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1.
Vaccines (Basel) ; 12(5)2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38793744

RESUMEN

Since the beginning of the COVID-19 pandemic, different viral vector-based and mRNA vaccines directed against the SARS-CoV-2 "S" spike glycoprotein have been developed and have shown a good profile in terms of safety and efficacy. Nevertheless, an unbiased comparison of vaccination efficiency, including post-vaccination neutralizing activity, between the different vaccines remains largely unavailable. This study aimed to compare the efficacy of one mRNA (BNT162b2) and two non-replicating adenoviral vector vaccines (ChAdOx1 nCoV-19 and Sputnik V) in a cohort of 1120 vaccinated Palestinian individuals who received vaccines on an availability basis and which displayed a unique diversity of genetic characteristics. We assessed the level of anti-S antibodies and further determined the antibody neutralizing activity in 261 of those individuals vaccinated with BNT162b2a (121), ChAdOx1 (72) or Sputnik V (68). Our results showed no significant difference in the distribution of serum-neutralizing activity or S-antibody serum levels for the three groups of vaccines, proving equivalence in efficacy for the three vaccines under real-life conditions. In addition, none of the eight demographic parameters tested had an influence on vaccination efficacy. Regardless of the vaccine type, the vaccination campaign ultimately played a pivotal role in significantly reducing the morbidity and mortality associated with COVID-19 in Palestine.

2.
PLoS Pathog ; 18(7): e1010736, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35857795

RESUMEN

Intracellular pathogens cause membrane distortion and damage as they enter host cells. Cells perceive these membrane alterations as danger signals and respond by activating autophagy. This response has primarily been studied during bacterial invasion, and only rarely in viral infections. Here, we investigate the cellular response to membrane damage during adenoviral entry. Adenoviruses and their vector derivatives, that are an important vaccine platform against SARS-CoV-2, enter the host cell by endocytosis followed by lysis of the endosomal membrane. We previously showed that cells mount a locally confined autophagy response at the site of endosomal membrane lysis. Here we describe the mechanism of autophagy induction: endosomal membrane damage activates the kinase TBK1 that accumulates in its phosphorylated form at the penetration site. Activation and recruitment of TBK1 require detection of membrane damage by galectin 8 but occur independently of classical autophagy receptors or functional autophagy. Instead, TBK1 itself promotes subsequent autophagy that adenoviruses need to take control of. Deletion of TBK1 reduces LC3 lipidation during adenovirus infection and restores the infectivity of an adenovirus mutant that is restricted by autophagy. By comparing adenovirus-induced membrane damage to sterile lysosomal damage, we implicate TBK1 in the response to a broader range of types of membrane damage. Our study thus highlights an important role for TBK1 in the cellular response to adenoviral endosome penetration and places TBK1 early in the pathway leading to autophagy in response to membrane damage.


Asunto(s)
Infecciones por Adenoviridae , Autofagia , Endosomas , Proteínas Serina-Treonina Quinasas , Adenoviridae/metabolismo , Infecciones por Adenoviridae/metabolismo , Endosomas/metabolismo , Galectinas/metabolismo , Humanos , Proteínas Serina-Treonina Quinasas/genética
3.
Proc Natl Acad Sci U S A ; 119(28): e2202370119, 2022 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-35749382

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections initiate in the bronchi of the upper respiratory tract and are able to disseminate to the lower respiratory tract, where infections can cause an acute respiratory distress syndrome with a high degree of mortality in elderly patients. We used reconstituted primary bronchial epithelia from adult and child donors to follow the SARS-CoV-2 infection dynamics. We show that, in epithelia from adult donors, infections initiate in multiciliated cells and spread within 24 to 48 h throughout the whole epithelia. Syncytia formed of ciliated and basal cells appeared at the apical side of the epithelia within 3 to 4 d and were released into the apical lumen, where they contributed to the transmittable virus dose. A small number of reconstituted epithelia were intrinsically more resistant to virus infection, limiting virus spread to different degrees. This phenotype was more frequent in epithelia derived from children versus adults and correlated with an accelerated release of type III interferon. Treatment of permissive adult epithelia with exogenous type III interferon restricted infection, while type III interferon gene knockout promoted infection. Furthermore, a transcript analysis revealed that the inflammatory response was specifically attenuated in children. Taken together, our findings suggest that apical syncytia formation is an underappreciated source of virus propagation for tissue or environmental dissemination, whereas a robust type III interferon response such as commonly seen in young donors restricted SARS-CoV-2 infection. Thus, the combination of interferon restriction and attenuated inflammatory response in children might explain the epidemiological observation of age-related susceptibility to COVID-19.


Asunto(s)
Bronquios , COVID-19 , Células Gigantes , Interferones , Mucosa Respiratoria , SARS-CoV-2 , Anciano , Bronquios/inmunología , Bronquios/virología , COVID-19/inmunología , COVID-19/virología , Niño , Susceptibilidad a Enfermedades , Células Gigantes/inmunología , Células Gigantes/virología , Humanos , Interferones/inmunología , Mucosa Respiratoria/inmunología , Mucosa Respiratoria/virología , SARS-CoV-2/inmunología , Interferón lambda
4.
PLoS Pathog ; 13(2): e1006217, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28192531

RESUMEN

Cells employ active measures to restrict infection by pathogens, even prior to responses from the innate and humoral immune defenses. In this context selective autophagy is activated upon pathogen induced membrane rupture to sequester and deliver membrane fragments and their pathogen contents for lysosomal degradation. Adenoviruses, which breach the endosome upon entry, escape this fate by penetrating into the cytosol prior to autophagosome sequestration of the ruptured endosome. We show that virus induced membrane damage is recognized through Galectin-8 and sequesters the autophagy receptors NDP52 and p62. We further show that a conserved PPxY motif in the viral membrane lytic protein VI is critical for efficient viral evasion of autophagic sequestration after endosomal lysis. Comparing the wildtype with a PPxY-mutant virus we show that depletion of Galectin-8 or suppression of autophagy in ATG5-/- MEFs rescues infectivity of the PPxY-mutant virus while depletion of the autophagy receptors NDP52, p62 has only minor effects. Furthermore we show that wildtype viruses exploit the autophagic machinery for efficient nuclear genome delivery and control autophagosome formation via the cellular ubiquitin ligase Nedd4.2 resulting in reduced antigenic presentation. Our data thus demonstrate that a short PPxY-peptide motif in the adenoviral capsid permits multi-layered viral control of autophagic processes during entry.


Asunto(s)
Infecciones por Adenovirus Humanos/metabolismo , Autofagia/fisiología , Proteínas de la Cápside/metabolismo , Galectinas/metabolismo , Internalización del Virus , Adenoviridae , Infecciones por Adenovirus Humanos/inmunología , Secuencias de Aminoácidos , Animales , Western Blotting , Línea Celular , Ensayo de Inmunoadsorción Enzimática , Ensayo de Immunospot Ligado a Enzimas , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Humanos , Procesamiento de Imagen Asistido por Computador , Ratones , Microscopía Confocal , Microscopía Electrónica de Transmisión
5.
AIDS Res Hum Retroviruses ; 23(2): 335-40, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17331042

RESUMEN

We present here the first data available on resistance to nucleoside reverse transcriptase inhibitors (NRTIs) and nonnucleoside reverse transcriptase inhibitors (NNRTIs) in India. In these subtype C isolates, we have observed most of the mutations noted in reverse transcriptase (RT) for subtype B with some additional substitutions (at positions 98, 203, 208, and 221) that will warrant attention in the algorithms used.


Asunto(s)
Terapia Antirretroviral Altamente Activa , Farmacorresistencia Viral/genética , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , ADN Polimerasa Dirigida por ARN/genética , Inhibidores de la Transcriptasa Inversa/farmacología , Infecciones por VIH/genética , VIH-1/clasificación , VIH-1/genética , Humanos , India , Mutación/genética , Polimorfismo Genético/genética , Insuficiencia del Tratamiento
6.
Gastroenterol Clin Biol ; 31(12): 1088-94, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18176363

RESUMEN

OBJECTIVE: To determine the prevalence of HBV genotypes in Southwestern France and the association between HBV genotypes and patients characteristics. METHODS: 194 HBsAg-positive patients (median age: 45 yrs, range: 7-77, male: 78%) followed in Bordeaux Hospital in 1999-2004 were included. HBV genotype, pre-core (PC) and core promoter (CP) mutations were determined by sequencing. RESULTS: Genotype distribution was A 51%, B 6.7%, C 5.7%, D 26.3%, E 7.7%, F 0.5%, G 2.1%. Among the 146 patients documented, 71.2% were Caucasians, 15.8% Africans, 13.0% Asians. Fifty-seven patients (36%) were HIV-infected. Eighty-two (42.3%) patients were HBeAg-positive. Genotype A was almost exclusively carried by Caucasians (96%), Africans were most frequent among genotype E (82%), and Asians were most prevalent among genotypes B and C (82% and 80%, respectively). Genotype A was associated with a higher prevalence of HBeAg than genotype D (53% versus 35.3%, P=0.03). PC variant was detected in 35% and CP variant in 43% of patients. PC variant was uncommon in genotype A patients (7.3%). CONCLUSION: Distribution of HBV genotypes differs according to ethnic origin, genotypes A and D being the most frequently found. Genotype A was more frequently associated with HBeAg-positivity and genotype D with HBeAg-negativity.


Asunto(s)
Virus de la Hepatitis B/genética , Hepatitis B/virología , Adolescente , Adulto , Anciano , Niño , Etnicidad/genética , Femenino , Francia , Variación Genética/genética , Genotipo , Infecciones por VIH/complicaciones , Hepatitis B/transmisión , Antígenos de Superficie de la Hepatitis B/análisis , Antígenos e de la Hepatitis B/análisis , Virus de la Hepatitis B/clasificación , Humanos , Masculino , Persona de Mediana Edad , Mutación/genética , Grupos Raciales/genética , Estudios Retrospectivos , Proteínas del Núcleo Viral/genética
7.
J Hepatol ; 46(1): 19-25, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17030451

RESUMEN

BACKGROUND/AIMS: The aim of this study was to describe the natural history of a HCV infection outbreak in 196 patients who had sclerotherapy by a same physician and to confirm patient-to-patient transmission using phylogenetic analysis in a large series of patients. METHODS: Demographic information included clinical and biological parameters. Fibrosis evaluation was performed using liver biopsy or transient elastography. Follow-up was maintained until death, or the end of the observation period. In order to determine if the virus had been transmitted between the HCV genotype 2 patients, sequence analysis was undertaken of a part of the NS5b region of the genomes in samples of patients. RESULTS: The mean duration of follow-up was 23.1+/-6.7 years (4535 patient-years). In patients with fibrosis evaluation, 55.7% had no or mild fibrosis and 44.3% had significant fibrosis. No patient died from HCV-related disease. Nucleotide sequence analysis of a part of the NS5b region revealed that patients were all infected with the same HCV subtype (genotype 2d). The most evident feature of the tree is the clustering of all patients involved in the outbreak without any unrelated isolates. CONCLUSION: This study emphasizes the risk for nosocomial spread of HCV during intravenous therapy.


Asunto(s)
Infección Hospitalaria/epidemiología , Infección Hospitalaria/transmisión , Brotes de Enfermedades , Hepatitis C/epidemiología , Hepatitis C/transmisión , Escleroterapia/efectos adversos , Várices/terapia , Adulto , Infección Hospitalaria/virología , Femenino , Estudios de Seguimiento , Francia/epidemiología , Genotipo , Hepacivirus/clasificación , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Hepatitis C/virología , Humanos , Masculino , Persona de Mediana Edad , Filogenia , Factores de Tiempo , Proteínas no Estructurales Virales/genética
8.
J Clin Microbiol ; 44(5): 1877-80, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16672429

RESUMEN

Liver and plasma hepatitis C virus (HCV) variability was compared by E2 cloning and sequencing in three patients coinfected with HCV and human immunodeficiency virus (HIV) before and after interferon treatment and in three patients solely infected with HCV. The plasma and liver samples contained unique sequences. In the patients coinfected with HIV, accumulated random mutations produced mostly nonsynonymous substitutions in contrast to the reduced HCV genetic variability seen after treatment.


Asunto(s)
Infecciones por VIH/complicaciones , Hepacivirus/genética , Hepatitis C/complicaciones , Hepatitis C/virología , Estudios de Casos y Controles , Variación Genética , Genotipo , Hepacivirus/aislamiento & purificación , Hepatitis C/tratamiento farmacológico , Humanos , Interferones/uso terapéutico , Hígado/virología , Especificidad de Órganos , Viremia/virología
9.
J Clin Virol ; 36(1): 36-42, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16513416

RESUMEN

OBJECTIVE: To assess the genotypic determinants of the virological response (VR) to didanosine (ddI) in nucleoside reverse transcriptase inhibitors (NRTI)-experienced patients. METHODS: Human immunodeficiency virus type 1 (HIV-1) genotype was determined at baseline in 74 ddI-naive-patients with baseline viral load >500 copies/ml and receiving ddI as part of a new regimen. VR was defined as a plasma HIV-1 RNA <50 copies/ml after three months on ddI. NRTI resistance mutations associated with higher or lower frequencies of VR with a p-value<0.25 were retained in different sets of mutations, where the mutations associated with a worse VR were added, whereas the mutations associated with a better VR were subtracted. The most significant mutation scores were then studied in a multivariate analysis. RESULTS: Changes at three codons (M41L, L210W, T215Y/F/D/C/E) were associated with a worse VR and three mutations (K70R, M184V, K219Q) with a better VR. The strongest association with the VR was obtained with the score M41L+L210W+T215Y/F/D/C/E-K70R-K219Q. The score was independently associated with the VR in the multivariate analysis. CONCLUSION: Taking into account the mutations associated with a better VR may improve genotypic resistance algorithms. Our results are of interest for the management of antiretroviral therapy in NRTI-experienced patients.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Didanosina/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , VIH-1/genética , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Algoritmos , Farmacorresistencia Viral , Genotipo , Infecciones por VIH/virología , Humanos , Análisis Multivariante , Mutación , ARN Viral/sangre , ARN Viral/genética , Estudios Retrospectivos , Factores de Tiempo , Carga Viral
10.
J Clin Virol ; 34(4): 288-94, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16286052

RESUMEN

BACKGROUND: Treatment interruption (TI) in antiretroviral-treated patients on virological failure (VF) often results in a shift from resistant to wild-type HIV-1 in plasma. A clonal analysis was set out to determine the importance of archiving of resistant HIV-1 variants during TI and its relationship with the occurrence of a VF after treatment resumption. METHODS: A fragment of the pol gene was cloned and sequenced from peripheral blood mononuclear cells DNA sampled at the end of TI. Clonal sequences were compared to bulk plasma sequences determined before TI, after TI and at VF. RESULTS: Four patients were enrolled; all had a complete reversion to wild-type HIV-1 at the end of TI. In two patients with subsequent VF, archiving of minority resistant variants was detected in proviral DNA. Archived resistant variants were found to be phylogenetically linked to sequences detected before TI and at VF, suggesting the re-expansion of resistant HIV-1 from archived quasi-species. CONCLUSION: In patients having a TI in the context of VF, archiving of resistant HIV-1 variants in proviral DNA can be involved into the mechanisms of further VF after treatment resumption.


Asunto(s)
ADN Viral/genética , Infecciones por VIH/virología , VIH-1/genética , Provirus/genética , Fármacos Anti-VIH/uso terapéutico , Terapia Antirretroviral Altamente Activa , Farmacorresistencia Viral , Infecciones por VIH/tratamiento farmacológico , Proteasa del VIH/genética , Transcriptasa Inversa del VIH/genética , Humanos , Leucocitos Mononucleares/virología , Mutación , Filogenia , Insuficiencia del Tratamiento , Resultado del Tratamiento , Carga Viral
11.
J Med Virol ; 76(2): 279-84, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15834864

RESUMEN

The aim of this study was to provide evidence for patient-to-patient nosocomial hepatitis C virus (HCV) transmission during sclerotherapy of varicose veins. Forty-three patients who had evidence of current infection by genotype 2 HCV have had sclerotherapy by the same physician. Based on this observation, a detailed epidemiological questionnaire on risk factors for HCV in genotype 2 infected patients was conducted. Seventeen sequences in the hypervariable region 1 (HVR1) of the HCV genome obtained from 17 HCV RNA positive patients with a past history of sclerotherapy, were compared with 17 sequences derived from genotype 2 patients with no past history of sclerotherapy, and with 25 sequences sampled from GenBank. Two hundred seven genotype 2 HCV infected patients were included. The main risk factors for HCV infection were transfusion (n = 76), drug use (n = 6), and sclerotherapy of varicose veins (n = 62 including 43 (20.8%) by the same physician), other or unknown (n = 76). These sclerotherapy sessions were carried out in the 1980s for many years. Five of these 43 patients had jaundice within a few weeks after a sclerotherapy session. Sequence analysis of HVR1 from 17 patients who had sclerotherapy by the same physician revealed that they were all infected with HCV genotype 2c. The phylogenetic tree indicated clustering of the patients with a past history of sclerotherapy. The method by which infection was likely to have been transmitted was probably the use of a single vial for multiple patients. This study provides strong evidence that sclerotherapy of varicose veins is a risk factor for HCV infection.


Asunto(s)
Infección Hospitalaria/transmisión , Hepacivirus/genética , Hepatitis C/transmisión , Escleroterapia/efectos adversos , Várices/complicaciones , Várices/terapia , Adolescente , Adulto , Anciano , Infección Hospitalaria/virología , ADN Complementario/química , ADN Viral/química , Femenino , Hepacivirus/clasificación , Hepacivirus/aislamiento & purificación , Hepatitis C/virología , Humanos , Pacientes Internos , Masculino , Persona de Mediana Edad , Filogenia , ARN Viral/genética , ARN Viral/aislamiento & purificación , Análisis de Secuencia de ADN , Homología de Secuencia
12.
AIDS Res Hum Retroviruses ; 20(9): 1032-5, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15585093

RESUMEN

The molecular characterization of HIV-1 isolates in drug-naive cases in the early stages of HIV disease was studied in 128 cases from Mumbai (Bombay), India. Subtype C was largely predominant followed by A-C intersubtype recombinants, one subtype A and one CRF01 AE. Compared to subtype B, subtype C exhibited an important polymorphism; the percentages of substitutions could reach more than 90%. Two isolates showed M184V substitution the reverse transcriptase indicating resistance to 3TC.


Asunto(s)
Farmacorresistencia Viral/genética , Infecciones por VIH/tratamiento farmacológico , VIH-1/clasificación , Mutación , Adulto , Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/virología , Proteasa del VIH/genética , Transcriptasa Inversa del VIH/genética , VIH-1/enzimología , VIH-1/genética , Humanos , India , Datos de Secuencia Molecular , Análisis de Secuencia de ADN
14.
AIDS Res Hum Retroviruses ; 19(1): 41-7, 2003 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-12596719

RESUMEN

Non-B HIV-1 samples collected in France between 1999 and 2001 were sequenced in the env, reverse transcriptase (RT), and protease genes (1) to characterize further the non-B strains circulating in the country, (2) to assess the importance of recombination, and (3) to describe the polymorphism of RT and protease genes and appreciate a possible impact on susceptibility to antiretroviral (ARV) drugs. The results show that, within a background of CRF02_AG predominance, there is a high genetic diversity of non-B isolates, including intersubtype recombinants. There is an extensive polymorphism of protease and RT genes compared with B consensus sequences; we have so far no data indicating that these non-B isolates may have reduced sensitivity to ARV drugs.


Asunto(s)
Fármacos Anti-VIH/farmacología , Genes env/genética , Variación Genética , Infecciones por VIH/virología , Proteasa del VIH/genética , Transcriptasa Inversa del VIH/genética , VIH-1/efectos de los fármacos , VIH-1/genética , Adulto , Sustitución de Aminoácidos , Fármacos Anti-VIH/uso terapéutico , Farmacorresistencia Viral , Femenino , Francia , Infecciones por VIH/tratamiento farmacológico , Proteasa del VIH/química , Transcriptasa Inversa del VIH/química , VIH-1/clasificación , Humanos , Masculino , Persona de Mediana Edad , Recombinación Genética , Inhibidores de la Transcriptasa Inversa/farmacología , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Análisis de Secuencia de ADN
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