Phage display selection of HIV specific conserved mimotopes with IgG from long-term non-progressors

Poster presentation Background The aim of this study is to identify conserved epitopes of HIV-1 neutralizing antibodies in polyclonal plasma from LTNP to finally derive vaccine candidates. Materials and methods The presence of neutralizing antibodies in 9 LTNP sera was proved by in vitro neutralization assays. Phage displayed peptide libraries were screened with LTNP IgG. HIV-specific mimotopes were analyzed for homology to the gp120 structure by a software (3DEX) especially developed for this purpose. Mice were immunized with interesting phages and their sera were analyzed for neutralizing activities against HIV-1. Results After biopannings, between 19% and 75% HIV-specific phage clones were identified by ELISA. Mimotope sequences were identified and could be aligned by 3DEX to linear or conformational epitopes on gp120. A peptide specific immune response was detected in sera of immunized mice. The first mice sera analyzed showed neutralizing activities against HIV-1. Conclusion Mimotopes could be selected from LTNP sera that represent conformational epitopes on gp120. Those ones inducing neutralizing antibodies upon immunization potentially are suited to derive vaccine candidates

Development of water-soluble polyanionic carbosilane dendrimers as novel and highly potent topical anti-HIV-2 microbicides

This is the author’s version of a work that was accepted for publication in Nanoscale."The development of topical microbicide formulations for vaginal delivery to prevent HIV-2 sexual transmission is urgently needed. Second- and third-generation polyanionic carbosilane dendrimers with a silicon atom core and 16 sulfonate (G2-S16), napthylsulfonate (G2-NS16) and sulphate (G3-Sh16) end-groups have shown potent and broad-spectrum anti-HIV-1 activity. However, their antiviral activity against HIV-2 and mode of action have not been probed. Cytotoxicity, anti-HIV-2, anti-sperm and antimicrobial activities of dendrimers were determined. Analysis of combined effects of triple combinations with tenofovir and raltegravir was performed by using CalcuSyn software. We also assessed the mode of antiviral action on the inhibition of HIV-2 infection through a panel of different in vitro antiviral assays: attachment, internalization in PBMCs, inactivation and cell-based fusion. Vaginal irritation and histological analysis in female BALB/c mice were evaluated. Our results suggest that G2-S16, G2-NS16 and G3-Sh16 exert anti-HIV-2 activity at an early stage of viral replication inactivating the virus, inhibiting cell-to-cell HIV-2 transmission, and blocking the binding of gp120 to CD4, and the HIV-2 entry. Triple combinations with tenofovir and raltegravir increased the anti-HIV-2 activity, consistent with synergistic interactions (CIwt: 0.33–0.66). No vaginal irritation was detected in BALB/c mice after two consecutive applications for 2 days with 3% G2-S16. Our results have clearly shown that G2-S16, G2-NS16 and G3-Sh16 have high potency against HIV-2 infection. The modes of action confirm their multifactorial and non-specific ability, suggesting that these dendrimers deserve further studies as potential candidate microbicides to prevent vaginal/rectal HIV-1/HIV-2 transmission in humans.

EBioMedicine

BACKGROUND: Previous epigenome-wide association studies have shown that HIV infection can disrupt the host DNA methylation landscape. However, it remains unclear how antiretroviral therapy (ART) affects the HIV-induced epigenetic modifications. METHODS: 184 individuals with HIV from the NEAT001/ANRS143 clinical trial (with pre-ART and post-ART samples [96 weeks of follow-up]) and 44 age-and-sex matched individuals without HIV were included. We compared genome-wide DNA methylation profiles in whole blood between groups adjusting for age, sex, batch effects, and DNA methylation-based estimates of leucocyte composition. FINDINGS: We identified 430 differentially methylated positions (DMPs) between HIV+ pre-ART individuals and HIV-uninfected controls. In participants with HIV, ART initiation modified the DNA methylation levels at 845 CpG positions and restored 49.3% of the changes found between HIV+ pre-ART and HIV-uninfected individuals. We only found 15 DMPs when comparing DNA methylation profiles between HIV+ post-ART individuals and participants without HIV. The Gene Ontology enrichment analysis of DMPs associated with untreated HIV infection revealed an enrichment in biological processes regulating the immune system and antiviral responses. In participants with untreated HIV infection, DNA methylation levels at top HIV-related DMPs were associated with CD4/CD8 ratios and viral loads. Changes in DNA methylation levels after ART initiation were weakly correlated with changes in CD4+ cell counts and the CD4/CD8 ratio. INTERPRETATION: Control of HIV viraemia after 96 weeks of ART initiation partly restores the host DNA methylation changes that occurred before antiretroviral treatment of HIV infection. FUNDING: NEAT-ID Foundation and Instituto de Salud Carlos III, co-funded by European Union

La carpeta de aprendizaje como herramienta de innovación docente: experiencia piloto en la asignatura de bioquímica

La adaptación al nuevo Espacio Europeo de Educación Superior (EEES) supone desarrollar un modelo educativo centrado en el alumno, que demanda la utilización de metodologías activas de aprendizaje, promotoras del desarrollo de competencias transversales y específicas, como parte de la formación integral del estudiante. Para satisfacer estas demandas, el equipo docente de la asignatura de Bioquímica en 1º de Odontología, ha propuesto la realización de una carpeta de aprendizaje elaborada por el estudiante, como un elemento de enseñanza-aprendizaje y evaluación. La experiencia se ha llevado a cabo en los 9 grupos de estudiantes de este grado en la Universidad Europea de Madrid (UEM) y ha consistido en una colección de evidencias realizada por el alumno, representativa de su trabajo en esta asignatura, presentada de forma individual y evaluada mediante una rúbrica que contempla el desarrollo académico y de competencias. Se ha analizado el posible impacto de la realización de esta carpeta sobre las calificaciones, así como las reflexiones y valoraciones hechas por los estudiantes en una encuesta de satisfacción. Los resultados muestran una aceptación moderada de esta herramienta por parte del estudiante. El equipo docente valora positivamente esta primera experiencia y se plantea aplicar mejoras sustanciales para el futuro.SIN FINANCIACIÓNNo data 2012UE

Impact of nucleos(t)ide reverse transcriptase inhibitors on blood telomere length changes in a prospective cohort of aviremic HIV-infected adults

[Background]: Tenofovir is a potent inhibitor of human telomerase. The clinical relevance of this inhibition is unknown.[Methods]: A prospective cohort of human immunodeficiency virus (HIV)–infected participants with suppressed virological replication was recruited to compare whole-blood telomere length (measured by quantitative multiplex polymerase chain reaction analysis) in participants with current exposure to tenofovir disoproxil fumarate (TDF) to that in participants never exposed to TDF.[Results]: A total of 172 participants were included: 67 were in the TDF group, and 105 were in the non-TDF group (75 were receiving 2 nucleosides [of whom 69 were receiving abacavir], 25 were receiving a nucleos[t]ide reverse transcriptase inhibitor [N{t}RTI]–sparing regimen, and 5 were receiving lamivudine as the only nucleoside). After 2 years, the mean blood telomere length increased significantly in the whole cohort. The TDF group had significantly smaller gains in telomere length than the non-TDF group. In the analysis restricted to participants receiving N(t)RTIs, TDF exposure was not associated with an independent negative effect. In the non-TDF group, participants treated with 2 nucleosides also had significantly smaller gains in telomere length than those receiving N(t)RTI-sparing regimens or lamivudine as the only nucleoside.[Discussion]: In HIV-infected adults with prolonged virological suppression, treatment with TDF or abacavir was associated with smaller gains in blood telomere length after 2 years of follow-up.This work was supported by the Fondo de Investigaciones Sanitarias, Instituto de Salud Carlos III (grants PI13/01467 and PI14/01495 [supported by the European Regional Development Fund], Rio Hortega fellowship [to R. d. M.], and predoctoral fellowship [to N. S.-A.]).Peer reviewe

Epigenetic age acceleration changes 2 years after antiretroviral therapy initiation in adults with HIV: a substudy of the NEAT001/ANRS143 randomised trial

BACKGROUND: DNA methylation-based estimators of biological age are reliable biomarkers of the ageing process. We aimed to investigate a range of epigenetic ageing biomarkers in a substudy of the NEAT001/ANRS143 clinical trial, which compared ritonavir-boosted darunavir with either raltegravir or tenofovir disoproxil fumarate and emtricitabine in antiretroviral therapy (ART)-naive adults. METHODS: We analysed frozen whole blood samples from 168 ART-naive participants with HIV from the NEAT001/ANRS143 trial, before ART initiation and after 2 years of ART (84 participants on ritonavir-boosted darunavir with raltegravir and 84 participants on ritonavir-boosted darunavir with tenofovir disoproxil fumarate and emtricitabine). We also included 44 participants without HIV with a similar age and sex distribution. We analysed DNA methylation. Epigenetic age estimators (Horvath's clock, Hannum's clock, GrimAge, and PhenoAge) and estimated leucocyte compositions were generated using Horvath's New Online Methylation Age Calculator and Houseman's method. We calculated epigenetic age acceleration measures for each estimator of epigenetic age. The NEAT001/ANRS143 trial is registered with ClinicalTrials.gov, NCT01066962. FINDINGS: Compared with the HIV-uninfected group, ART-naive participants with HIV showed higher epigenetic age acceleration (EAA) according to all EAA estimators (mean 2·5 years, 95% CI 1·89-3·22 for Horvath-EAA; 1·4 years, 0·74-1·99 for Hannum-EAA; 2·8 years, 1·97-3·68 for GrimAge-EAA; and 7·3 years, 6·40-8·13 for PhenoAge-EAA), with all differences being statistically significant except for Hannum-EAA (Horvath-EAA p=0·0008; Hannum-EAA p=0·059; GrimAge-EAA p=0·0021; and PhenoAge-EAA p<0·0001). Epigenetic ageing was more pronounced in participants who had CD4 counts less than 200 cells per μL (significant for PhenoAge and Hannum's clock, p=0·0015 and p=0·034, respectively) or viral loads over 100 000 copies per mL at baseline (significant for PhenoAge, p=0·017). After 2 years of ART, epigenetic age acceleration was reduced, although PhenoAge and GrimAge remained significantly higher in participants with HIV compared with participants without HIV (mean difference 3·69 years, 95% CI 1·77-5·61; p=0·0002 and 2·2 years, 0·47-3·99; p=0·013, respectively). There were no significant differences in the ART effect on epigenetic ageing between treatment regimens. At baseline, participants with HIV showed dysregulation of DNA methylation-based estimated leucocyte subsets towards more differentiated T-cell phenotypes and proinflammatory leucocytes, which was also partly restored with ART. INTERPRETATION: ART initiation partly reversed epigenetic ageing associated with untreated HIV infection. Further studies are needed to understand the long-term dynamics and clinical relevance of epigenetic ageing biomarkers in people with HIV. FUNDING: NEAT-ID Foundation

The major genetic determinants of HIV-1 control affect HLA class I peptide presentation.

Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified &gt;300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA-viral peptide interaction as the major factor modulating durable control of HIV infection

Quality Control Assessment of Human Immunodeficiency Virus Type 2 (HIV-2) Viral Load Quantification Assays: Results from an International Collaboration on HIV-2 Infection in 2006▿

Human immunodeficiency virus type 2 (HIV-2) RNA quantification assays used in nine laboratories of the ACHIEV2E (A Collaboration on HIV-2 Infection) study group were evaluated. In a blinded experimental design, laboratories quantified three series of aliquots of an HIV-2 subtype A strain, each at a different theoretical viral load. Quantification varied between laboratories, and international standardization of quantification assays is strongly needed