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result(s) for
"Sauleda, Silvia"
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Effect of Hepatitis E Virus RNA Universal Blood Donor Screening, Catalonia, Spain, 2017‒2020
2022
Hepatitis E virus (HEV) is the major cause of acute viral hepatitis in several countries in Europe. HEV is acquired mainly by consumption of contaminated pork but can also be transmitted through blood transfusion. HEV infection is usually self-limited but can become persistent in immunocompromised persons. During the first 30 months of HEV RNA universal screening of blood donations in Catalonia, Spain, we identified 151 HEV RNA-positive donations (1/4,341 blood donations). Most infected donors reported consumption of pates and sausages, and 58% were negative for HEV IgM and IgG. All HEV isolates belonged to genotype 3. All infected donors spontaneously resolved the infection, and no neurologic symptoms and reinfections were observed after 1 year of follow-up. Since the implementation of HEV RNA universal screening, no new cases of transfusion-transmitted HEV infection were reported. Our data indicate HEV screening of blood donations provides safer blood for all recipients, especially for immunosuppressed persons.
Journal Article
More DNA and RNA of HBV SP1 splice variants are detected in genotypes B and C at low viral replication
2021
HBV produces unspliced and spliced RNAs during replication. Encapsidated spliced RNA is converted into DNA generating defective virions that are detected in plasma and associated with HCC development. Herein we describe a quantitative real-time PCR detection of splice variant SP1 DNA/RNA in HBV plasma. Three PCR primers/probe sets were designed detecting the SP1 variants, unspliced core, or X gene. Plasmids carrying the three regions were constructed for the nine HBV genotypes to evaluate the three sets, which were also tested on DNA/RNA extracted from 193 HBV plasma with unknown HCC status. The assay had an LOD of 80 copies/ml and was equally efficient for detecting all nine genotypes and three targets. In testing 84 specimens for both SP1 DNA (77.4%) and RNA (82.1%), higher viral loads resulted in increased SP1 levels. Most samples yielded < 1% of SP1 DNA, while the average SP1 RNA was 3.29%. At viral load of ≤ 5 log copies/ml, the detectable SP1 DNA varied by genotype, with 70% for B, 33.3% for C, 10.5% for E, 4% for D and 0% for A, suggesting higher levels of splicing in B and C during low replication. At > 5 log, all samples regardless of genotype had detectable SP1 DNA.
Journal Article
Partial restoration of immune response in Hepatitis C patients after viral clearance by direct-acting antiviral therapy
by
Llorens-Revull, Meritxell
,
Bes, Marta
,
Riveiro-Barciela, Mar
in
Adult
,
Aged
,
Antiviral agents
2021
HCV CD4+ and CD8+ specific T cells responses are functionally impaired during chronic hepatitis C infection. DAAs therapies eradicate HCV infection in more than 95% of treated patients. However, the impact of HCV elimination on immune responses remain controversial. Here, we aimed to investigate whether HCV cure by DAAs could reverse the impaired immune response to HCV.
We analyzed 27 chronic HCV infected patients undergoing DAA treatment in tertiary care hospital, and we determined the phenotypical and functional changes in both HCV CD8+ and CD4+ specific T-cells before and after viral clearance. PD-1, TIM-3 and LAG-3 cell-surface expression was assessed by flow cytometry to determine CD4+ T cell exhaustion. Functional responses to HCV were analyzed by IFN-Ɣ ELISPOT, intracellular cytokine staining (IL-2 and IFN-Ɣ) and CFSE-based proliferation assays.
We observed a significant decrease in the expression of PD-1 in CD4+ T-cells after 12 weeks of viral clearance in non-cirrhotic patients (p = 0.033) and in treatment-naive patients (p = 0.010), indicating a partial CD4 phenotype restoration. IFN-Ɣ and IL-2 cytokines production by HCV-specific CD4+ and CD8+ T cells remained impaired upon HCV eradication. Finally, a significant increase of the proliferation capacity of both HCV CD4+ and CD8+ specific T-cells was observed after HCV elimination by DAAs therapies.
Our results show that in chronically infected patients HCV elimination by DAA treatment lead to partial reversion of CD4+ T cell exhaustion. Moreover, proliferative capacity of HCV-specific CD4+ and CD8+ T cells is recovered after DAA's therapies.
Journal Article
Molecular and Serological Characterization of Hepatitis B Virus (HBV)-Positive Samples with Very Low or Undetectable Levels of HBV Surface Antigen
2021
Background: Gaps remain in the detection of nucleic acid test (NAT) yield and occult hepatitis B virus (HBV) infection (OBI) by current HBV surface antigen (HBsAg) assays. The lack of detection may be due to HBsAg levels below current assay detection limits, mutations affecting HBsAg assays or HBsAg levels, or the masking of HBsAg by antibody to HBsAg (anti-HBs). In this study, we evaluate the incremental detection of NAT yield and OBI from five diverse geographic areas by an improved sensitivity HBsAg assay and characterize the samples relative to the viral load, anti-HBs status, and PreS1–S2–S mutations. Included is a comparison population with HBV DNA levels comparable to OBI, but with readily detectable HBsAg (High Surface–Low DNA, HSLD). Methods: A total of 347 samples collected from the USA, South Africa, Spain, Cameroon, Vietnam, and Cote D’Ivoire representing NAT yield (HBsAg(−), antibody to HBV core antigen (anti-HBc)(−), HBV DNA(+), N = 131), OBI (HBsAg(−), anti-HBc(+), HBV DNA(+), N = 188), and HSLD (HBsAg(+), anti-HBc(+), HBV DNA(+), N = 28) were tested with ARCHITECT HBsAg NEXT (HBsAgNx) (sensitivity 0.005 IU/mL). The sequencing of the PreS1–S2–S genes from a subset of 177 samples was performed to determine the genotype and assess amino acid variability, particularly in anti-HBs(+) samples. Results: HBsAgNx detected 44/131 (33.6%) NAT yield and 42/188 (22.3%) OBI samples. Mean HBV DNA levels for NAT yield and OBI samples were lower in HBsAgNx(−) (50.3 and 25.9 IU/mL) than in HBsAgNx(+) samples (384.1 and 139.5 IU/mL). Anti-HBs ≥ 10 mIU/mL was present in 28.6% HBsAgNx(+) and 45.2% HBsAgNx(−) OBI, and in 3.6% HSLD samples. The genotypes were A1, A2, B, C, D, E, F, and H. There was no significant difference between HBsAgNx(−) and HBsAgNx(+) in the proportion of samples harboring substitutions or in the mean number of substitutions per sample in PreS1, PreS2, or S for the NAT yield or OBI (p range: 0.1231 to >0.9999). A total of 21/27 (77.8%) of HBsAgNx(+) OBI carried S escape mutations, insertions, or stop codons. HSLD had more PreS1 and fewer S substitutions compared to both HBsAgNx(−) and HBsAgNx(+) OBI. Mutations/deletions associated with impaired HBsAg secretion were observed in the OBI group. Conclusions: HBsAgNx provides the improved detection of NAT yield and OBI samples. Samples that remain undetected by HBsAgNx have exceptionally low HBsAg levels below the assay detection limit, likely due to low viremia or the suppression of HBsAg expression by host and viral factors.
Journal Article
Advanced molecular surveillance approaches for characterization of blood borne hepatitis viruses
by
Olivo, Ana
,
Gozlan, Yael
,
Rodgers, Mary A.
in
Biology and Life Sciences
,
Blood
,
Blood & organ donations
2020
Defining genetic diversity of viral infections directly from patient specimens is the ultimate goal of surveillance. Simple tools that can provide full-length sequence information on blood borne viral hepatitis viruses: hepatitis C, hepatitis B and hepatitis D viruses (HCV, HBV and HDV) remain elusive. Here, an unbiased metagenomic next generation sequencing approach (mNGS) was used for molecular characterization of HCV infections (n = 99) from Israel which yielded full-length HCV sequences in 89% of samples, with 7 partial sequences sufficient for classification. HCV genotypes were primarily 1b (68%) and 1a (19%), with minor representation of genotypes 2c (1%) and 3a (8%). HBV/HDV coinfections were characterized by suppressed HBV viral loads, resulting in sparse mNGS coverage. A probe-based enrichment approach (xGen) aiming to increase HBV and HDV coverage was validated on a panel of diverse genotypes, geography and titers. The method extended HBV genome coverage a median 61% (range 8-84%) and provided orders of magnitude boosts in reads and sequence depth for both viruses. When HBV-xGen was applied to Israeli samples, coverage was improved by 28-73% in 4 samples and identified HBV genotype A1, A2, D1 specimens and a dual B/D infection. Abundant HDV reads in mNGS libraries yielded 18/26 (69%) full genomes and 8 partial sequences, with HDV-xGen only providing minimal extension (3-11%) of what were all genotype 1 genomes. Advanced molecular approaches coupled to virus-specific capture probes promise to enhance surveillance of viral infections and aid in monitoring the spread of local subtypes.
Journal Article
HTLV-1/2 Infection in Blood Donors from a Non-Endemic Area (Catalonia, Spain) between 2008 and 2017: A 10-Year Experience
2022
Human T-cell lymphotropic virus type 1 and 2 (HTLV-1/2) screening is not mandatory in Spanish blood banks. In Catalonia, selective screening was introduced in 2008, followed by universal screening in 2011. We present herein a 10-year experience of HTLV testing in blood donors. HTLV-1/2 selective screening was performed using Ortho-Clinical Diagnostics HTLV-I/HTLV-II Ab-Capture ELISA between February 2008 and May 2009, then Abbott Prism HTLV-I/ HTLV-II assay until December 2010. Abbott Architect rHTLV-I/II assay was then used for HTLV-1/2 universal screening in pooled samples. INNO-LIA HTLV I/II Score (Fujirebio) and in-house HTLV-1/2 proviral DNA real-time PCR were used in reactive samples. Follow-up was offered to confirm HTLV-1/2 donors in Vall d’Hebron Hospital. Between 2008 and 2017, 51 blood donors were confirmed HTLV positive (46 HTLV-1, 4 HTLV-2 and 1 HTLV) out of 2,114,891 blood donations (1 in 41,468). Sixty-nine percent were female, median age was 40 years and most were born in Latin America (69%), followed by Europe (25%), Africa (4%) and Asia (2%). Screening of relatives and partners identified 12 additional HTLV-1 cases. Lookback studies did not show any HTLV-1/2 transmission. HTLV infections found in blood donors mirror epidemiological changes in the population of Spain. Consequently, HTLV should be considered a potential risk for recipients and calls for the design of optimal strategies to ensure transfusion safety.
Journal Article
Evaluation of occult hepatitis B infection in tissue donors: a multicenter analysis in Spain
by
Rafael Villalba Montoro
,
Lopez, Marta Pevida
,
Teresa Seoane Pillado
in
Antigens
,
Core protein
,
Deoxyribonucleic acid
2019
Traditionally, when antibody to the Hepatitis B core antigen (anti-HBc) and antibody to the Hepatitis B surface antigen (anti-HBs) are positive, the donor is considered suitable. However, the literature contains cases with this profile and circulating hepatitis B virus DNA. The aim of the study is to analyze the incidence of occult hepatitis B virus infection (OBI). Retrospective data were evaluated for deceased tissue donors in ten Tissue Establishments (Spain) during 2017. The data included demographic data and the serological markers for hepatitis B that each tissue establishment performed. A total number of 1933 tissue donors were evaluated. A total of 180 donors were excluded: 6 (0.3%) with Hepatitis B surface antigen (HBs positive), and 174 in which DNA testing was not performed. Anti-HBc was positive in 175 donors (10%), in which anti-HBs was negative in 30 (17.1%) and positive in 145 (82.9%). In total, 27 donors with DNA positive (1.5%) were found, of which 3 of 117 donors (1.7%) showed anti-HBc negative and anti-HBs positive (> 10 IU/ml), 4 of 30 donors (13.3%) showed anti-HBc positive and anti-HBs negative and 20 of 145 donors (13.8%) showed both anti-HBc and anti-HBs positive. The highest probability of finding DNA occurs when anti-HBc is positive, regardless of the presence of anti-HBs. In our study, the probability of OBI was 1.5%. The classic concept that when anti-HBc and anti-HBs are positive (even with a titer of over 100 IU/ml) the donor can be accepted should, therefore, be reconsidered, and DNA testing should be mandatory.
Journal Article
Comparison of Extracellular Vesicle Isolation Methods for miRNA Sequencing
by
Llorens-Revull, Meritxell
,
Burgui, Idoia
,
Corrales, Irene
in
Analysis
,
Biomarkers
,
Cholesterol
2023
MicroRNAs (miRNAs) encapsulated in extracellular vesicles (EVs) are potential diagnostic and prognostic biomarkers. However, discrepancies in miRNA patterns and their validation are still frequent due to differences in sample origin, EV isolation, and miRNA sequencing methods. The aim of the present study is to find a reliable EV isolation method for miRNA sequencing, adequate for clinical application. To this aim, two comparative studies were performed in parallel with the same human plasma sample: (i) isolation and characterization of EVs obtained using three procedures: size exclusion chromatography (SEC), iodixanol gradient (GRAD), and its combination (SEC+GRAD) and (ii) evaluation of the yield of miRNA sequences obtained using NextSeq 500 (Illumina) and three miRNA library preparation protocols: NEBNext, NEXTFlex, and SMARTer smRNA-seq. The conclusion of comparison (i) is that recovery of the largest amount of EVs and reproducibility were attained with SEC, but GRAD and SEC+GRAD yielded purer EV preparations. The conclusion of (ii) is that the NEBNext library showed the highest reproducibility in the number of miRNAs recovered and the highest diversity of miRNAs. These results render the combination of GRAD EV isolation and NEBNext library preparation for miRNA retrieval as adequate for clinical applications using plasma samples.
Journal Article
Doubtful Role of IL28B Polymorphism in Occult Hepatitis B Infection
by
Piron, Maria
,
Puig, Lluís
,
Vargas, Victor
in
Adult
,
Blood Donors
,
Enzyme-Linked Immunospot Assay
2015
Aims: To investigate the influence of IL28B polymorphism in occult hepatitis B infection (OBI) and whether IL28B genetic variants are associated with hepatitis B virus (HBV)-specific T-cell responses. Patients and Methods: The rs12979860 IL28B genotype was determined in 34 OBI blood donors, 22 spontaneous HBV resolvers, 36 inactive HBV carriers and 25 seronegative donors. T-cell responses to HBV recombinant proteins were assessed by interferon-γ enzyme-linked immunospot assay. Results: The frequency of the IL28B CC genotype among OBI patients was similar to that of inactive carriers [41 vs. 39%, respectively, p = 0.961; odds ratio (OR) = 1.10; 95% confidence interval (CI) = 0.42-2.86; p = 0.845]. The IL28B CC genotype was found more frequently in spontaneous resolvers, although the differences were not significant (45 vs. 39%, spontaneous resolvers and inactive carriers, respectively; p = 0.828; OR = 1.31; 95% CI = 0.45-3.83; p = 0.622). HBV-specific T-cell responses were detected in OBIs, and significantly stronger T-cell responses towards hepatitis B envelope antigen were observed in those with the IL28B CC genotype. In spontaneous resolvers and inactive carriers, IL28B CC did not correlate with the magnitude of T-cell responses. Conclusions: In OBI donors, IL28B CC correlates with the intensity of HBV-specific T-cell responses. In this study, IL28B CC is not statistically associated with OBI or with HBV clearance, but a larger number of cases is needed before completely ruling out its role in HBV infection.
Journal Article
Extracellular vesicle isolation and characterization in the follow up of HCV-infected patients treated with directly-acting antiviral agents (DAAs)
2018
Background: Extracellular vesicles (EVs) are present in human biofluids and as such, they can potentially serve as a source of novel biomarkers in disease diagnosis such as cancer or infectious diseases. Exosomes are a type of EVs, with a lipid bilayer, that carries a broad repertoire of cellular components. Exosome content generally reflects the nature and status of the cell of origin. The aim of this preliminary study is to explore the most suitable method for exosome isolation to characterize and study the exosome content as a diagnostic tool for liver diseases. Methods: Exosomes were isolated by an affinity-based method (WAKO kit) which uses T-cell immunoglobulin domain and mucin domaincontaining protein 4 (Tim4). Isolated EVs were quantified and visualized by the nanosight NS300 and transmission electron microscopy (TEM), respectively. CD63, CD9, HSP70 and CD81 proteins were quantified by western blot. The total RNA was extracted by miRNeasy Mini Kit (Qiagen), and the microRNA (miRNA) integrity was measured by the RNA 6000 Pico mRNA (Agilent Technologies) using Bioanalyzer 2100. Results: The technique was able to reproducibly obtain 109 EVs/ml of serum as quantified by nanosight tracking analysis in both fresh and frozen samples. The preparation showed close-to-spherical shape particles of50-150 nm, according to TEM analysis. At present, only the CD63 protein has been identified by western blot, therefore additional tests are needed for EV characterization. Around 100 pg/pl of total RNA was obtained from the samples. Summary/Conclusion: Exosome isolation using magnetic beads is optimal in order to obtain a highly pure EV preparation. Improvements in extraction methodology are ongoing.
Journal Article