Glycosystems in nanotechnology: Gold glyconanoparticles as carrier for anti-HIV prodrugs

The therapeutic approach for the treatment of HIV infection is based on the highly active antiretroviral therapy (HAART), a cocktail of antiretroviral drugs. Notwithstanding HAART has shown different drawbacks like toxic side effects and the emergence of viral multidrug resistance. Nanotechnology offers new tools to improve HIV drug treatment and prevention. In this scenario, gold nanoparticles are an interesting chemical tool to design and prepare smart and efficient drug-delivery systems. Here we describe the preparation and antiviral activity of carbohydrate-coated gold nanoparticles loaded with anti-HIV prodrug candidates. The nucleoside reverse transcriptase inhibitors abacavir and lamivudine have been converted to the corresponding thiol-ending ester derivatives and then conjugated to ~3 nm glucose-coated gold nanoparticles by means of “thiol-for-thiol” ligand place exchange reactions. The drugs-containing glyconanoparticles were characterized and the pH-mediated release of the drug from the nanoparticle has been determined. The antiviral activity was tested by evaluating the replication of NL4-3 HIV in TZM-bl infected cells. The proof-of-principle presented in this work aims to introduce gold glyconanoparticles as a new multifunctional drug-delivery system in the therapy against HIV

Evaluation of the Thermal Stability of a Vaccine Prototype Based on Virus-like Particle Formulated HIV-1 Envelope

The long-term storage stability of vaccines has a major impact on the roll-out and success of global immunization programs. For the Human Immunodeficiency Virus type 1 (HIV-1) virus-like particle (VLP) vaccine prototype evaluated here, nanoparticle tracking analysis (NTA), and enzyme-linked immunoabsorbent assay (ELISA) results demonstrated a remarkable structural stability. VLPs maintained their integrity and the recognition of relevant B-cell epitopes for three months at 4 and -20 °C. Interestingly, most particles remained intact and preserved the recognition of relevant epitopes even after a week of storage at room temperature.This research was funded by Instituto de Salud Carlos III within the Spanish AIDS Research Network (RIS), grant number RD16CIII/0002/0001 (Plan Estatal de I + D + I 2013-2016) and cofunded by European Regional Development Fund (ERDF) “A way to build Europe”. This study was also supported by the Spanish Ministry of Science, Innovation and University, Instituto de Salud Carlos III [PI17CIII-00049 (MPY126/18)] and the Spanish Ministry of Science and Innovation, Instituto de Salud Carlos III [PI20CIII-00039 (MPY315/20)]. This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement no. 681137 (EAVI-2020).S

Potent Induction of Envelope-Specific Antibody Responses by Virus-Like Particle Immunogens Based on HIV-1 Envelopes from Patients with Early Broadly Neutralizing Responses

Longitudinal studies in HIV-1 infected individuals have indicated that 2-3 years of infection are required to develop broadly neutralizing antibodies. However, we have previously identified individuals with broadly neutralizing activity (bNA) in early HIV-1 infection, indicating that a vaccine may be capable of bNA induction after short periods of antigen exposure. Here, we describe 5 HIV-1 envelope sequences from individuals who have developed bNA within the first 100 days of infection (early neutralizers) and selected two of them to design immunogens based on HIV-1-Gag virus like particles (VLPs). These VLPs were homogeneous and incorporated the corresponding envelopes (7 to 9μg of gp120 in 1010 VLPs). Both envelopes bound to well-characterized bNAbs, including trimer-specific antibodies (PGT145, VRC01 and 35022). For immunogenicity testing, we immunized rabbits with the Env-VLPs or with the corresponding stabilized soluble Envelope trimers. A short immunization protocol (105 days) was used to recapitulate the early nAb induction observed after HIV-1 infection in these two individuals. All VLP and trimeric Envelope immunogens induced a comparably strong anti-gp120 response, despite having immunized rabbits with 30 times less gp120 in the case of the Env-VLPs. In addition, animals immunized with VLP-formulated Envs induced antibodies that cross-recognized the corresponding soluble stabilized trimer and vice versa, even though no neutralizing activity was observed. Nevertheless, our data may provide a new platform of immunogens, based on HIV-1 envelopes from patients with early broadly neutralizing responses, with the potential to generate protective immune responses using vaccination protocols similar to those used in classical preventive vaccines. Importance: It is generally accepted that an effective HIV-1 vaccine should be able to induce broad-spectrum neutralizing antibodies. Since most of these antibodies require long periods of somatic maturation in vivo, several groups are developing immunogens, based on the HIV envelope protein, that require complex and lengthy immunization protocols that would be difficult to implement to the general population. Here, we show that rabbits immunized with new envelopes (VLP-formulated) from two individuals who demonstrated broadly neutralizing activity very early after infection, induced specific HIV-1 antibodies after a short immunization protocol. This evidence provides the basis for generating protective immune responses with classic vaccination protocols with vaccine prototypes based on HIV envelope sequences from individuals who have developed early broadly neutralizing responses.This project received funding from the European Union's Horizon 2020 research and innovation program under grant agreement no. 681137 to I.B., N.G., A.O., C.B., J.A., R.W.S., and E.Y. It was also partially supported by the Spanish AIDS Research Network (RIS), funded by the Instituto de Salud Carlos III and co-funded by the European Regional Development Fund (ERDF) “A way to build Europe” (projects RD16CIII/0002/0001, RD16CIII/0002/0005, and RD16CIII/0025/0041), Plan Estatal de I1D1I 2013-2016 to N.G., A.M.M., J.A., V.S.M., E.Y., M.P., A.O., and C.B.; by IDIBAPS to J.M.M. (80:20 Research grant); by the Fondation Dormeur, Vaduz to C.B.; by the Ministerio de Economía, Industria y Competitividad to N.G., V.S.M., and E.Y. (PI17CIII/00049); by the Ministerio de Ciencia e Innovación to N.G., V.S.M., and E.Y. (PI20CIII/00039); by the Consejo Nacional de Innovación, Ciencia y Tecnología to C.B.P.; and by the HHS/ National Institutes of Health (NIH) to C.B. (P01-AI131568).S

Spanish adaptation of the 2016 European Guidelines on cardiovascular disease prevention in clinical practice

The VI European Guidelines for Cardiovascular Prevention recommend combining population and high-risk strategies with lifestyle changes as a cornerstone of prevention, and propose the SCORE function to quantify cardiovascular risk. The guidelines highlight disease specific interventions, and conditions as women, young people and ethnic minorities. Screening for subclinical atherosclerosis with noninvasive imaging techniques is not recommended. The guidelines distinguish four risk levels (very high, high, moderate and low) with therapeutic objectives for lipid control according to risk. Diabetes mellitus confers a high risk, except for subjects with type 2 diabetes with less than <10 years of evolution, without other risk factors or complications, or type 1 diabetes of short evolution without complications. The decision to start pharmacological treatment of arterial hypertension will depend on the blood pressure level and the cardiovascular risk, taking into account the lesion of target organs. The guidelines don't recommend antiplatelet drugs in primary prevention because of the increased bleeding risk. The low adherence to the medication requires simplified therapeutic regimes and to identify and combat its causes. The guidelines highlight the responsibility of health professionals to take an active role in advocating evidence-based interventions at the population level, and propose effective interventions, at individual and population level, to promote a healthy diet, the practice of physical activity, the cessation of smoking and the protection against alcohol abuse.S

HIV-1 Dual Infected LTNP-EC Patients Developed an Unexpected Antibody Cross-Neutralizing Activity

This study evaluated the neutralization breadth in dually infected (DI) HIV-1 long-term non-progressor elite controller patients (LTNP-EC) using a representative minipanel of 6 viruses from 5 different subtypes. Our results showed an improved neutralization breadth in DI LTNP-EC patients when compared with matched LTNP single-infected patients. The role of viral diversity in neutralization was estimated with the Shannon Entropy and the p-distance in viral quasispecies. We found a positive correlation between neutralization breadth and diversity within the viral quasispecies. This correlation could explain why a group of LTNP-EC patients developed a broad neutralizing response despite having undetectable levels of viremia.Work in CNM is supported by grants from Fundacion para la Investigación del Sida en España (www.fipse.es) and (PI 13/02269) Fondo de Investigación Sanitaria (ISCIII) (www.isciii.es) to CL. Red de Investigación en SIDA www.retic-ris.net to CL. A grant RD12/0017/0036 to CL as part of the Plan Nacional R D+I and cofinanced by ISCIII (www.isciii.es) - Subdirección General de Evaluación y el Fondo Europeo de Desarrollo Regional (FEDER). CL IDIBAPS work was supported by a grant (RYC-2007-00788) to EY from the Ministerio de Ciencia y Tecnologia www.micinn.es, a grant (PS09/01459) to EY from the Fondo de Investigaciones Sanitarias (ISCIII) (www.isciii.es).S

Soil heterotrophic CO2 emissions from tropical high-elevation ecosystems (Páramos) and their sensitivity to temperature and moisture fluctuations

Increasing temperatures and changes in the intensity and frequency of precipitations may impact the ability of tropical high-elevation Andean ecosystems (Páramos) to store and retain carbon (C). We, therefore, examined how warming and fluctuations in soil moisture could influence soil CO emissions from heterotrophic respiration (R, the result of microbial respiration), of two Páramos of contrasting climatic regimes within their area of distribution. We here show high sensitivity of both R and Q under warmer and fluctuating moisture conditions. Together with the high rates of C-normalized R compared to other soil C-rich ecosystems from higher latitudes (2 μmol gC h versus 0,4 μmol gC h, respectively) our results evidenced how soil heterotrophic-derived CO emissions could potentially increase under expected climate scenarios, eventually altering the capacity of soil Páramos to sequester C.This work was supported by >becas Santander para jovenes investigadores> and the project VERONICA (CGL 2013-42271-P) Spanish Ministry for Economy and Competitiveness (MINECO).Peer Reviewe

Potent Antibody-Mediated Neutralization and Evolution of Antigenic Escape Variants of Simian Immunodeficiency Virus Strain SIVmac239 In Vivo▿

Here, we describe the evolution of antigenic escape variants in a rhesus macaque that developed unusually high neutralizing antibody titers to SIVmac239. By 42 weeks postinfection, 50% neutralization of SIVmac239 was achieved with plasma dilutions of 1:1,000. Testing of purified immunoglobulin confirmed that the neutralizing activity was antibody mediated. Despite the potency of the neutralizing antibody response, the animal displayed a typical viral load profile and progressed to terminal AIDS with a normal time course. Viral envelope sequences from week 16 and week 42 plasma contained an excess of nonsynonymous substitutions, predominantly in V1 and V4, including individual sites with ratios of nonsynonymous to synonymous substitution rates (dN/dS) highly suggestive of strong positive selection. Recombinant viruses encoding envelope sequences isolated from these time points remained resistant to neutralization by all longitudinal plasma samples, revealing the failure of the animal to mount secondary responses to the escaped variants. Substitutions at two sites with significant dN/dS values, one in V1 and one in V4, were independently sufficient to confer nearly complete resistance to neutralization. Substitutions at three additional sites, one in V4 and two in gp41, conferred moderate to high levels of resistance when tested individually. All the amino acid changes leading to escape resulted from single nucleotide substitutions. The observation that antigenic escape resulted from individual, single amino acid replacements at sites well separated in current structural models of Env indicates that the virus can utilize multiple independent pathways to rapidly achieve similar levels of resistance