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1.
J Virol ; 92(2)2018 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-29093082

RESUMEN

Hepatitis C virus (HCV)-specific CD8+ T cells suffer a progressive exhaustion during persistent infection (PI) with HCV. This process could involve the positive immune checkpoint 4-1BB/4-1BBL through the loss of its signal transducer, TRAF1. To address this issue, peripheral HCV-specific CD8+ T cells (pentamer-positive [pentamer+]/CD8+ T cells) from patients with PI and resolved infection (RI) after treatment were studied. The duration of HCV infection and the liver fibrosis progression rate inversely correlated with the likelihood of detection of peripheral pentamer+/CD8+ cells. In PI, pentamer+/CD8+ cells had impaired antigen-specific reactivity that worsened when these cells were not detectable ex vivo Short/midduration PI was characterized by detectable peripheral PD-1+ CD127low TRAF1low cells. After triggering of T cell receptors (TCR), the TRAF1 level positively correlated with the levels of CD127, Mcl-1, and CD107a expression and proliferation intensity but negatively with PD-1 expression, linking TRAF1low to exhaustion. In vitro treatment with interleukin-7 (IL-7) upregulated TRAF1 expression, while treatment with transforming growth factor-ß1 (TGF-ß1) did the opposite, suggesting that the IL-7/TGF-ß1 balance, besides TCR stimulation, could be involved in TRAF1 regulation. In fact, the serum TGF-ß1 concentration was higher in patients with PI than in patients with RI, and it negatively correlated with TRAF1 expression. In line with IL-7 increasing the level of TRAF1 expression, IL-7 plus 4-1BBL treatment in vitro enhanced T cell reactivity in patients with short/midduration infection. However, in patients with long-lasting PI, anti-PD-L1, in addition to the combination of IL-7 and 4-1BBL, was necessary to reestablish T cell proliferation in individuals with slowly progressing liver fibrosis (slow fibrosers) but had no effect in rapid fibrosers. In conclusion, a peripheral hyporeactive TRAF1low HCV-specific CD8+ T cell response, restorable by IL-7 plus 4-1BBL treatment, characterizes short/midduration PI. In long-lasting disease, HCV-specific CD8+ T cells are rarely detectable ex vivo, but treatment with IL-7, 4-1BBL, and anti-PD-L1 recovers their reactivity in vitro in slow fibrosers.IMPORTANCE Hepatitis C virus (HCV) infects 71 million people worldwide. Two-thirds develop a chronic disease that can lead to cirrhosis and hepatocellular carcinoma. Direct-acting antivirals clear the infection, but there are still patients who relapse. In these cases, additional immunotherapy could play a vital role. A successful anti-HCV immune response depends on virus-specific CD8+ T cells. During chronic infection, these cells are functionally impaired, which could be due to the failure of costimulation. This study describes exhausted specific T cells, characterized by low levels of expression of the signal transducer TRAF1 of the positive costimulatory pathway 4-1BB/4-1BBL. IL-7 upregulated TRAF1 expression and improved T cell reactivity in patients with short/midduration disease, while in patients with long-lasting infection, it was also necessary to block the negative PD-1/PD-L1 checkpoint. When the results are taken together, this work supports novel ways of restoring the specific CD8+ T cell response, shedding light on the importance of TRAF1 signaling. This could be a promising target for future immunotherapy.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Hepacivirus/fisiología , Hepatitis C/inmunología , Hepatitis C/metabolismo , Interleucina-7/metabolismo , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/metabolismo , Anciano , Progresión de la Enfermedad , Epítopos de Linfocito T/química , Epítopos de Linfocito T/inmunología , Femenino , Citometría de Flujo , Expresión Génica , Genotipo , Hepatitis C/complicaciones , Hepatitis C/virología , Humanos , Cirrosis Hepática/etiología , Activación de Linfocitos/inmunología , Masculino , Persona de Mediana Edad , Fenotipo , Receptor de Muerte Celular Programada 1/genética , Receptor de Muerte Celular Programada 1/metabolismo , Unión Proteica , Factor 1 Asociado a Receptor de TNF/metabolismo
2.
Rev Esp Enferm Dig ; 108(10): 680-683, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27650893

RESUMEN

Interventional endoscopy is a field that continues to grow rapidly. A novel prototype forward-viewing echoendoscope (FV-EUS) has been recently developed in an attempt to overcome some of the limitations of conventional curved linear-array echoendoscopes (OV-EUS). We present a case of a successful endoscopic ultrasound-guided drainage of a pancreatic pseudocyst using a forward-viewing echoendoscope. Although the utilization use of this newly developed echoendoscope has not yet become widespread, its unique characteristics can help to easily perform routine therapeutic procedures and contribute to the expansion of interventional endoscopic utrasoundultrasound.


Asunto(s)
Drenaje , Endoscopios Gastrointestinales , Endosonografía/métodos , Seudoquiste Pancreático/diagnóstico por imagen , Seudoquiste Pancreático/terapia , Adulto , Endoscopía Gastrointestinal , Endosonografía/instrumentación , Diseño de Equipo , Femenino , Humanos
3.
Front Immunol ; 15: 1352929, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38545116

RESUMEN

Background: HBe-antigen(Ag)-negative chronic hepatitis B virus (HBV) infection is characterized by little liver fibrosis progression and vigorous HBV-multispecific CD8+ T-cell response. Aims: To assess whether HBsAg level could discriminate different HBeAg-negative chronic HBV infection subtypes with dissimilar quality of HBV-specific CD8+ T-cell response. Methods: We recruited 63 HBeAg-negative chronic HBV infection patients in which indirect markers of liver inflammation/fibrosis, portal pressure, viral load (VL), and HBV-specific CD8+ cell effector function were correlated with HBsAg level. Results: A positive linear trend between HBsAg level and APRI, liver stiffness (LS), liver transaminases, and HBV VL, and a negative correlation with platelet count were observed. Frequency of cases with HBV-specific CD8+ T-cell proliferation against at least two HBV epitopes was higher in HBsAg < 1,000 IU/ml group. CD8+ T-cell expansion after HBVpolymerase456-63-specific stimulation was impaired in HBsAg > 1,000 IU/ml group, while the response against HBVcore18-27 was preserved and response against envelope183-91 was nearly abolished, regardless of HBsAg level. Cases with preserved HBVpolymerase456-63 CD8+ cell response had lower LS/duration of infection and APRI/duration of infection rates. HBV-polymerase456-63-specific CD8+ T-cell proliferation intensity was negatively correlated with LS/years of infection ratio. Conclusion: HBsAg > 1,000 IU/ml HBeAg-negative chronic HBV infection group shows indirect data of higher degree of inflammation, liver stiffness, and fibrosis progression speed, which are related to an impaired HBV-polymerase-specific CD8+ T-cell response.


Asunto(s)
Productos del Gen pol , Hepatitis B Crónica , Humanos , Virus de la Hepatitis B/fisiología , Antígenos de Superficie de la Hepatitis B/genética , Antígenos e de la Hepatitis B/genética , Inflamación , Cirrosis Hepática , Linfocitos T CD8-positivos , Alanina Transaminasa , Fenotipo
4.
iScience ; 27(1): 108666, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38155778

RESUMEN

A rebalance between energy supply and demand in HBV-specific-CD8+ activated progenitor (AP) cells could restore the functionality of proliferative progeny (PP) in e-antigen(Ag)-negative chronic hepatitis B (CHBe(-)). We observed that quiescent progenitor (QP [TCF1+/FSClow]) HBVcore-specific-CD8+ cells displayed a memory-like phenotype. Following Ag-encounter, the generated AP [TCF1+/FSChigh] subset maintained the PD1+/CD127+ phenotype and gave rise to proliferative progeny (PP [ TCF1-/FSChigh]). In AP cells, IL-15 compared to IL2 decreased the initial mTORC1 boost, but maintained its activation longer linked to a catabolic profile that correlated with enhanced PP effector abilities. In nucleos(t)ide analogue (NUC)-treated CHBe(-), AP subset showed an anabolic phenotype associated with a dysfunctional PP pool. In CHBe(-) cases with low probability of HBVcore-specific-CD8+ cell on-NUC-treatment restoration, according to a clinical predictive model, IL-15/anti-PD-L1 treatment re-established their reactivity. Therefore, IL-15 could improve AP pool energy balance by decreasing intensity but extending T cell activation and by inducing a more catabolic metabolism.

5.
Cell Immunol ; 286(1-2): 31-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24287274

RESUMEN

Lower than 2-log viral-load (VL) decrease at week 12 (w12) of chronic hepatitis C (CHC) treatment with Peg-interferon/ribavirin has 100% negative predictive value (PV) of sustained virologic response (SVR), and this could be related with absence of HCV-specific cytotoxic T lymphocyte (CTL) response. In this study, percentage of cases with SVR, according to peripheral HCV-specific cytotoxic response at w12, was analysed (Group-1: detection(+), Group-2: detection(-)). SVR was higher in group-1 (93%) than in group-2 (47%) (p=0.003). An increase on HCV-specific CTL frequency between baseline and w12 and higher specific reactivity were observed in group-1 (p=0.011 and p=0.025). HCV-specific CTL detection at w12 correlated with level of VL decrease (p=0.016, r=0.389), and among HCV genotype-1 patients with either early or delayed virologic response (EDVR), 100% positive PV of SVR was observed. In summary, HCV-specific CTL detection at w12 of Peg-interferon/ribavirin treatment correlates with SVR and in EDVR genotype-1 cases predicts SVR.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/diagnóstico , Interferón-alfa/uso terapéutico , Polietilenglicoles/uso terapéutico , ARN Viral/antagonistas & inhibidores , Ribavirina/uso terapéutico , Linfocitos T Citotóxicos/inmunología , Adulto , Biomarcadores/análisis , Quimioterapia Combinada , Femenino , Hepacivirus/efectos de los fármacos , Hepacivirus/inmunología , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/inmunología , Hepatitis C Crónica/virología , Humanos , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , ARN Viral/inmunología , Proteínas Recombinantes/uso terapéutico , Linfocitos T Citotóxicos/efectos de los fármacos , Linfocitos T Citotóxicos/virología , Resultado del Tratamiento , Carga Viral/efectos de los fármacos
6.
Curr Biol ; 32(23): 5083-5098.e6, 2022 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-36379215

RESUMEN

Programmed DNA elimination (PDE) is a notable exception to the paradigm of genome integrity. In metazoa, PDE often occurs coincident with germline to somatic cell differentiation. During PDE, portions of genomic DNA are lost, resulting in reduced somatic genomes. Prior studies have described the sequences lost, as well as chromosome behavior, during metazoan PDE. However, a system for studying the mechanisms and consequences of PDE in metazoa is lacking. Here, we present a functional and genetic model for PDE in the free-living Rhabditidae nematode Oscheius tipulae, a family that also includes Caenorhabditis elegans. O. tipulae was recently suggested to eliminate DNA. Using staged embryos and DNA FISH, we showed that O. tipulae PDE occurs during embryogenesis at the 8-16 cell stages. We identified a conserved motif, named Sequence For Elimination (SFE), for all 12 break sites on the six chromosomes at the junctions of retained and eliminated DNA. SFE mutants exhibited a "fail-to-eliminate" phenotype only at the modified sites. END-seq revealed that breaks can occur at multiple positions within the SFE, with extensive end resection followed by telomere addition to both retained and eliminated ends. We identified many functional SFEs at the chromosome ends through END-seq in the wild-type embryos, genome sequencing of SFE mutants, and comparative genomics of 23 wild isolates. We suggest that these alternative SFEs provide flexibility in the sequences eliminated and a fail-safe mechanism for PDE. These studies establish O. tipulae as a new, attractive model for studying the mechanisms and consequences of PDE in a metazoan.


Asunto(s)
Genómica , Modelos Genéticos , Animales , ADN
7.
Aliment Pharmacol Ther ; 55(12): 1545-1559, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35224746

RESUMEN

BACKGROUND: Hepatitis B virus (HBV)-specific CD8+ cell response restoration during nucleos(t)ide analogue (NUC) treatment could lead to off-treatment HBV control in e-antigen-negative chronic hepatitis B (CHBe(-)). AIM: To predict this response with variables involved in T-cell exhaustion for use as a treatment stopping tool. METHODS: In NUC-treated CHBe(-) patients, we considered a functional response in cases with HBV-specific CD8+ cells against core and polymerase HBV epitopes able to proliferate and secrete type I cytokines after antigen encounter. We performed a logistic regression model (LRM) to predict the likelihood of developing this response, based on patient age (subrogate of infection length), HBsAg level, NUC therapy starting point and duration (antigenic pressure). We discontinued treatment and assessed HBV DNA dynamics, HBsAg decline and loss during off-treatment follow-up according to LRM likelihood. RESULTS: We developed an LRM that predicted the presence of a proliferative type I cytokine-secreting CD8+ cell response, which correlated positively with treatment duration and negatively with treatment initiation after the age of 40 years and with age adjusted by HBsAg level. We observed a positive correlation between LRM probability and intensity of proliferation, number of epitopes with the functional proliferating response and type I cytokine secretion level. Off-treatment, HBsAg loss, HBsAg decline >50% and HBV control were more frequent in the group with >90% LRM probability. CONCLUSIONS: Short-term low-level antigen exposure and early long-term NUC treatment influence the restoration of a functional HBV-specific CD8+ cell response. Based on these predictors, a high likelihood of detecting this response at treatment withdrawal is associated with off-treatment HBV control and HBsAg decline and loss.


Asunto(s)
Hepatitis B Crónica , Adulto , Antivirales/uso terapéutico , Linfocitos T CD8-positivos , Citocinas , ADN Viral/genética , Epítopos , Antígenos de Superficie de la Hepatitis B , Antígenos e de la Hepatitis B , Virus de la Hepatitis B/genética , Humanos , Resultado del Tratamiento
8.
Cell Immunol ; 269(2): 104-14, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21481848

RESUMEN

PD-1 molecule promotes anergy and IL-7 receptor (CD127) induces an anti-apoptotic effect on T cells. Correlation between PD-1/CD127 phenotype and hepatitis C virus (HCV)-specific CD8(+) cell reactivity in resolved infection (RI) after treatment and persistent HCV-infection (PI) was analysed. Directly ex vivo, PD-1 and CD127 expression on HCV-specific CD8(+) cells displayed a positive and negative correlation, respectively with viraemia. Proliferation after stimulation on PD-1(-)/CD127(+) cells from RI cases was preserved, while it was impaired on PD-1(+)/CD127(-) cells from PI patients. PD1(+)/CD127(+) population was observed in PI, and these maintained expansion ability but they did not target the virus. Frequency of PI cases with HCV-specific CD8(+) cell proliferation increased after anti-PD-L1 and anti-apoptotic treatment. Bim expression on HCV-specific CD8(+) cells from PI patients was enhanced. In conclusion, during chronic HCV infection non-reactive HCV-specific CD8(+) cells targeting the virus are PD-1(+)/CD127(-)/Bim(+) and, blocking apoptosis and PD-1/PD-L1 pathway on them enhances in vitro reactivity.


Asunto(s)
Antígenos CD/metabolismo , Proteínas Reguladoras de la Apoptosis/metabolismo , Apoptosis/inmunología , Hepatitis C Crónica/inmunología , Subunidad alfa del Receptor de Interleucina-7/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Linfocitos T Citotóxicos/inmunología , Adulto , Clorometilcetonas de Aminoácidos/farmacología , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/farmacología , Antígenos CD/inmunología , Apoptosis/efectos de los fármacos , Antígeno B7-H1 , Proteína 11 Similar a Bcl2 , Recuento de Células , Proliferación Celular/efectos de los fármacos , Femenino , Humanos , Inmunofenotipificación , Hígado/inmunología , Hígado/patología , Activación de Linfocitos/efectos de los fármacos , Activación de Linfocitos/inmunología , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Receptor de Muerte Celular Programada 1 , Transducción de Señal/efectos de los fármacos , Transducción de Señal/inmunología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Subgrupos de Linfocitos T/fisiología , Linfocitos T Citotóxicos/metabolismo , Linfocitos T Citotóxicos/patología , Carga Viral/inmunología , Proteínas no Estructurales Virales/inmunología
9.
Cells ; 10(3)2021 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-33802622

RESUMEN

Hepatitis C virus (HCV)-specific CD8+ T cell response is essential in natural HCV infection control, but it becomes exhausted during persistent infection. Nowadays, chronic HCV infection can be resolved by direct acting anti-viral treatment, but there are still some non-responders that could benefit from CD8+ T cell response restoration. To become fully reactive, T cell needs the complete release of T cell receptor (TCR) signalling but, during exhaustion this is blocked by the PD-1 effect on CD28 triggering. The T cell pool sensitive to PD-1 modulation is the progenitor subset but not the terminally differentiated effector population. Nevertheless, the blockade of PD-1/PD-L1 checkpoint cannot be always enough to restore this pool. This is due to the HCV ability to impair other co-stimulatory mechanisms and metabolic pathways and to induce a pro-apoptotic state besides the TCR signalling impairment. In this sense, gamma-chain receptor cytokines involved in memory generation and maintenance, such as low-level IL-2, IL-7, IL-15, and IL-21, might carry out a positive effect on metabolic reprogramming, apoptosis blockade and restoration of co-stimulatory signalling. This review sheds light on the role of combinatory immunotherapeutic strategies to restore a reactive anti-HCV T cell response based on the mixture of PD-1 blocking plus IL-2/IL-7/IL-15/IL-21 treatment.


Asunto(s)
Antígeno B7-H1/genética , Hepacivirus/inmunología , Hepatitis C Crónica/tratamiento farmacológico , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inmunoterapia/métodos , Receptor de Muerte Celular Programada 1/genética , Receptores de Antígenos de Linfocitos T gamma-delta/genética , Anticuerpos Monoclonales/uso terapéutico , Antígeno B7-H1/antagonistas & inhibidores , Antígeno B7-H1/inmunología , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/virología , Regulación de la Expresión Génica , Hepacivirus/patogenicidad , Hepatitis C Crónica/genética , Hepatitis C Crónica/inmunología , Hepatitis C Crónica/virología , Interacciones Huésped-Patógeno/efectos de los fármacos , Interacciones Huésped-Patógeno/genética , Interacciones Huésped-Patógeno/inmunología , Humanos , Inmunidad Celular/efectos de los fármacos , Interleucinas/genética , Interleucinas/inmunología , Interleucinas/uso terapéutico , Activación de Linfocitos/efectos de los fármacos , Células Precursoras de Linfocitos T/efectos de los fármacos , Células Precursoras de Linfocitos T/inmunología , Células Precursoras de Linfocitos T/virología , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/inmunología , Receptores de Antígenos de Linfocitos T gamma-delta/agonistas , Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Transducción de Señal
10.
Cancers (Basel) ; 13(8)2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33923463

RESUMEN

Thirty to fifty percent of hepatocellular carcinomas (HCC) display an immune class genetic signature. In this type of tumor, HCC-specific CD8 T cells carry out a key role in HCC control. Those potential reactive HCC-specific CD8 T cells recognize either HCC immunogenic neoantigens or aberrantly expressed host's antigens, but they become progressively exhausted or deleted. These cells express the negative immunoregulatory checkpoint programmed cell death protein 1 (PD-1) which impairs T cell receptor signaling by blocking the CD28 positive co-stimulatory signal. The pool of CD8 cells sensitive to anti-PD-1/PD-L1 treatment is the PD-1dim memory-like precursor pool that gives rise to the effector subset involved in HCC control. Due to the epigenetic imprints that are transmitted to the next generation, the effect of PD-1 blockade is transient, and repeated treatments lead to tumor resistance. During long-lasting disease, besides the TCR signaling impairment, T cells develop other failures that should be also set-up to increase T cell reactivity. Therefore, several PD-1 blockade-based combinatory therapies are currently under investigation such as adding antiangiogenics, anti-TGFß1, blockade of other negative immune checkpoints, or increasing HCC antigen presentation. The effect of these combinations on CD8+ T cells is discussed in this review.

11.
Rev Med Inst Mex Seguro Soc ; 48(2): 133-8, 2010.
Artículo en Español | MEDLINE | ID: mdl-20929615

RESUMEN

BACKGROUND: There are no reliable and valid instruments in Mexico for breast cancer patients. Our objective was to measure reliability and validity of a Spanish version of the FACT-B (Functional Assessment of Cancer Therapy-Breast) questionnaire in Mexican population. METHODS: The translation of the questionnaire was reviewed and minor changes were made. The instrument was applied to 142 patients recently diagnosed with breast cancer. It was applied to 105 for the second time, and to 75 for the third time. An analysis of item discrimination was made. The questionnaire's reliability was determined by Cronbach's alpha. Concurrent validity was determined by an analysis of correlations between the instrument's scales and EORTC's QLQ C-30 y BR-23 scales. RESULTS: The five FACT-B subscales were reliable, their alpha coefficients varied between 0.65 and 0.82. The entire scale obtained a value of 0.87. The correlation analysis between FACT-B and EORTC QLQ C-30 subscales indicated that the same construct was being evaluated. CONCLUSIONS: FACT-B is a valid, reliable and sensitive instrument to measuring quality life in Mexican breast cancer patients.


Asunto(s)
Neoplasias de la Mama , Calidad de Vida , Encuestas y Cuestionarios , Neoplasias de la Mama/diagnóstico , Femenino , Humanos , Estudios Prospectivos
12.
World J Hepatol ; 12(10): 754-765, 2020 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-33200014

RESUMEN

Hepatitis C virus (HCV) infection is an excellent immunological model for understanding the mechanisms developed by non-cytopathic viruses and tumors to evade the adaptative immune response. The antigen-specific cytotoxic T cell response is essential for keeping HCV under control, but during persistent infection, these cells become exhausted or even deleted. The exhaustion process is progressive and depends on the infection duration and level of antigenemia. During high antigenic load and long duration of infection, T cells become extremely exhausted and ultimately disappear due to apoptosis. The development of exhaustion involves the impairment of positive co-stimulation induced by regulatory cytokines, such as transforming growth factor beta 1. This cytokine downregulates tumor necrosis factor receptor (TNFR)-associated factor 1 (TRAF1), the signal transducer of the T cell co-stimulatory molecule TNFR superfamily member 9 (known as 4-1BB). This impairment correlates with the low reactivity of T cells and an exhaustion phenotype. Treatment with interleukin-7 in vitro restores TRAF1 expression and rescues T cell effector function. The process of TRAF1 loss and its in vitro recovery is hierarchical, and more affected by severe disease progression. In conclusion, TRAF1 dynamics on T cells define a new pathogenic model that describes some aspects of the natural history of HCV, and sheds light on novel immunotherapy strategies for chronic viral infections and cancer.

13.
World J Gastroenterol ; 14(47): 7149-59, 2008 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-19084927

RESUMEN

Chemokines produced in the liver during hepatitis C virus (HCV) infection induce migration of activated T cells from the periphery to infected parenchyma. The milieu of chemokines secreted by infected hepatocytes is predominantly associated with the T-helper cell/Tc1 T cell (Th1/Tc1) response. These chemokines consist of CCL3 (macrophage inflammatory protein-1 alpha; MIP-1 alpha), CCL4 (MIP-1 beta), CCL5 (regulated on activation normal T cell expressed and secreted; RANTES), CXCL10 (interferon-gamma-inducible protein-10; IP-10), CXCL11 (interferon-inducible T-cell alpha chemoattractant; I-TAC), and CXCL9 (monokine induced by interferon gamma; Mig) and they recruit T cells expressing either CCR5 or CXCR3 chemokine receptors. Intrahepatic and peripheral blood levels of these chemokines are increased during chronic hepatitis C. The interaction between chemokines and their receptors is essential in recruiting HCV-specific T cells to control the infection. When the adaptive immune response fails in this task, non-specific T cells without the capacity to control the infection are also recruited to the liver, and these are ultimately responsible for the persistent hepatic damage. The modulation of chemokine receptor expression and chemokine secretion could be a viral escape mechanism to avoid specific T cell migration to the liver during the early phase of infection, and to maintain liver viability during the chronic phase, by impairing non-specific T cell migration. Some chemokines and their receptors correlate with liver damage, and CXCL10 (IP-10) and CXCR3 levels have shown a clinical utility as predictors of treatment response outcome. The regulation of chemokines and their receptors could be a future potential therapeutic target to decrease liver inflammation and to increase specific T cell migration to the infected liver.


Asunto(s)
Quimiocinas/fisiología , Hepatitis C Crónica/fisiopatología , Hígado/virología , Receptores de Quimiocina/fisiología , Animales , Antivirales/uso terapéutico , Modelos Animales de Enfermedad , Hepacivirus/patogenicidad , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Hígado/fisiopatología , Resultado del Tratamiento
14.
World J Gastroenterol ; 24(17): 1825-1838, 2018 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-29740199

RESUMEN

Chronic hepatitis B (CHB) remains a challenging global health problem, with nearly one million related deaths per year. Nucleos(t)ide analogue (NA) treatment suppresses viral replication but does not provide complete cure of the hepatitis B virus (HBV) infection. The accepted endpoint for therapy is the loss of hepatitis B surface antigen (HBsAg), but this is hardly ever achieved. Therefore, indefinite treatment is usually required. Many different studies have evaluated NA therapy discontinuation after several years of NA treatment and before HBsAg loss. The results have indicated that the majority of patients can remain off therapy, with some even reaching HBsAg seroconversion. Fortunately, this strategy has proved to be safe, but it is essential to consider the risk of liver damage and other comorbidities and to ensure a close follow-up of the candidates before considering this strategy. Unanswered questions remain, namely in which patients could this strategy be effective and what is the optimal time point at which to perform it. To solve this enigma, we should keep in mind that the outcome will ultimately depend on the equilibrium between HBV and the host's immune system. Viral parameters that have been described as good predictors of response in HBeAg(+) cases, have proven useless in HBeAg(-) ones. Since antiviral immunity plays an essential role in the control of HBV infection, we sought to review and explain potential immunological biomarkers to predict safe NA discontinuation in both groups.


Asunto(s)
Antivirales/uso terapéutico , Antígenos de Superficie de la Hepatitis B/aislamiento & purificación , Virus de la Hepatitis B/fisiología , Hepatitis B Crónica/tratamiento farmacológico , Privación de Tratamiento/normas , Antivirales/farmacología , Antígenos de Superficie de la Hepatitis B/inmunología , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/sangre , Hepatitis B Crónica/virología , Humanos , Nucleósidos/farmacología , Nucleósidos/uso terapéutico , Nucleótidos/farmacología , Nucleótidos/uso terapéutico , Selección de Paciente , Guías de Práctica Clínica como Asunto , Seroconversión/efectos de los fármacos , Factores de Tiempo , Resultado del Tratamiento , Replicación Viral/efectos de los fármacos
16.
World J Gastroenterol ; 21(12): 3480-91, 2015 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-25834312

RESUMEN

Hepatitis C virus (HCV)-specific cytotoxic T cell (CTL) response plays a major role in viral control during spontaneous infection resolution. These cells develop an exhausted and pro-apoptotic status during chronic onset, being unable to get rid of HCV. The role of this response in contributing to sustained viral response (SVR) after anti-HCV is controversial. Recent studies show that after successful interferon-based anti-HCV treatment, HCV traces are still detectable and this correlates with a peak of HCV-specific CTL response activation, probably responsible for maintaining SVR by subsequent complete HCV clearing. Moreover, SVR patients' serum is still able to induce HCV infection in naïve chimpanzees, suggesting that the infection could be under the control of the immune system after a successful treatment, being transmissible in absence of this adaptive response. At least theoretically, treatment-induced viral load decrease could allow an effective HCV-specific CTL response reestablishment. This effect has been recently described with anti-HCV interferon-free regimes, based on direct-acting antivirals. Nevertheless, this is to some extent controversial with interferon-based therapies, due to the detrimental immunoregulatory α-interferon effect on T cells. Moreover, HCV-specific CTL response features during anti-HCV treatment could be a predictive factor of SVR that could have clinical implications in patient management. In this review, the recent knowledge about the role of HCV-specific CTL response in the development of SVR after anti-HCV treatment is discussed.


Asunto(s)
Antivirales/uso terapéutico , Hepacivirus/efectos de los fármacos , Hepatitis C Crónica/tratamiento farmacológico , Interferones/uso terapéutico , Activación de Linfocitos/efectos de los fármacos , Linfocitos T Citotóxicos/efectos de los fármacos , Animales , Hepacivirus/inmunología , Hepatitis C Crónica/inmunología , Hepatitis C Crónica/virología , Humanos , Linfocitos T Citotóxicos/inmunología , Linfocitos T Citotóxicos/virología , Factores de Tiempo , Resultado del Tratamiento , Carga Viral
17.
AJNR Am J Neuroradiol ; 24(5): 968-70, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12748104

RESUMEN

We report a case of a 65-year-old man who was admitted to the hospital on an emergent basis because of head trauma. Non-contrast-enhanced CT findings of the brain suggested a small extraaxial hematoma that was shown to be a superficial middle cerebral vein variant on subsequent MR images.


Asunto(s)
Venas Cerebrales/anomalías , Imagen por Resonancia Magnética , Trombosis del Seno Sagital/diagnóstico , Anciano , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Diagnóstico Diferencial , Traumatismos Cerrados de la Cabeza/complicaciones , Traumatismos Cerrados de la Cabeza/diagnóstico por imagen , Hematoma Epidural Craneal/diagnóstico , Humanos , Masculino , Trombosis del Seno Sagital/etiología , Tomografía Computarizada por Rayos X
18.
World J Gastroenterol ; 20(13): 3418-30, 2014 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-24707125

RESUMEN

Hepatitis C virus (HCV) infection affects about 170 million people worldwide and it is a major cause of liver cirrhosis and hepatocellular carcinoma. HCV is a hepatotropic non-cytopathic virus able to persist in a great percentage of infected hosts due to its ability to escape from the immune control. Liver damage and disease progression during HCV infection are driven by both viral and host factors. Specifically, adaptive immune response carries out an essential task in controlling non-cytopathic viruses because of its ability to recognize infected cells and to destroy them by cytopathic mechanisms and to eliminate the virus by non-cytolytic machinery. HCV is able to impair this response by several means such as developing escape mutations in neutralizing antibodies and in T cell receptor viral epitope recognition sites and inducing HCV-specific cytotoxic T cell anergy and deletion. To impair HCV-specific T cell reactivity, HCV affects effector T cell regulation by modulating T helper and Treg response and by impairing the balance between positive and negative co-stimulatory molecules and between pro- and anti-apoptotic proteins. In this review, the role of adaptive immune response in controlling HCV infection and the HCV mechanisms to evade this response are reviewed.


Asunto(s)
Inmunidad Adaptativa , Hepatitis C/inmunología , Anticuerpos/inmunología , Apoptosis , Linfocitos T CD4-Positivos/citología , Linfocitos T CD8-positivos/citología , Separación Celular , Quimiocinas/metabolismo , Epítopos/inmunología , Citometría de Flujo , Eliminación de Gen , Humanos , Inmunidad Celular , Inmunidad Humoral , Inflamación , Mutación , Fenotipo
19.
World J Gastroenterol ; 19(12): 1877-89, 2013 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-23569333

RESUMEN

Virus-specific T cells play an important role in the resolution of hepatic infection. However, during chronic hepatitis infection these cells lack their effector functions and fail to control the virus. Hepatitis B virus and hepatitis C virus have developed several mechanisms to generate immune tolerance. One of these strategies is the depletion of virus-specific T cells by apoptosis. The immunotolerogenic liver has unique property to retain and activate naïve T cell to avoid the over reactivation of immune response against antigens which is exploited by hepatotropic viruses to persist. The deletion of the virus-specific T cells occurs by intrinsic (passive) apoptotic mechanism. The pro-apoptotic molecule Bcl-2 interacting mediator (Bim) has attracted increasing attention as a pivotal involvement in apoptosis, as a regulator of tissue homeostasis and an enhancer for the viral persistence. Here, we reviewed our current knowledge on the evidence showing critical role of Bim in viral-specific T cell death by apoptotic pathways and helps in the immune tolerance.


Asunto(s)
Hepatitis Viral Humana/inmunología , Tolerancia Inmunológica , Linfocitos T/patología , Apoptosis/fisiología , Proteínas Reguladoras de la Apoptosis/fisiología , Proteína 11 Similar a Bcl2 , Muerte Celular/inmunología , Hepatitis Viral Humana/metabolismo , Humanos , Hígado/inmunología , Hígado/patología , Proteínas de la Membrana/fisiología , Proteínas Proto-Oncogénicas/fisiología
20.
Rev. esp. enferm. dig ; 108(10): 680-683, oct. 2016. tab, ilus
Artículo en Español | IBECS (España) | ID: ibc-156757

RESUMEN

El intervencionismo guiado por ecoendoscopia es un campo que se encuentra en rápido desarrollo. Recientemente se ha diseñado un nuevo prototipo de ecoendoscopio de visión frontal que pretende superar ciertas limitaciones de los ecoendoscopios convencionales (de visión oblicua). Se presenta a continuación el caso de un drenaje de pseudoquiste pancreático con un encoendoscopio de visión frontal llevado a cabo de forma exitosa. Si bien la difusión de este nuevo modelo de ecoendoscopio es aún escasa, las particularidades del mismo podrían contribuir a la ejecución con mayor sencillez de procedimientos terapéuticos habituales en la práctica clínica, así como a la consolidación de las potenciales aplicaciones del intervencionismo endoscópico (AU)


Interventional endoscopy is a field that continues to grow rapidly. A novel prototype forward-viewing echoendoscope (FV-EUS) has been recently developed in an attempt to overcome some of the limitations of conventional curved linear-array echoendoscopes (OV-EUS). We present a case of a successful endoscopic ultrasound-guided drainage of a pancreatic pseudocyst using a forward-viewing echoendoscope. Although the utilization use of this newly developed echoendoscope has not yet become widespread, its unique characteristics can help to easily perform routine therapeutic procedures and contribute to the expansion of interventional endoscopic utrasoundultrasound (AU)


Asunto(s)
Humanos , Femenino , Adulto , Seudoquiste Pancreático/cirugía , Endosonografía/métodos , Drenaje/métodos , Complicaciones Posoperatorias , Dehiscencia de la Herida Operatoria/cirugía , Fístula Pancreática/cirugía
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