sucrase-isomaltase, sodium/glucose cotransporter 1, and calcium/calmodulin serine protein kinase. Mannitol recovery was decreased in SBS but elevated with teduglutide (Δ 40%), showed a positive correlation with remnant small bowel and an inverse correlation with parenteral support. CONCLUSIONS: Biomarkers predicting clinical and functional features in human SBS are very limited. Altered specific gene expression was shown for genes involved in nutrient transport but not for genes controlling tight junctions. However, mannitol recovery proved useful in describing the absorptive capacity of the gut during adaptation and treatment with teduglutide.
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Síndrome del Intestino Corto , Humanos , Síndrome del Intestino Corto/terapia , Intestino Delgado/patología , Péptido 2 Similar al Glucagón , Biomarcadores , Manitol , Fármacos Gastrointestinales/uso terapéuticoRESUMEN
OBJECTIVES: C-C-chemokine receptors (CCRs) are expressed on a variety of immune cells and play an important role in many immune processes, particularly leukocyte migration. Comprehensive preclinical research demonstrated CCR2/CCR5-dependent pathways as pivotal for the pathophysiology of severe COVID-19. Here we report human data on use of a chemokine receptor inhibitor in patients with COVID-19. METHODS: Interim results of a 2:1 randomised, placebo-controlled, investigator-initiated trial on the CCR2/CCR5-inhibitor Cenicriviroc (CVC) 150 mg BID orally for 28 d in hospitalised patients with moderate to severe COVID-19 are reported. The primary endpoint is the subject's responder status defined by achieving grade 1 or 2 on the 7-point ordinal scale of clinical improvement on day 15. RESULTS: Of the 30 patients randomised, 18 were assigned to receive CVC and 12 to placebo. Efficient CCR2- and CCR5 inhibition was demonstrated through CCL2 and CCL4 elevation in CVC-treated patients (485% and 80% increase on day 3 compared to the baseline, respectively). In the modified intention-to-treat population, 82.4% of patients (14/17) in the CVC group met the primary endpoint, as did 91.7% (11/12) in the placebo group (OR = 0.5, 95% CI = 0.04-3.41). One patient treated with CVC died of progressive acute respiratory distress syndrome, and the remaining had a favourable outcome. Overall, treatment with CVC was well tolerated, with most adverse events being grade I or II and resolving spontaneously. CONCLUSIONS: Our interim analysis provides proof-of-concept data on CVC for COVID-19 patients as an intervention to inhibit CCR2/CCR5. Further studies are warranted to assess its clinical efficacy.
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COVID-19 , Humanos , SARS-CoV-2 , Imidazoles , SulfóxidosRESUMEN
The functional gastrointestinal disorders (FGIDs) have a high prevalence and are associated with high healthcare costs. The diagnosis of these diseases could be difficult and require func-tional tests such as high-resolution manometry (HRM) of the esophagus, anorectal manometry and H2-Breathtests. Due to the COVID-19 Pandemic and the fear of infections there was a marked reduction in the number of performed exams in the last months - nevertheless some exams are necessary, in order to exclude or to diagnose important and dangerous diseases like Achalasia. Goal of this article is to present some new and relevant developments in the field. The HRM of the esophagus is the diagnostic standard for Achalasia, a rare clinical condi-tion associated to dysphagia - new European guidelines suggests a safe strategy in perform-ing the pneumatic dilatation.The intestinal methanogen overgrowth (IMO) is a clinical condition caused by a high production of methane in the small intestine due to overgrowth of Methanobrevibacter smithii, this condition could be in some patients associated with irritable bowel syndrome.
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COVID-19/complicaciones , Enfermedades Gastrointestinales/diagnóstico , Archaea/metabolismo , Pruebas Respiratorias , Acalasia del Esófago/diagnóstico , Esófago/fisiopatología , Enfermedades Gastrointestinales/economía , Enfermedades Gastrointestinales/epidemiología , Humanos , Intestino Delgado/microbiología , Manometría , Metano/biosíntesis , Guías de Práctica Clínica como Asunto , Recto/fisiopatologíaRESUMEN
The glucagon-like peptide-2 (GLP-2) analogue teduglutide is a medical treatment option for patients with short-bowel syndrome-associated chronic intestinal failure. Because studies in mice have shown that GLP-2 analogues may promote the growth of colonic neoplasms, surveillance colonoscopies before and during teduglutide therapy were recommended. The occurrence of small-intestinal neoplasms has not been reported so far, except for a recent report about de novo development of hamartomatous duodenal polyps. We report a case of de novo development of small-intestinal premalignant adenomatous polyps in both bulbar duodenum and distal jejunum in a patient treated with teduglutide for 41 months. Therefore, additional endoscopic surveillance of the upper gastrointestinal tract may be advised during teduglutide therapy for early detection and removal of potential small-bowel adenomas.
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Adenoma , Síndrome del Intestino Corto , Adenoma/complicaciones , Adenoma/tratamiento farmacológico , Fármacos Gastrointestinales/uso terapéutico , Humanos , Yeyuno , Péptidos , Síndrome del Intestino Corto/complicaciones , Síndrome del Intestino Corto/tratamiento farmacológicoRESUMEN
BACKGROUND & AIMS: The pathogenesis of primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) remains unclear. The aim of this study was to reveal certain single nucleotide polymorphisms (SNP) in genes for regulatory proteins in the immunologic pathway possibly going along with susceptibility of attaining PBC or PSC. METHODS: 126 patients with either PBC or PSC with clinical and laboratory data were enrolled in the study. SNPs in three genes (CTLA-4, ICOS, and FOX-P3) which are suspected to play a key role in the autoimmune pathway were analyzed to determine allele variants. Gene expression was measured by RealTime PCR using mRNA. RESULTS: Patients with cirrhosis had a lower number of CTLA-4 copies than patients without cirrhosis (p = 0.04). Accordingly, patients with lower CTLA-4 copies had a poorer recovery of gamma-glutamyltransferase (GGT) in course of their disease (-69.8 U/l vs. -176.1 U/l p = 0.04). Two SNP allele variants (CTLA4 rs733618 and FOXP3 rs2280883) associated with low CTLA-4 expression could be determined. Patients having both variants showed worsening of GGT (-61.7 U/l vs. -132.6 U/l, p = 0.04) and a trend towards a more progressive disease in terms of cirrhosis. (24% vs. 13% p = ns). CONCLUSIONS: Low expression of CTLA-4 is associated with a more advanced disease in patients with PBC and PSC. Furthermore, we identified two SNP allele variants (CTLA4-SNP rs733618 and FOXP3-SNP rs2280883) associated with a lower CTLA-4 expression and possibly a more severe course of the diseases. Taken together, these results provide further evidence for the involvement of the immune system in the pathogenesis of these two cholestatic liver diseases. Lay summary: Primary biliary cholangitis and primary sclerosing cholangitis are chronic diseases of the bile ducts. Their cause remains widely unclear, but evidence suggests the immune system plays a central role. This study shows that gene alterations connected to the immune system might play a role in the course of the disease.
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Natural killer (NK) cells are non-T, non-B lymphocytes are part of the innate immune system and function without prior activation. The human NK cell surface determinant, CD94, plays a critical role in regulation of NK cell activity as a heterodimer with NKG2 subclasses. Canine NK cells are not as well defined as the human and murine equivalents, due in part to the paucity of reagents specific to cell surface markers. Canines possess NK/NKT cells that have similar morphological characteristics to those found in humans, yet little is known about their functional characteristics nor of cell surface expression of CD94. Here, we describe the development and function of a monoclonal antibody (mAb) to canine (ca) CD94. Freshly isolated canine CD94+ cells were CD3+/-, CD8+/-, CD4-, CD21-, CD5low, NKp46+, and were cytotoxic against a canine target cell line. Anti-caCD94 mAb proved useful in enriching NK/NKT cells from PBMC for expansion on CTAC feeder cells in the presence of IL-2 and IL-15. The cultured cells were highly cytolytic with co-expression of NKp46 and reduced expression of CD3. Transmission electron microscopy revealed expanded CD94+ lymphocytes were morphologically large granular lymphocytes with large electron dense granules. Anti-caCD94 (mAb) can serve to enrich NK/NKT cells from dog peripheral blood for ex vivo expansion for HCT and is a potentially valuable reagent for studying NK/NKT regulation in the dog.
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Anticuerpos Monoclonales/inmunología , Perros/inmunología , Subfamília D de Receptores Similares a Lectina de las Células NK/inmunología , Animales , Especificidad de Anticuerpos/inmunología , Clonación Molecular , Femenino , Citometría de Flujo/veterinaria , Células Asesinas Naturales/inmunología , Masculino , Ratones/inmunología , Células T Asesinas Naturales/inmunología , Reacción en Cadena de la Polimerasa/veterinariaRESUMEN
OBJECTIVES: Spleen stiffness (SS) correlates with liver stiffness (LS) and hepatic venous pressure gradient. The latter is currently the most accurate predictor of hepatic decompensation. Our study aims to check whether SS has a similar predictive capability, while being an easy-to-perform noninvasive test in a real-life patient cohort. METHODS: Concomitantly, 210 successive patients were examined and received liver and SS measurements and a standard laboratory. Patients were observed for 1 year in terms of clinical signs of decompensation. RESULTS: One hundred fifty-nine of the initial 210 patients had a valid LS and SS measurement and were evaluable for clinical follow-up. Twelve patients developed a hepatic decompensation; with a SS >39 kPa (P=0.0005). Especially in a group with elevated LS, patients with a high risk of decompensation could be identified using SS. Patients with comparable LS who suffered from acute liver damage had significantly lower SS than respective patients with chronic liver damage (30.97 vs. 46.03 kPa; P=0.04). Acute liver failure was associated with elevated LS (16.47 kPa) but not with elevated SS (30.97 kPa). CONCLUSIONS: The risk of a hepatic decompensation can easily be assessed using SS measurement. Therefore SS measurement might be a powerful screening tool identifying patients who need closer monitoring. Moreover, SS is able to differentiate between acute and chronic or acute on chronic liver damage.
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Diagnóstico por Imagen de Elasticidad , Hígado/fisiopatología , Bazo/fisiopatología , Presión Venosa/fisiología , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad Crónica , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
BACKGROUND: Clostridium difficile associated colitis is a frequent cause of nosocomial diarrhea at the intensive care unit (ICU) and is associated with poor prognosis in critically ill patients. Few studies have evaluated the efficacy of treatment options or adherence to guideline recommendations of Clostridium difficile infections at the ICU. METHODS: Therefore, on behalf of the Gastroenterology Intensive Care Medicine working group of the DGVS, we have conducted an online-based survey among leading intensivists in Germany. RESULTS: Out of the 351 invited, 85 (24.2â%), primarily leading executive physicians at primary to tertiary care hospitals, completed the survey. They reported standardized diagnostic algorithms of 79.3â%, in line with current guideline recommendations (i.âe., toxin testing in stool, possibly GDH screening, and endoscopy). First-line therapy of Clostridium difficile infections at the ICU was reported to be oral vancomycin in 48.3â% and oral metronidazole in 34.5â%. The success of first-line therapy was estimated at 67â% for clinical cure, 15â% persisting colitis, 5â% sepsis or megacolon, 10â% recurrence, and 3â% death. Hospitals of primary/secondary care more often used metronidazole compared to university hospitals. Standard treatments for recurrent infection were vancomycin orally (40â% alone, 29.1â% combined with metronidazole) or, more rarely, fidaxomicin (25.5â%). Fidaxomicin has been used at least once at the ICU in 79â% of the respondents. Eleven percent have used fecal microbiota transplant (FMT) in selected cases at the ICU. CONCLUSION: Our survey indicated a high awareness of German intensivists for Clostridium difficile infections, but also marked differences in local therapeutic algorithms, especially in first-line treatment.
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Clostridioides difficile , Infecciones por Clostridium , Adhesión a Directriz , Infecciones por Clostridium/diagnóstico , Infecciones por Clostridium/mortalidad , Infecciones por Clostridium/terapia , Alemania , Humanos , Unidades de Cuidados Intensivos , Encuestas y CuestionariosRESUMEN
OBJECTIVES: The liver's capability to completely regenerate after injury is a unique phenomenon in which cytokines are of particular interest. Here, we aimed to assess the release patterns and prognostic relevance of liver regeneration-related cytokines in the setting of living-donor liver transplant. MATERIALS AND METHODS: Eleven cytokines related to liver regeneration (hepatocyte growth factor, interleukin 6, insulin-like growth factor-1, tumor necrosis factor alpha, transforming growth factor beta, granulocyte colony-stimulating factor, stem cell factor, chemokine (C-X-C motif) ligand 12, angiogenin, fibroblast growth factor-2, and vascular endothelial growth factor) were compared in 13 living-donor liver transplant recipients and their corresponding donors before and daily (10 days) after transplant. Patients and donors were stratified by clinical outcomes (early graft loss within 4 weeks after transplant vs beneficial outcome). RESULTS: Most cytokines tested (especially tumor necrosis factor alpha and stem cell factor) were elevated in recipients versus donors. Many cytokines were also increased in recipients with graft loss (especially CXCL12) and in donors of recipients with beneficial outcomes (especially fibroblast growth factor 2). Fibroblast growth factor 2 levels were also correlated positively with serum gamma-glutamyltransferase, and higher preoperative concentrations in donors were associated with recipients having beneficial outcomes, indicating an improved regenerative capacity. In contrast, elevated CXCL12 levels in recipients before and after LDLT predicted graft loss and were linked to ongoing liver damage. CONCLUSIONS: In living-donor liver transplant, there are distinct differences between donors and recipients regarding the release of liver regeneration-related cytokines. Moreover, fibroblast growth factor 2 and CXCL12 may be of diagnostic value in a complementary way to describe or even predict the possible outcomes after transplant. These results may be of clinical interest not only for living-donor liver transplant but also for acute liver failure.
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Citocinas/sangre , Regeneración Hepática , Trasplante de Hígado/métodos , Donadores Vivos , Receptores de Trasplantes , Adulto , Anciano , Biomarcadores/sangre , Proliferación Celular , Quimiocina CXCL12/sangre , Femenino , Factor 2 de Crecimiento de Fibroblastos/sangre , Hepatectomía , Humanos , Trasplante de Hígado/efectos adversos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Valor Predictivo de las Pruebas , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Adulto JovenAsunto(s)
Antibacterianos/administración & dosificación , Antibacterianos/efectos adversos , Infecciones Comunitarias Adquiridas/diagnóstico , Infecciones Comunitarias Adquiridas/prevención & control , Enterocolitis Seudomembranosa/diagnóstico , Enterocolitis Seudomembranosa/prevención & control , Inmunoensayo/métodos , Colitis , Infecciones Comunitarias Adquiridas/etiología , Enterocolitis Seudomembranosa/etiología , Medicina Basada en la Evidencia , Humanos , Resultado del TratamientoRESUMEN
Background: The arising challenges over endoscope reprocessing quality proposes to look for possibilities to measure and control the process of endoscope reprocessing. Aim: The goal of this study was to evaluate the feasibility of monitoring endoscope reprocessing with an adenosine triphosphate (ATP) based bioluminescence system. Methods: 60 samples of eight gastroscopes have been assessed from routine clinical use in a major university hospital in Germany. Endoscopes have been assessed with an ATP system and microbial cultures at different timepoints during the reprocessing. Findings: After the bedside flush the mean ATP level in relative light units (RLU) was 19,437 RLU, after the manual cleaning 667 RLU and after the automated endoscope reprocessor (AER) 227 RLU. After the manual cleaning the mean total viable count (TVC) per endoscope was 15.3 CFU/10 ml, and after the AER 5.7 CFU/10 ml. Our results show that there are reprocessing cycles which are not able to clean a patient used endoscope. Conclusion: Our data suggest that monitoring of flexible endoscope with ATP can identify a number of different influence factors, like the endoscope condition and the endoscopic procedure, or especially the quality of the bedside flush and manual cleaning before the AER. More process control is one option to identify and improve influence factors to finally increase the overall reprocessing quality, best of all by different methods. ATP measurement seems to be a valid technique that allows an immediate repeat of the manual cleaning if the ATP results after manual cleaning exceed the established cutoff of 200 RLU.
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Fármacos Anti-VIH/administración & dosificación , Infecciones por VIH/prevención & control , Profilaxis Pre-Exposición/métodos , Tenofovir/administración & dosificación , Adulto , ADN Viral/sangre , VIH-1/aislamiento & purificación , Hepatitis B/complicaciones , Virus de la Hepatitis B/aislamiento & purificación , Humanos , Masculino , ARN Viral/sangre , Sífilis/complicaciones , Insuficiencia del Tratamiento , Carga ViralRESUMEN
BACKGROUND/AIMS: Portal hypertension (PH) is a common complication of chronic liver disease and results in esophageal and gastric variceal bleeding, which is associated with a high mortality rate. Measurement of the hepatic venous pressure gradient (HVPG) is considered the gold standard for diagnosing PH and estimating the risk of varices and bleeding. In contrast, upper gastrointestinal (GI) endoscopy (UGE) can reliably demonstrate the presence of varices and bleeding. Both measures are invasive, and HVPG is mainly restricted to tertiary centers. Therefore, the development of noninvasive methods of assessing the severity of PH and the risk of variceal bleeding is warranted. METHODS: We retrospectively examined the correlation of spleen stiffness (SSM) and liver stiffness measurements (LSM) with the incidence of variceal bleeding among 143 patients who underwent combined liver and spleen elastography between 2013 and 2015. RESULTS: For 19 of 103 patients (16.8%), upper GI variceal bleeding was diagnosed and treated endoscopically. The median SSM of all patients was 35.3 kilopascals (kPa); the median LSM, 11.7 kPa. Patients with previous bleeding episodes had significantly higher SSM (75.0 kPa) and LSM (37.3 kPa) than those without a history of bleeding (SSM, 30.6 kPa; LSM, 8.2 kPa; p < 0.0001). Seventy-five patients (66.4%) underwent UGE in addition to SSM and LSM: 25 with no esophageal varices (EVs; SSM, 29.5 kPa; LSM, 11.4 kPa), 16 with EV grade 1 (SSM, 35.9 kPa; LSM, 33.4 kPa), 21 with EV grade 2 (SSM, 67.8 kPa; LSM, 27.0 kPa) and 13 with EV grade 3 (SSM, 75.0 kPa; LSM, 26.3 kPa). No statistically significant differences were found between respective grades of EV but were found between the presence and absence of varices. At a calculated cutoff level of 42.6 kPa (with application of 95% CI), SSM had sensitivity of 89% and specificity of 64% in determining the risk of bleeding, with a negative predictive value (NPV) of 0.97 (LSM sensitivity, 84%; LSM specificity, 80%; LSM NPV, 0.96 at LSM cutoff level of 20.8 kPa). When LSM (cutoff level, 20.8 kPa) and SSM (cutoff level, 42.6 kPa) were combined, the NPV was 1 (sensitivity, 100%; specificity, 55%). CONCLUSION: SSM and LSM as determined by FibroScan (a noninvasive method of detecting PH) is positively correlated with upper GI variceal bleeding (optimal SSM cutoff level, 42.6 kPa; optimal LSM cutoff level, 20.8 kPa). No patients with both SSM and LSM below cutoff levels had a history of bleeding complications.
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Várices Esofágicas y Gástricas/epidemiología , Hemorragia Gastrointestinal/epidemiología , Hepatopatías/complicaciones , Hígado/fisiopatología , Bazo/fisiopatología , Enfermedad Crónica , Diagnóstico por Imagen de Elasticidad/métodos , Várices Esofágicas y Gástricas/etiología , Várices Esofágicas y Gástricas/patología , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiología , Alemania/epidemiología , Humanos , Incidencia , Presión Portal , Estudios Retrospectivos , Medición de RiesgoRESUMEN
UNLABELLED: Activation of hepatitis B virus (HBV)-specific CD8 T cells by therapeutic vaccination may promote sustained control of viral replication by clearance of covalently closed circular DNA from infected hepatocytes. However, little is known about the exact targets of the CD8 T-cell response and whether HBV reproducibly evades CD8 T-cell immune pressure by mutation. The aim of this study was to address if HBV reproducibly selects substitutions in CD8 T-cell epitopes that functionally act as immune escape mutations. The HBV core gene was amplified and sequenced from 148 patients with chronic HBV infection, and the human leukocyte antigen (HLA) class I genotype (A and B loci) was determined. Residues under selection pressure in the presence of particular HLA class I alleles were identified by a statistical approach utilizing the novel analysis package SeqFeatR. With this approach we identified nine residues in HBV core under selection pressure in the presence of 10 different HLA class I alleles. Additional immunological experiments confirmed that seven of the residues were located inside epitopes targeted by patients with chronic HBV infection carrying the relevant HLA class I allele. Consistent with viral escape, the selected substitutions reproducibly impaired recognition by HBV-specific CD8 T cells. CONCLUSION: Viral sequence analysis allows identification of HLA class I-restricted epitopes under reproducible selection pressure in HBV core; the possibility of viral escape from CD8 T-cell immune pressure needs attention in the context of therapeutic vaccination against HBV.
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Linfocitos T CD8-positivos/fisiología , Genes MHC Clase I , Virus de la Hepatitis B/genética , Selección Genética , Proteínas del Núcleo Viral/genética , Adaptación Biológica , Epítopos de Linfocito T , Hepatitis B Crónica/inmunología , Hepatitis B Crónica/virología , HumanosRESUMEN
BACKGROUND & AIMS: CD8(+) T cells are an essential component of a successful immune response against hepatitis B virus (HBV). Patients who spontaneously clear HBsAg after acute HBV infection have a strong CD8(+) T cell immune response, predominantly directed against the HBV core protein (HBcAg). However, the fate and phenotype of HBcAg-specific CD8(+) T cells after immune control are unclear. METHODS: The CD8(+) T cell immune response against HBV core was determined in 65 patients with chronic HBV infection, 16 patients after recovery from acute HBV infection, and four patients with acute HBV infection utilizing overlapping peptides and HLA class I/peptide-multimers. RESULTS: Patients who had cleared HBsAg >30 years ago had significantly weaker CD8(+) T cell responses after antigen-specific expansion compared to patients who had cleared the virus <10 years ago and patients with HBeAg negative chronic infection and low viral load (<2000 IU/ml; p<0.01). Also directly ex vivo, patients who had cleared the HBsAg >30 years ago had less HBV-specific CD8(+) T cells compared to patients with HBeAg negative chronic infection (p=0.0025). In patients with acute HBV infection, the frequency of HBc-specific CD8(+) T cells continued to decline after clearance of HBV-DNA and HBsAg even at a time when ALT levels had already normalized (p=0.0313). CONCLUSIONS: The frequency of HBcAg-specific CD8(+) T cells continuously declines after HBsAg clearance. In line with clinical observations, this suggests that humoral and not CD8(+) T cell immune responses mainly contribute to prevention of HBV reactivation decades after HBsAg clearance.
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Linfocitos T CD8-positivos/inmunología , Antígenos de Superficie de la Hepatitis B/inmunología , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/inmunología , Hígado/virología , Adulto , Femenino , Anticuerpos contra la Hepatitis B/inmunología , Hepatitis B Crónica/virología , Humanos , Hígado/inmunología , Masculino , Persona de Mediana Edad , Carga ViralRESUMEN
BACKGROUND: Graft loss because of hepatitis C virus recurrence is a serious problem after liver transplantation (LT), and the response to pegylated interferon (PEG-IFN) and ribavirin (RBV) is poor. The significantly better response rates achieved with telaprevir (TVR)-based triple therapy have led to better graft and patient survival rates, but severe drug interactions may limit the usefulness of this therapy for LT patients. We report our single-center experience with a specially developed protocol that involved administering a low daily dose of tacrolimus (TAC) to a cohort of 17 patients with a recurrence of hepatitis C virus genotype 1 after LT. METHODS: Patients were treated with TVR, PEG-IFN, and RBV for 12 weeks, followed by 12 or 36 weeks of dual therapy with PEG-IFN and RBV. After TVR administration was initiated, the TAC dosage was skipped until trough levels began to decline; it was then administered at a dose of 0.1 mg once or twice daily. Tacrolimus trough levels and laboratory values were closely monitored during the TVR phase. RESULTS: Deviations in trough levels were avoided, thus preventing any clinically evident renal toxicity related to TAC. In addition, histologic studies performed at the end of therapy showed that no rejection episodes had occurred. All patients tolerated the medication. Sustained virologic response was documented for 10 of 17 patients (58%) 24 weeks after end of treatment. CONCLUSION: In conclusion, substantial dose reduction and daily administration of low doses of TAC compose a safe and efficient immunosuppressive regimen during TVR-based triple therapy.