Humoral Immunity across the SARS-CoV-2 Spike after Sputnik V (Gam-COVID-Vac) Vaccination.

SARS-CoV-2 vaccines have contributed to attenuating the burden of the COVID-19 pandemic by promoting the development of effective immune responses, thus reducing the spread and severity of the pandemic. A clinical trial with the Sputnik-V vaccine was conducted in Venezuela from December 2020 to July 2021. The aim of this study was to explore the antibody reactivity of vaccinated individuals towards different regions of the spike protein (S). Neutralizing antibody (NAb) activity was assessed using a commercial surrogate assay, detecting NAbs against the receptor-binding domain (RBD), and a plaque reduction neutralization test. NAb levels were correlated with the reactivity of the antibodies to the spike regions over time. The presence of Abs against nucleoprotein was also determined to rule out the effect of exposure to the virus during the clinical trial in the serological response. A high serological reactivity was observed to S and specifically to S1 and the RBD. S2, although recognized with lower intensity by vaccinated individuals, was the subunit exhibiting the highest cross-reactivity in prepandemic sera. This study is in agreement with the high efficacy reported for the Sputnik V vaccine and shows that this vaccine is able to induce an immunity lasting for at least 180 days. The dissection of the Ab reactivity to different regions of S allowed us to identify the relevance of epitopes outside the RBD that are able to induce NAbs. This research may contribute to the understanding of vaccine immunity against SARS-CoV-2, which could contribute to the design of future vaccine strategies.

Neutralization of Different Variants of SARS-CoV-2 by a F(ab')2 Preparation from Sera of Horses Immunized with the Viral Receptor Binding Domain.

The Receptor Binding Domain (RBD) of SARS-CoV-2, the virus responsible for the COVID-19 pandemic, is the functional region of the viral Spike protein (S), which is involved in cell attachment to target cells. The virus has accumulated progressively mutations in its genome, particularly in the RBD region, many of them associated with immune evasion of the host neutralizing antibodies. Some of the viral lineages derived from this evolution have been classified as Variant of Interest (VOI) or Concern (VOC). The neutralizing capacity of a F(ab')2 preparation from sera of horses immunized with viral RBD was evaluated by lytic plaque reduction assay against different SARS-CoV-2 variants. A F(ab')2 preparation of a hyperimmune serum after nine immunizations with RBD exhibited a high titer of neutralizing antibodies against the ancestral-like strain (1/18,528). A reduction in the titer of the F(ab')2 preparation was observed against the different variants tested compared to the neutralizing activity against the ancestral-like strain. The highest reduction in the neutralization titer was observed for the Omicron VOC (4.7-fold), followed by the Mu VOI (2.6), Delta VOC (1.8-fold), and Gamma VOC (1.5). Even if a progressive reduction in the neutralizing antibodies titer against the different variants evaluated was observed, the serum still exhibited a neutralizing titer against the Mu VOI and the Omicron VOC (1/7113 and 1/3918, respectively), the evaluated strains most resistant to neutralization. Therefore, the preparation retained neutralizing activity against all the strains tested.

Updates on Hepatitis B Virus (HBV) Infection 2.0.

Hepatitis B is a "silent epidemic" that is fifty to a hundred (50-100) times more infectious than HIV and is a potentially life-threatening liver infection [...].

Hepatitis B eradication: vaccine as a key player.

OBJECTIVE: Despite the availability of a highly effective and safe vaccine against hepatitis B virus (HBV) infection for 40 years, still almost 300 million persons are estimated to be chronically infected by this virus worldwide. The World Health Organization (WHO) has proposed a plan for hepatitis elimination by 2030. However, several factors, such as the reduction and limitation in vaccination campaigns or vaccine hesitancy (VH) in some regions of the World, might have played a role in limiting the worldwide coverage of hepatitis B prophylaxis. This review aims to describe which factors, such as VH, may be hampering the WHO 2030 goal for hepatitis B eradication. METHODS: The review describes the development and characteristics of the HBV vaccine, from the first plasma-derived to the recombinant one. Eventual limitations in its effectiveness and particularly VH were reviewed. RESULTS: The apparent pitfalls of the HBV vaccine, such as long-term effectiveness, vaccine-escape mutants, and adverse effects, were proven not to be a concern for this vaccine. However, VH persists and was even intensified by the COVID-19 pandemic. CONCLUSIONS: Many barriers still exist, such as vaccine availability, lack of awareness of the benefits of HBV vaccination, and VH. HBV VH seems to be eventually overcome in many settings with active education campaigns and information, stressing the importance of developing these strategies to achieve the 2030 goal of the WHO.

The Hepatitis B Virus Genotypes E to J: The Overlooked Genotypes.

Hepatitis B virus (HBV) genotypes E to J are understudied genotypes. Genotype E is found almost exclusively in West Africa. Genotypes F and H are found in America and are rare in other parts of the world. The distribution of genotype G is not completely known. Genotypes I and J are found in Asia and probably result from recombination events with other genotypes. The number of reported sequences for HBV genotypes E to J is small compared to other genotypes, which could impact phylogenetic and pairwise distance analyses. Genotype F is the most divergent of the HBV genotypes and is subdivided into six subgenotypes F1 to F6. Genotype E may be a recent genotype circulating almost exclusively in sub-Saharan Africa. Genotype J is a putative genotype originating from a single Japanese patient. The paucity of data from sub-Saharan Africa and Latin America is due to the under-representation of these regions in clinical and research cohorts. The purpose of this review is to highlight the need for further research on HBV genotypes E to J, which appear to be overlooked genotypes.

Special Issue: "Updates on HBV Infection".

Hepatitis B virus (HBV) infection remains a global public health issue: a number of barriers still hamper the control of the HBV epidemic and in finding a cure for HBV [...].

Hepatitis B Virus Genotype Study in West Africa Reveals an Expanding Clade of Subgenotype A4.

Hepatitis B virus (HBV) classification comprises up to 10 genotypes with specific geographical distribution worldwide, further subdivided into 40 subgenotypes, which have different impacts on liver disease outcome. Though extensively studied, the classification of subgenotype A sequences remains ambiguous. This study aimed to characterize HBV isolates from West African patients and propose a more advanced classification of subgenotype A. Fourteen HBV full-length genome sequences isolated from patients from The Gambia and Senegal were obtained and phylogenetically analyzed. Phylogenetic analysis of HBV genotype A sequences isolated from Senegalese and Gambian patients exhibited separate clusters from the other known and confirmed subgenotypes A (A1, A2, A6). Most of the sequences (10/14) clustered with an isolate from Cuba, reported as subgenotype A4 (supported by maximal bootstrap value). Four isolates from The Gambia and Senegal clustered separately from all other subgenotypes and samples sequenced in the study. Three of which from The Gambia, designated as an expanding clade of subgenotype A4, exhibited a mean inter-subgenotypic nucleotide divergence over the entire genome sequence higher than 4% in comparison with the other subgenotypes and the other isolates sequenced in the study, except with subgenotype A4 isolates (3.9%), and this was supported by a maximal bootstrap value. The last one from Senegal seemed to be an expanding subgenotype close to the new clade of A4. Amino acid analysis unveiled a novel motif specific to these isolates. This study revealed an expanding evolution of HBV subgenotype A and novel amino acid motifs. It also highlighted the need for a consensus regarding the analysis and classification of HBV sequences.

Mutations in the SARS-CoV-2 spike protein modulate the virus affinity to the human ACE2 receptor, an in silico analysis.

The increasing number of SARS-CoV-2 variants associated with highly transmissible phenotypes is a health-public concern in the current pandemic scenario. Herein, we developed a comprehensive in silico analysis of the changes occurring upon mutations in the viral spike. We focused on mutants located in the receptor-binding domain of the viral spike protein and analyzed whether these mutants modulate the interaction with the human host receptor angiotensin-converting enzyme II (ACE2). Thirty-two highly prevalent mutants were retrieved from the GISAID database, and their structural models were built using the SWISS-Model server. The stabilization effect for each mutation was assessed by the DUET and DeepDGG software. By applying molecular docking using both Z-Dock and Haddock software we found that multiple mutations, including A475V, V455E, V445L, and V445I, resulted in the higher binding free energy as compared to the wild type (WT) spike protein, thus had a destabilizing effect on the binding to ACE2. On the other hand, several mutants, including the most prevalent N501Y and B.1.1.7 variants, as well as the K444R, L455F, Q493R, and Y505W variants exhibited lower binding free energy as compared to the WT spike. These mutants showed an increased number of electrostatic interactions with ACE2 than the WT spike protein, and they changed the interaction pattern of the neighboring residues. Together, the results presented in this study contribute to a better understanding of the changes in the interaction between SARS-CoV-2 and the human host ACE2 receptor associated with point mutations in the viral spike protein.

Prevalence and molecular characterization of hepatitis B virus infection in HIV-infected children in Senegal.

BACKGROUND AND AIMS: Sub-Saharan Africa (SSA) is the region with the most patients co-infected with the human immunodeficiency virus (HIV) and the hepatitis B virus (HBV) worldwide. However, few studies have focused on SSA children who are at a higher risk of developing a chronic infection than adults. Furthermore, children on first-line antiretroviral therapy (ART) including low genetic barrier drugs may develop both HBV and HIV resistance mutations. The aim of this work was to document HIV-HBV co-infection and to characterize the HBV isolates in children in Senegal. METHODS: This is a retrospective study of 613 children infected with HIV on ART or not. Dried blood spot (DBS) specimens were used to detect hepatitis B surface antigen (HBsAg) with a rapid diagnostic test (RDT). Confirmation of HBsAg status and hepatitis B e antigen (HBeAg) detection was performed on an automated platform using the chemiluminescence assay technology. HBV viral DNA was quantified by real-time polymerase chain reaction (PCR) and the preS1/preS2/HBsAg region was genotyped by nested PCR followed by sequencing using the Sanger technique. RESULTS: The prevalence of HIV-HBV co-infection was 4.1% (25/613). The median age of co-infected children was 13 years (2 years-16 years) and 40% (10/25) were girls. Almost all 19/20 (95%) were infected with HIV-1 and 79% (19/24) were treated with 3TC-based triple combination ART. The median duration of time on ART was 15 months (3 months-80 months). More than half of the children 53% (9/17) were experiencing HIV virologic failure and 75% (6/8) had at least one HIV-related resistance-associated mutation (RAM). Of the six children with resistance, none of the three administered treatments were effective on HIV. Of the 25 co-infected children, 82% (18/22) were HBeAg-positive, while the median HBV viral load (VL) was 6.20 log10 IU/mL (24/25 patients), and 62,5% (10/16) of the children had a persistent HBV viremia. Combination of ART was the only factor associated with HBV viremia persistence. Amplification was successful in 15 out of 16 patients (rate of 94%), and the ensuing phylogenetic analysis revealed that eight strains (53%) belonged to genotype A and seven (47%) to genotype E. HBV-related 3TC RAMs were uncovered in 20% of these patients (3/15). HBsAg escape mutations were found in 20% of the children (3/15). CONCLUSIONS: Our results showed a high level of drug resistance mutations to both HIV and HBV, a significant level of HBsAg escape mutations, HBV DNA persistence and HIV virologic failure in co-infected children in Senegal. The HBV genotypes found were A and E.

Unrevealing sequence and structural features of novel coronavirus using in silico approaches: The main protease as molecular target.

Direct-acting antivirals are effective tools to control viral infections. SARS-CoV-2 is a coronavirus associated with the epidemiological outbreak in late 2019. Previous reports showed that HIV-1 protease inhibitors could block SARS-CoV main protease. Based on that and using an in silico approach, we evaluated SARS-CoV-2 main protease as a target for HIV-1 protease inhibitors to reveal the structural features related to their antiviral effect. Our results showed that several HIV inhibitors such as lopinavir, ritonavir, and saquinavir produce strong interaction with the active site of SARS-CoV-2 main protease. Furthermore, broad library protease inhibitors obtained from PubChem and ZINC (www.zinc.docking.org) were evaluated. Our analysis revealed 20 compounds that could be clustered into three groups based on their chemical features. Then, these structures could serve as leading compounds to develop a series of derivatives optimizing their activity against SARS-CoV-2 and other coronaviruses. Altogether, the results presented in this work contribute to gain a deep understanding of the molecular pharmacology of SARS-CoV-2 treatment and validate the use of protease inhibitors against SARS-CoV-2.

Role of changes in SARS-CoV-2 spike protein in the interaction with the human ACE2 receptor: An in silico analysis.

Many human viral diseases are a consequence of a zoonotic event. Some of the diseases caused by these zoonotic events have affected millions of people around the world, some of which have resulted in high rates of morbidity/mortality in humans. Changes in the viral proteins that function as ligands of the host receptor may promote the spillover between species. The most recent of these zoonotic events that have caused an ongoing epidemic of high magnitude is the Covid-19 epidemics caused by SARS-CoV-2. The aim of this study was to determine the mutation(s) in the sequence of the spike protein of the SARS-CoV-2 that might be favoring human to human transmission. An in silico approach was performed, and changes were detected in the S1 subunit of the receptor-binding domain of spike. The observed changes have significant effect on SARS-CoV-2 spike/ACE2 interaction and produce a reduction in the binding energy, compared to the one of the Bat-CoV to this receptor. The data presented in this study suggest a higher affinity of the SARS-Cov-2 spike protein to the human ACE2 receptor, compared to the one of Bat-CoV spike and ACE2. This could be the cause of the rapid viral spread of SARS-CoV-2 in humans.

Antiviral activity of flavonoids present in aerial parts of Marcetia taxifolia against Hepatitis B virus, Poliovirus, and Herpes Simplex Virus in vitro.

Marcetia taxifolia is a neotropical plant present in South America and it has been evaluated in several biological models due to the presence of active metabolites. Nevertheless, there is a limited quantity of studies related to the antiviral activity of the compounds present in this genus. In our work, the antiviral effect of the compounds isolated from the aerial parts of Marcetia taxifolia was evaluated against Hepatitis B virus (HBV), Herpes Simplex Virus type 1 (HSV-1), and Poliovirus type 1 (PV-1). The cytopathic effect and viral quantification by qPCR were determined as indicative of antiviral activity. Our data show that myricetin rhamnoside (MyrG), myricetin-3-α-O-ramnosil (1→6)-α-galactoside (MyrGG), 5,3'-dihydroxy-3,6,7,8,4'-pentamethoxyflavone (PMF), 5-hydroxy-3,6,7,3',4'pentamethoxyflavone (PMF-OH) had antiviral activity without cytotoxic effects. The methoxyflavones PMF and PMF-OH were the most active compounds, showing an antiviral effect against all the evaluated viruses. Computational studies showed that these compounds could interact with the Reverse Transcriptase. Altogether, these results suggest that the flavonoids (related to myricetin and methoxyflavones) are the main antiviral compounds present in the aerial parts of Marcetia taxifolia. Furthermore, our results showed that the methoxyflavones have a broad antiviral activity, which represents an opportunity to evaluate these flavonoids as lead molecules to develop new antiviral compounds.

Performance of molecular methods for identification of unusual subtypes of hepatitis C virus genotype 2

Introduction: Hepatitis C virus (HCV) displays high genetic variability, with seven genotypes and numerous subtypes. The determination of the viral type has been essential for the selection and timing of antiviral treatment. In Venezuela, HCV genotype 2 is relatively diverse, being particularly prevalent subtype 2j. Objective: To evaluate the performance of methodologies for genotyping HCV, particularly for identification of subtype 2j. Materials and methods: HCV genotype and subtype were determined by reverse hybridization technique (LiPA) and sequencing of the HCV 5'UTR and NS5B regions. Results: A total of 65 samples from HCV-infected patients were analyzed. PCR amplifications of the 5'UTR region exhibited the highest sensitivity (100% vs 91% for LiPA and 77% for NS5B). Genotype determination, taking as reference test NS5B, showed 100% concordance with the other methods, and 67% and 59% for subtypes with 5´NC and LiPA, respectively. NS5B sequencing allowed the identification of subtypes 2j and 2s, which were not detected by the other methods. A specific LiPA pattern was not observed for HCV subtype 2j. Conclusion: Although being the methodology with lowest sensitivity for amplification of HCV RNA, sequencing NS5B region remains a powerful tool for correct discrimination of the different HCV subtypes, which is of epidemiological relevance.

Desempeño de métodos moleculares para la identificación de subtipos poco comunes del virus de la hepatitis C, genotipo 2 / Performance of molecular methods for identification of unusual subtypes of hepatitis C virus genotype 2

Resumen Introducción. El virus de la hepatitis C (HCV) presenta una gran variabilidad genética, con siete genotipos y numerosos subtipos. La determinación del tipo viral ha sido fundamental para la escogencia y la duración del tratamiento antiviral adecuado. En Venezuela, el genotipo 2 del HCV es relativamente diverso, siendo particularmente prevalente el subtipo 2j. Objetivo. Evaluar el desempeño de las metodologías para la determinación del genotipo del HCV, particularmente para la identificación del subtipo 2j. Materiales y métodos. Se determinaron el genotipo y el subtipo del HCV mediante la técnica de hibridación inversa LiPA (Line Probe Assay) y secuenciación de las regiones genómicas 5'NC y NS5B del virus. Resultados. En 65 muestras analizadas, la metodología basada en la amplificación de la región 5'NC mostró mayor sensibilidad (100 %), en comparación con la técnica LiPA (91 %) y la secuenciación de la región NS5B (77 %). La determinación de genotipo, tomando como método de referencia la secuenciación de NS5B, mostró un alto grado de concordancia para la secuenciación de la región 5´NC y la hibridación inversa LiPA, con 100 % en la asignación de genotipos, comparado con 70 % y 66 % para los subtipos, respectivamente. La secuenciación de la región NS5B permitió identificar los subtipos 2j y 2s, los cuales no fueron detectados por las otras metodologías. No se observó un patrón característico para las muestras subtipo 2j en la hibridación inversa LiPA. Conclusión. Aunque es la metodología con menor sensibilidad, la secuenciación de la región NS5B es una herramienta poderosa para la correcta discriminación de los distintos subtipos circulantes del HCV, lo cual reviste importancia epidemiológica.

Abstract Introduction: Hepatitis C virus (HCV) displays high genetic variability, with seven genotypes and numerous subtypes. The determination of the viral type has been essential for the selection and timing of antiviral treatment. In Venezuela, HCV genotype 2 is relatively diverse, being particularly prevalent subtype 2j. Objective: To evaluate the performance of methodologies for genotyping HCV, particularly for identification of subtype 2j. Materials and methods: HCV genotype and subtype were determined by reverse hybridization technique (LiPA) and sequencing of the HCV 5'UTR and NS5B regions. Results: A total of 65 samples from HCV-infected patients were analyzed. PCR amplifications of the 5'UTR region exhibited the highest sensitivity (100% vs 91% for LiPA and 77% for NS5B). Genotype determination, taking as reference test NS5B, showed 100% concordance with the other methods, and 67% and 59% for subtypes with 5´NC and LiPA, respectively. NS5B sequencing allowed the identification of subtypes 2j and 2s, which were not detected by the other methods. A specific LiPA pattern was not observed for HCV subtype 2j. Conclusion: Although being the methodology with lowest sensitivity for amplification of HCV RNA, sequencing NS5B region remains a powerful tool for correct discrimination of the different HCV subtypes, which is of epidemiological relevance.

Mutaciones K130M y V131I del gen X en aislados venezolanos del virus de hepatitis B / K130M and V131L Mutations on the X gene of hepatitis B virus in Venezuelan isolates

Aproximadamente el 50% de los carcinomas hepatocelulares (CHC) en el mundo están etiológicamente asociados con la infección por el virus de hepatitis B (VHB). Se han descrito 10 genotipos del VHB (A-J). En Venezuela y en varios países latinoamericanos predomina el genotipo F. Las mutaciones K130M y V131I presentes en la proteína HBx del VHB han sido asociadas al desarrollo del CHC. El objetivo de este trabajo fue estudiar la variabilidad genética de la proteína HBx del VHB circulante en pacientes venezolanos, con el fin de correlacionar estas mutaciones con los parámetros clínicos y virológicos de la enfermedad. Se analizó la secuencia del gen X del VHB, mediante amplificación por PCR de un fragmento de ese gen, en 45 pacientes infectados (35 crónicos y 10 agudos). Se observó una mayor frecuencia de las mutaciones K130M y V131I en pacientes de 25 o más años y con infección crónica. La presencia de estas mutaciones fue significativamente menor en el subgenotipo F3, comparado con el genotipo C. Estos resultados refuerzan la hipótesis de que el subgenotipo F3, predominante en Venezuela, podría estar asociado a una progresión menos severa de la enfermedad que la descrita para otros subgenotipos americanos, como F1b o F2.

Approximately 50% of the hepatocellular carcinomas (HCC) in the world are etiologically associated to hepatitis B virus (HBV) infection. Ten HBV genotypes (A-J) have been described in Venezuela and in other Latin American countries where the F genotype predominates. The K130M and V131I mutations present in the HBx protein of HBV have been associated with the development of HCC. The aim of this work was to study the genetic variability of HBx protein from HBV circulating in Venezuelan patients, in order to correlate these mutations with clinical and virus factors involved in the disease. The X HBV gene sequence was analyzed by PCR amplification of that gene in 45 infected patients (35 with chronic and 10 with acute stages of hepatitis). A higher frequency K130M and V131I mutations was observed in subjects 25 years of age and older with chronic infection. The presence of these mutations was significantly lower in the F3 subgenotype compared with genotype C. These results support the hypothesis that the F3 subgenotype, predominant in Venezuela, could be associated with a less severe progression of the disease than that described for other American subgenotypes, such as F1b or F2.

Infección por el virus de la hepatitis C (HCV) en pacientes hemodializados seronegativos para anticuerpos anti-HCV / Hepatitis C virus (HCV) infection in hemodialysed patients seronegative for anti-HCV antibodies

La infección por el virus de la hepatitis C (HCV) es común en pacientes hemodializados. Se evaluaron 43 sueros de pacientes de la Unidad de Diálisis “Dr. José Maza Carvajal” del Servicio Autónomo del Hospital Universitario “Antonio Patricio de Alcalᔠ(SAHUAPA), en Cumaná, estado Sucre. Se determinaron anticuerpos IgG séricos contra el HCV (anti-HCV) utilizando tres técnicas inmunoenzimáticas. Para amplificar la región 5’ no codificante (5’NC) se usó la técnica de transcripción reversa de la reacción en cadena de la polimerasa (RT-PCR), en muestras positivas y negativas para anti-HCV. La presencia de anticuerpos y RNA del HCV fue de 9,3% y la presencia de RNA del HCV en pacientes con anti-HCV negativos fue de 42%, lo cual representó una frecuencia de infección activa de 51%. Análisis filogenéticos de la región 5’NC evidenciaron que el genotipo 2 fue el más prevalente, en particular el subtipo 2b, seguido por el genotipo 1, mientras que en siete muestras no se logró identificar el subtipo. La presencia de un alto número de pacientes seronegativos e infectados con el HCV puede deberse al estado de inmunocompromiso de estos pacientes; de allí la importancia de la determinación de la viremia.

Hepatitis C virus infection is common in hemodialysed patients. Sera from 43 patients from the Dialysis Unit “Dr. José Maza Carvajal” of the University Hospital “Antonio Patricio de Alcalá”, in Cumana, Sucre state, were evaluated. Antibodies against HCV (anti-HCV) were determined using three immunosorbent assays. The 5 ‘non-coding (5’NC) HCV region was amplified by RT-PCR in all samples. The presence of antibodies and HCV RNA was 9.3% and of HCV RNA in seronegative sera 42%, which represents a frequency of infection of 51%. Phylogenetic analysis of the 5’NC region showed that genotype 2 was the most frequently found, particularly due to subtype 2b, followed by genotype 1, while seven subtypes could not be determined. The presence of a high number of seronegative HCV-infected hemodialysed patients might be due to the immunocompromised condition of these patients; hence the importance of determining the viremia.

HIV-1 and GBV-C co-infection in Venezuela.

INTRODUCTION: Co-infection with GB virus C (GBV-C) in patients infected with human immunodeficiency virus 1 (HIV-1) has been associated with prolonged survival. The aim of this study was to evaluate the prevalence of GBV-C infection among HIV-1-infected patients in Venezuela, and to determine the effects of the co-infection on the levels of relevant cytokines. METHODOLOGY: Plasma samples were collected from 270 HIV-1-seronegative and 255 HIV-1-seropositive individuals. GBV-C infection was determined by RT-PCR of the NS5 region and genotyped by sequence analysis of the 5´UTR region. HIV-1 strains were characterized by sequence analysis of pol, vif, env, and nef genes. Selected cytokines were evaluated by ELISA. RESULTS: Ninety-seven of 525 (18.5%) plasma samples tested positive for GBV-C RNA. A significantly higher prevalence of GBV-C was found among HIV-1 patients compared to HIV-1-seronegative individuals (67/255, 26% versus 30/270, 11%; p < 0.001). Statistical difference was observed in the viral load between HIV-1+GBV-C+ and HIV-1+GBV-C- (p = 0.014), although no differences in CD4+ cell counts were found between both groups. TNFα concentration was higher in HIV-1+GBV-C- than in HIV-1+GBV-C+ patients (25.9 pg/mL versus 17.3 pg/mL; p = 0.02); RANTES expression levels were more variable in GBV-C co-infected patients and more frequently elevated in HIV-1 mono-infected patients compared to patients co-infected with GBV-C. CONCLUSIONS: The previously observed beneficial effect of co-infection with HIV-1 and GBV-C on disease progression is complex and might be due in part to a change in the cytokine environment. More studies are required to understand the interaction between both viruses.

Molecular characterization of hepatitis E virus in patients with acute hepatitis in Venezuela.

Hepatitis E virus (HEV) causes a common infection in developing countries. HEV infection occurs as outbreaks, as sporadic clinical cases and as large epidemics in endemic areas. The objective of this study was to determine the presence of HEV infection in patients with clinical suspicion of hepatitis A virus (HAV) infection, referred to the Instituto Nacional de Higiene "Rafael Rangel" in Venezuela. Seventy-four sera were tested for anti-HAV and anti-HEV IgM antibodies. HEV-RNA was amplified from anti-HEV IgM positive sera using nested reverse transcription polymerase chain reaction for ORF1 (RNA dependent RNA polymerase region) and the amplicons sequenced for phylogenetic analysis. The frequency of anti-HEV IgM was 22/74 (30%) in the samples tested. Dual infection with HAV and HEV was found in 31% (12/39) of anti-HAV IgM positive patients. Viremia was detected in 3/22 (14%) of sera positive for anti-HEV IgM. Two HEV strains were classified as genotype 1 and one as genotype 3, which were closely related to Yam 67 (north of India) and US1 isolates from the USA, respectively. These findings suggest that HEV is an important cause of acute viral hepatitis in Venezuela as a single infection or co-infection with HAV, with high morbidity in children and young adults suggesting that this infection is endemic in Venezuela.

Human papillomavirus in invasive cervical cancer and cervical intraepithelial neoplasia 2 and 3 in Venezuela: a cross-sectional study.

BACKGROUND: This study investigated the distribution of human papillomavirus (HPV) types in invasive cervical cancer (ICC), cervical intraepithelial neoplasia 2 (CIN2) and cervical intraepithelial neoplasia 3 (CIN3) in Venezuela. METHODS: Paraffin-embedded samples from 329 women from 29 medical centers of the 24 states of Venezuela were analyzed to determine the distribution of HPV types for ICC, CIN2, and CIN3, the prevalence of single and multiple infection, and the association of HPV types with severity of lesion, comparing CIN2 versus CIN3+ (CIN3 and ICC). The samples were analyzed with the polymerase chain reaction (PCR) followed by reverse hybridization for the identification of HPV types. RESULTS: HPV was identified in 95/96 ICC specimens (98.9%), in 142/149 CIN3 (95.3%) and in 78/84 CIN2 samples (92.8%). The most common types for ICC and CIN3 were: HPV16, 18, 31, and 33, and for CIN2 were HPV16, 31, 51, 52, and 18. HPV single infection was found in 82.1% of ICC cases, in 79.4% of CIN2 cases, and in 77.4% of CIN3 cases. HPV16 was identified as a single infection more frequently in women with CIN3+ than in those with CIN2 (68.6% versus 46.7%, P=0.002), and HPV16 or HPV18 types were more prevalent in CIN3+ than in CIN2 (73.4% versus 50%, P=0.0006). CONCLUSION: this is the first study of the distribution of HPV types in ICC, CIN2, and CIN3 conducted throughout the territory of Venezuela. HPV16 and HPV18 were the most frequent HPV types identified in single and multiple infections in both ICC and CIN3 groups, and are associated with severity of lesion. The knowledge of the distribution of HPV types would allow organization of an HPV-DNA-based screening test, and consideration of the implementation of prophylactic vaccination in Venezuela.