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Biomedical subjects

Vincent Soriano

Publications and source records attributed to Vincent Soriano.

At least 19 recordsLinked to original sources
PubMed2007

Hepatitis B virus genotypes and lamivudine resistance mutations in HIV/hepatitis B virus-coinfected patients.

BACKGROUND: Differences in subtypes, hepatitis B early antigen (HBeAg)-negative variants, and drug resistance mutations all seem to influence the clinical and therapeutic outcome in patients with chronic hepatitis B virus (HBV) infection. Information available on the prevalence and distribution of distinct HBV variants in HIV-positive patients is scarce. METHODS: All HIV-infected patients with persistent serum hepatitis B surface antigen and detectable HBV viremia were identified in a reference HIV clinic located in Madrid, Spain. HBV load, subtypes, precore (PC) and basal core promoter (BCP) variants, and lamivudine (LAM) resistance mutations were analyzed. RESULTS: A total of 81 HBV/HIV-coinfected patients (4.1%) were identified in a population of 1968 HIV-positive patients. Plasma specimens with detectable HBV viremia could be obtained from 62 subjects, and this was the study population that underwent further virologic characterization. HBV genotype distribution was as follows: A (n = 27), D (n = 27), E (n = 1), F (n = 2), and G (n = 3). Two patients had mixed HBV genotypes (A/E and A/F). HBV subtype A was predominant (74%) among patients infected through sexual contact, whereas HBV-D was most frequent (74%) among intravenous drug users (P < 0.001). PC/BCP mutants were more frequent in patients with HBV-D than in those with HBV-A (63% vs. 18%; P < 0.01). Median time on LAM was 40 months; patients with HBV-A tended to show LAM resistance mutations more often (53% vs. 44%) and to develop them earlier (35 vs. 45 months) than patients with HBV-D. The dual L180M + M204V/I mutant was the predominant resistance pattern, although a triple rt173V + 180M + 204V, which acts as a vaccine escape mutant, was found in 1 individual. In the multivariate analysis, patients with LAM resistance mutations were significantly more frequently HBeAg-positive and older than individuals with wild-type HBV. Hepatitis-delta was recognized in 13 (21%) of these 62 HBV viremic patients, with no association with specific HBV variants. CONCLUSION: Risk transmission group, age, and positive serum HBeAg are the main determinants of distinct HBV virologic variants, including HBV genotypes and LAM-resistant mutants, in HBV/HIV-coinfected patients.

Adult↗
PubMed2007

Genetic factors influencing atazanavir plasma concentrations and the risk of severe hyperbilirubinemia.

BACKGROUND: Hyperbilirubinemia is frequently seen in patients treated with atazanavir (ATV). Polymorphisms at the uridin-glucoronosyl-transferase 1A1 (UGT1A1) and multidrug resistance 1 (MDR1) genes may influence, respectively, bilirubin and ATV plasma concentrations. PATIENTS AND METHODS: HIV-infected individuals receiving ATV 300 mg daily plus ritonavir 100 mg daily at one clinic were examined. ATV plasma concentrations were measured at steady state. MDR1-3435C>T and UGT1A1 polymorphisms were examined in DNA extracted from blood mononuclear cells. RESULTS: A total of 118 patients (all Caucasian) were analysed. The median ATV plasma concentration was 465 ng/ml [interquartile range (IQR), 233-958]. MDR1-3435 genotypes were as follows: CC (32%), CT (47%) and TT (21%). CC patients showed higher ATV minimum concentration than those with CT/TT genotypes: 939 ng/ml (IQR, 492-1266) versus 376 ng/ml (IQR, 221-722) (P = 0.001). In multivariate analyses, having at least one T allele at MDR1-3435 was independently associated with lower ATV plasma concentrations (beta: -427 [95% confidence interval (CI), -633 to -223]; P < 0.001). The proportion of patients with grade 3-4 hyperbilirubinemia varied with distinct UGT1A1 genotypes: 80% for 7/7, 29% for 6/7 and 18% for 6/6 (P = 0.012). In the multivariate analysis, having at least one 7 allele at UGT1A1 was independently associated with severe hyperbilirubinemia (odds ratio, 2.96; 95% CI, 1.29-6.78; P = 0.01). CONCLUSIONS: Polymorphisms at MDR1-3435 significantly influence ATV plasma concentrations, as does being Caucasian patients with CT/TT genotypes, having lower ATV levels, even using ritonavir boosting. On the other hand, although ATV plasma concentrations directly correlate with bilirubin levels, the risk of severe hyperbilirubinemia is further increased in the presence of the UGT1A1-TA7 allele.

Adult↗
PubMed2006

Susceptibility of HIV-1 non-B subtypes and recombinant variants to Enfuvirtide.

BACKGROUND: Data on susceptibility of HIV-1 non-B subtypes to Enfuvirtide (ENF) is rather limited. OBJECTIVE: To determine if ENF could be active in vitro against HIV-1 non-B subtypes and how the gp41 genetic variability across variants may influence ENF susceptibility. METHODS: Using PHENOSCRIPT Env, a recombinant envelope virus assay, ENF susceptibility was investigated in isolates from 19 drug-naive HIV-1-infected individuals harboring non-B subtypes. RESULTS: Using phylogenetic analyses of the gp41 gene, distinct HIV-1 subtypes were recognized: A (2), C (5), D (1), F (2), G (1), J (1), CRF02_AG (6) and CRF06 (1). Susceptibility to ENF and IC(50) values in vitro could be obtained in only 13 (68.4%) specimens, most likely due to the high genetic variability in HR1 and HR2 regions in the remaining cases. A wide range of IC(50) values with a median of 0.013 microg/ml was observed (range, 0.005-0.180 microg/ml). Natural polymorphisms, but not classical ENF resistance associated mutations within HR1 (residues 36-45) were identified in most non-B viruses. CONCLUSION: This study provides information about the baseline susceptibility to ENF in antiretroviral-naive subjects infected with different HIV-1 non-B subtypes. Susceptibility to ENF seems to be preserved despite high genetic variability in HR1 and HR2 regions.

Adult↗
PubMed2006

Evaluation of performance across the dynamic range of the Abbott RealTime HIV-1 assay as compared to VERSANT HIV-1 RNA 3.0 and AMPLICOR HIV-1 MONITOR v1.5 using serial dilutions of 39 group M and O viruses.

Performance of the Abbott m2000 instrument system and the Abbott RealTime HIV-1 assay was evaluated using a panel of 37 group M (subtypes A-D, F, G, CRF01_AE, CRF02_AG and unique recombinant forms) and 2 group O virus isolates. Testing was performed on 273 sample dilutions and compared to VERSANT HIV-1 RNA 3.0 (bDNA) and AMPLICOR HIV-1 MONITOR v1.5 (Monitor v1.5) test results. RealTime HIV-1, bDNA, and Monitor v1.5 tests quantified 87%, 78%, and 81% of samples, respectively. RealTime HIV-1 detected an additional 31 samples at < 40 copies/mL. For group M, RealTime HIV-1 dilution profiles and viral loads were highly correlated with bDNA and Monitor v1.5 values; 87% and 89% of values were within 0.5 log(10) copies/mL. In contrast, the group O viruses were not detected by Monitor v1.5 and were substantially underquantified by approximately 2 log(10) copies/mL in bDNA relative to the RealTime HIV-1 assay. Sequence analysis revealed that RealTime HIV-1 primer/probe binding sites are highly conserved and exhibit fewer nucleotide mismatches relative to Monitor v1.5. The automated m2000 system and RealTime HIV-1 assay offer the advantages of efficient sample processing and throughput with reduced "hands-on" time while providing improved sensitivity, expanded dynamic range and reliable quantification of genetically diverse HIV-1 strains.

Automation↗
PubMed2006

Genetic analysis of the long terminal repeat (LTR) promoter region in HIV-1-infected individuals with different rates of disease progression.

The long terminal repeat (LTR) region of HIV-1 promotes and modulates proviral transcription. LTR genetic variability might influence viral replication and disease progression. Proviral LTR sequences from 32 HIV-1-infected individuals showing different rates of disease progression were examined. Non-progressors (NP, n = 11) were individuals with high and stable CD4 counts and persistently low or undetectable plasma HIV-RNA. Slow progressors (SP, n = 6) were subjects with minimal CD4 decays over time and low plasma HIV-RNA. Typical progressors (TP, n = 15) were individuals with chronic infection showing CD4 counts repeatedly below 500 cells/mul. The mutation frequency within distinct LTR functional regions involved in HIV-1 transcription were compared in these three groups of patients. No significant differences were observed in the mutation frequency in most LTR regulatory sites when comparing the three groups. However, changes in USF regulatory binding sites were more frequent in TP than in SP/NP, while changes in Sp1 binding sites were less common in the former. This is the first study examining the genetic variability of the HIV-1 LTR region in long-term non-progressors showing further divergent outcomes.

Disease Progression↗
PubMed2006

Influence of human T cell lymphotropic virus type 2 coinfection on virological and immunological parameters in HIV type 1-infected patients.

BACKGROUND: Human T cell lymphotropic virus type 2 (HTLV-2) infection is not rare among injection drug users with human immunodeficiency virus (HIV) infection and may exert a protective role in the progression of HIV disease. METHODS: Immunological and virological parameters were compared in HIV-HTLV-2-coinfected patients and a control group of HIV-monoinfected subjects. All individuals were antiretroviral therapy naive. HIV-specific CD8+ T cell levels were measured using an interferon-gamma assay in response to 125 optimally defined HIV peptides divided into 5 pools. Immune activation was evaluated by measuring levels of CD38 in different CD4+ and CD8+ T cell subsets. In a subgroup of patients, the production of CCL4 in parallel with interferon-gamma was assessed in response to Gag peptides. RESULTS: Lower plasma HIV-RNA levels were found in HIV-HTLV-2-coinfected patients than in HIV-monoinfected patients, despite the 2 groups having similar CD4+ T cell counts. Coinfected patients also had significantly lower levels of CD38 expression in total CD8+ T cells and in its naive subset. CD8+ T cell levels specific for each pool of peptides were similar in both groups, but cells mainly contributing to HIV Gag-specific responses in coinfected patients were CCL4 positive and interferon-gamma negative, whereas for HIV-monoinfected subjects, the response was dominated by CCL4-positive and interferon-gamma-positive cells. CONCLUSIONS: HTLV-2 coinfection may exert a protective role on HIV disease progression by lowering HIV replication and immune activation. A predominance of CCL4 single positive HIV-specific CD8+ T cells in HIV-HTLV-2-coinfected patients could explain this effect.

CD8-Positive T-Lymphocytes↗
PubMed2006

Quantitative detection of plasma human immunodeficiency virus type 2 subtype A RNA by the Nuclisens EasyQ Assay (version 1.1).

No commercial viral load assay has yet been approved for use for measurement of human immunodeficiency virus type 2 (HIV-2) RNA levels in plasma. We assessed the performance of the NucliSens EasyQ (version 1.1) assay (EasyQ; bioMérieux, Boxtel, The Netherlands) to quantify HIV-2 viremia. A viral stock was prepared from an HIV-2 (subtype A)-infected patient. Culture supernatant was subjected to viral particle counting by electron microscopy. Serial dilutions of the viral stock were made in HIV-negative plasma and were used to test EasyQ for its sensitivity, linearity, and reproducibility. RNA was quantified by the NucliSens EasyQ (version 1.1) assay. Plasma samples from 75 HIV-2-infected patients were further tested. EasyQ was able to quantify HIV-2 RNA in a reproducible manner. Overall, estimates of the number of HIV-2 RNA copies/ml obtained with EasyQ were lower than those obtained by electron microscopy; however, the differences were always less than 0.7 log (mean, 0.55 +/- 0.19 log(10)). The assay showed good linearity (r(2) = 0.964; P < 0.0001). The agreement between both measures was assessed by use of a Bland-Altman plot; the narrow limits (0.158 to 0.952), defined as the mean difference +/- 2 standard deviations, indicated good agreement. The reproducibility was also good, since the between-run coefficients of variation were 1.49, 3.60, and 12.25% for samples containing 6.30, 4.30, and 2.30 log(10) HIV-2 RNA copies/ml, respectively. HIV-2 RNA was detected in 34 of 75 (45%) plasma specimens (mean, 2.72 log RNA copies/ml; range, 1.74 to 4.11 log RNA copies/ml); the rest of the specimens were considered to have undetectable viremia. A negative correlation was found between the number of HIV-2 RNA copies/ml and CD4 counts. In summary, EasyQ was shown to be reliable for the measurement of plasma HIV-2 subtype A RNA levels and may be a feasible tool for routine clinical monitoring of HIV-2 subtype A-infected patients.

HIV Infections↗
PubMed2006

Natural pregnancies in HIV-serodiscordant couples receiving successful antiretroviral therapy.

Increasing numbers of HIV-serodiscordant heterosexual couples are concerned about the chances for pregnancy. We reviewed all natural pregnancies attained by HIV-serodiscordant couples seen in 3 clinics in Spain, in which the infected partner had undetectable plasma viremia while receiving highly active antiretroviral therapy (HAART). In the case of HIV-infected mothers, only those with undetectable viremia during pregnancy and at delivery were chosen. A total of 62 HIV-serodiscordant couples, 22 HIV-infected women (mean CD4 count of 522 cells/microL, 55% hepatitis C virus [HCV]-seropositive) and 40 HIV-infected men (mean CD4 count of 629 cells/microL, 75% HCV-seropositive), were recorded. Overall, 76 natural pregnancies occurred, and 68 children were born. There were 9 fetal deaths, 1 twin pregnancy, 6 couples with 2 consecutive babies, and 4 couples with 3 consecutive newborns. There were no cases of HIV seroconversion in uninfected sexual partners. One case of vertical HIV transmission occurred, however. Serodiscordant couples attaining natural pregnancy are exposed to a negligible risk of sexual transmission of HIV when the infected partner presents with complete suppression of plasma viremia while receiving HAART.

Adult↗
PubMed2006

Greater CD4 T-cell gains after one year of antiretroviral therapy are associated with lower HIV-1 pol replication capacity.

We sought to determine whether pretreatment low pol replication capacity (polRC) is associated with CD4 T-cell count gains during antiretroviral therapy (ART). Patients were recruited at north American and Australian sites. Viral polRC was measured before starting ART in all subjects. We examined 243 individuals for a median 260 days after initiating ART. Low baseline polRC was associated with greater CD4 T-cell gains independent of virological responses.

Anti-HIV Agents↗
PubMed2006

Combination of tenofovir and lamivudine versus tenofovir after lamivudine failure for therapy of hepatitis B in HIV-coinfection.

OBJECTIVE: At present sequential monotherapy for chronic hepatitis B with hepatitis B virus (HBV)-polymerase inhibitors is clinical practice. It is unknown to date whether combination therapy with lamivudine plus tenofovir could be superior to sequential therapy with tenofovir after the occurrence of lamivudine resistance. METHODS: We conducted a multicenter, 1: 2 matched pair analysis comparing patients with HBV/HIV-coinfection starting an antiretroviral regimen including tenofovir plus lamivudine with patients who had highly replicative, lamivudine resistant HBe-antigen positive chronic hepatitis B and started with tenofovir as the only active HBV polymerase inhibitor subsequent to lamivudine. RESULTS: At baseline patients on tenofovir plus lamivudine (n = 25) had a median HBV DNA of 5.9 x 10(7) copies/ml compared to 1.37 x 10(8) copies/ml in the tenofovir arm (n = 50; P = 0.32). A sustained undetectable HBV DNA < 1000 copies/ml was achieved in 19/25 (76%) patients on tenofovir plus lamivudine and in 42/50 (84%) on tenofovir (P = 0.53). A loss of HBe-antigen was observed in 9/25 (36%) patients on tenofovir plus lamivudine and in 12/50 (24%) patients on tenofovir (P = 0.29). HBs-antigen loss was found in 1/25 (4%) and 3/50 (6%) patients. CONCLUSIONS: In this cohort of HBV/HIV-coinfected individuals, full HBV DNA suppression was achieved in the majority of patients independent of treatment allocation. Loss of HBe- and HBs-antigen was not different between the two study arms. Over a median treatment period of 116 weeks tenofovir was as effective as tenofovir plus lamivudine. Longer treatment periods may be needed to evaluate potential benefits of first-line combination therapy for chronic hepatitis B.

Adenine↗
PubMed2006

Coinfection with hepatitis C virus increases lymphocyte apoptosis in HIV-infected patients.

To test the role of hepatitis C virus (HCV) in CD4 cell depletion in human immunodeficiency virus (HIV)-coinfected patients, T cell apoptosis was measured by annexin V labeling in 31 HIV-infected and 30 HIV-HCV-coinfected patients who were not receiving antiretroviral therapy. Apoptosis in naive CD4(+) T cells and in naive and memory CD8(+) T cells was significantly higher in HIV-HCV-coinfected than in monoinfected patients.

Anti-HIV Agents↗
PubMed2006

Chemoprophylaxis with tenofovir disoproxil fumarate provided partial protection against infection with simian human immunodeficiency virus in macaques given multiple virus challenges.

We examined the efficacy of tenofovir disoproxil fumarate (TDF) in blocking simian human immunodeficiency virus (SHIV) infection in Chinese rhesus macaques. Once weekly for 14 weeks or until a macaque became infected, 12 male macaques were inoculated intrarectally with amounts of SHIV(SF162P3) (10 median tissue culture infective doses; 3.8 x 10(5) virus particles) that were approximately 5-fold higher than the human immunodeficiency virus type 1 RNA levels noted in human semen during an acute infection. Of the 12 macaques, 4 received oral TDF daily, 4 received oral TDF once weekly, and 4 (control animals) received no TDF. The control animals became infected after receiving a median of 1.5 virus inoculations; macaques receiving TDF daily (1 macaque remained uninfected after 14 inoculations) and those receiving TDF weekly became infected after a median duration of 6.0 and 7.0 weeks, respectively. Although infection was delayed in treated macaques, compared with control macaques, the differences were not statistically significant (P=.315); however, the study was limited by the small numbers of animals evaluated and the variability in blood levels of TDF that resulted from oral dosing. These data demonstrate that treatment with oral TDF provided partial protection against SHIV infection but ultimately did not protect all TDF treated animals against multiple virus challenges.

Adenine↗
PubMed2006

Successful rescue therapy with darunabir (TMC114) in HIV-infected patients who have failed several ritonavir-boosted protease inhibitors.

Darunabir, formerly TMC114, is a new protease inhibitor (PI) under clinical development designed to be active against HIV strains resistant to currently available PI. The virological and immunological response to ritonavir-boosted darunabir was assessed in four heavily antiretroviral-experienced patients who had failed enfuvirtide and two or more previous ritonavir-boosted PI regimens, including tipranavir in one instance. All four patients reached undetectable plasma HIV-RNA levels within 8 weeks of therapy and experienced significant CD4 cell count gains.

Antiretroviral Therapy, Highly Active↗
PubMed2006

Seroreversion of HIV antibodies in patients with prolonged suppression of viraemia under HAART.

Prolonged virus suppression in chronically HIV-infected patients could hypothetically lead to antibody seroreversion. Eighty-four HIV-positive individuals with undetectable viraemia for longer than 5 years under HAART were examined. Only one individual, who had initiated HAART shortly after primary HIV infection, showed seroreversion. In contrast, the cure of hepatitis C virus (HCV) with interferon in 25 controls led to the loss of HCV antibodies in most cases. This information indirectly reflects that whereas HCV may be eradicable HIV is not.

Adult↗
PubMed2006

Natural polymorphisms in the protease gene modulate the replicative capacity of non-B HIV-1 variants in the absence of drug pressure.

BACKGROUND: Genetic variation in the HIV-1 pol gene, which encodes the main targets for anti-HIV drugs, may favors different susceptibility and resistance pathways to antiretroviral agents. Several amino acid substitutions occur frequently in some non-B viruses at positions associated with drug resistance in clade B viruses. The clinical relevance of those polymorphisms is unclear. OBJECTIVE: To evaluate the effect of two natural protease (PR) polymorphisms, K20I and M36I, which are frequently found in non-B subtypes, on the virus replicative capacity in the presence and absence of protease inhibitors (PI). STUDY DESIGN: Infectious HIV-1 clones carrying K20I, M36I or K20I/M36I were designed. Their replication kinetics were analyzed by viral competition in the absence of PI. Susceptibility to six different PI was phenotypically assessed in clones and in recombinant viruses carrying non-B proteases from 16 drug-naive individuals. RESULTS: In the absence of drug, the M36I clone replicated more rapidly than wt (wild type) or the double mutant K20I/M36I. Natural polymorphisms 20I and/or 36I improved the virus replicative capacity under drug pressure, reducing the susceptibility to saquinavir and indinavir, with IC(50) values 2-3.5-fold higher than wt. All but one drug-naive individual carrying non-B viruses were fully susceptibility to all tested PI, suggesting that additional substitutions within the PR might compensate the reduced PI susceptibility caused by K20I and/or M36I. CONCLUSION: Natural PR polymorphisms in non-B HIV-1 variants can influence in vitro the virus replication capacity in the presence and/or absence or certain PI. Hypothetically, the improved viral replication of mutant 36I might favor a more rapid spreading of non-B subtypes of HIV-1.

Coculture Techniques↗
PubMed2006

Prevalence of the HIV-1 protease mutation I47A in clinical practice and association with lopinavir resistance.

Mutation proI47A has recently been associated with lopinavir/ritonavir (LPV/r) resistance. Only four out of 1859 specimens (0.2%) sent for drug resistance testing (219 drug-naive and 1650 antiretroviral-experienced) showed I47A. All belonged to patients failing LPV/r. The prevalence among protease inhibitor-experienced patients was 0.6%. Phenotypic testing showed that proI47A caused high-level lopinavir resistance (> 100-fold) and cross-resistance to amprenavir, whereas it caused hypersusceptibility to saquinavir. ProI47A should thus be considered the primary lopinavir resistance mutation.

Carbamates↗
PubMed2006

Changes in the distribution of hepatitis C virus (HCV) genotypes over time in Spain according to HIV serostatus: implications for HCV therapy in HCV/HIV-coinfected patients.

BACKGROUND: Changes in the prevalence of distinct hepatitis C virus (HCV) genotypes and subtypes over time have not been explored in detail. METHODS: A retrospective analysis was carried out in all specimens from subjects with chronic hepatitis C sent for testing to a reference laboratory in Spain since 1998-2004. RESULTS: A total of 1226 distinct subjects were analyzed. The most frequent HCV genotype was 1 (64.1%), followed by 3 (20.9%) and 4 (11.7%). The most frequent HCV subtype was 1b (32.4%). A total of 797 patients (65%) were HIV-positive. Although genotype 1 was the most frequent, it represented 74.6% of HIV-negative and 58.5% of HIV-positive patients (p<0.01). While HCV subtype 1a was the most frequent among HIV-positive subjects (32.1%), 1b was the most common in HIV-negative patients (53.8%). There was a significant increase in the prevalence of genotype 4 and conversely a decline in genotype 3 among HIV-positive patients over time. CONCLUSION: Genotype 1 is the most frequent HCV variant circulating in Spain. Genotypes 3 and 4 are significantly more prevalent in HIV/HCV-coinfected than in HCV-monoinfected patients. However, HCV-3 has declined and HCV-4 is increasing in the former group. These findings are relevant given their different susceptibility to interferon-based therapies.

Adult↗