Egas Moniz Interdisciplinary Research Center

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Publications

Treatment and cure of HIV infection : available drugs, resistance pathways, and promising new compounds

Publication . Moura, Ines; Taveira, Nuno Eduardo Moura dos Santos da Costa; Sousa, Ana Espada de; Gonçalves, João Manuel Braz

Human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2) are the cause of acquired immunodeficiency syndrome (AIDS). What was once a death sentence has become a chronically manageable condition with the introduction of antiretroviral therapy (ART). Although HIV-2 infection has a much lower prevalence than HIV-1 infection, its intrinsic resistance to specific classes of antiretroviral drugs (ARVs) presents substantial challenges in the treatment of affected individuals. Recognizing the importance of addressing these challenges, our research focuses on the identification of drug resistance mutations and the exploration of novel compounds to devise more potent treatment strategies tailored specifically to HIV-2 infection. In the initial segment of this thesis, we present two key projects: The first project involves identifying resistance mutations in people living with HIV-2 experiencing treatment failure in Cape Verde. The second project aims to analyze the efficacy of integrase inhibitors and a new spiro-β-lactam compound against both naïve and raltegravir (RAL)-resistant isolates from Portuguese HIV-2-infected individuals. The initial project outcomes revealed a high prevalence (76.5%) of resistance mutations in people from Cape Verde living with HIV-2 experiencing virological failure. These mutations, located in the reverse transcriptase (RT) and protease (PR), confer resistance against the majority of RT and PR inhibitors. This underscores the imperative for incorporating integrase inhibitors into treatment regimens to effectively address this resistance. In the second project, the results confirmed the robust efficacy of integrase inhibitors, specifically RAL and DTG, against HIV-2 isolates. This aligns with the established clinical efficacy of RAL and DTG in managing HIV-2 infection. The compelling activity observed with the new integrase inhibitor BIC and the novel spiro-β-lactam BSS-730A, even in the face of multi-drug resistant isolates, holds promising prospects for the clinical application of these drugs. While ART has undeniably transformed the landscape of HIV management, the pursuit of an HIV cure remains a crucial endeavor to alleviate the enduring burden of lifelong therapy. Achieving a cure necessitates the elimination of latent virus reservoirs, making a functional cure a more pragmatic goal. Consequently, the second segment of this thesis encompasses two projects dedicated to advancing our understanding and contributing to the cure of HIV infection. The first project entails the development and antiviral evaluation of a compound, Apsi510, which combines an anti-integrase aptamer (T30695) with a small interfering RNA (siRNA) targeting the TAR/poly A region of HIV-1. Notably, the Apsi510 compound exhibited potent antiviral activity against HIV-1, with a remarkable inhibition of over 95% of viral replication observed at a concentration of 50 nM. The siRNA, designed to target the TAR/poly A region, demonstrated efficacy in inhibiting viral transcription, suggesting its potential application in a functional cure approach. In the second project, the investigation into the role of FUBP3 in the regulation of HIV transcription revealed promising findings. Depletion of FUBP3 resulted in a substantial reduction in viral messenger RNA and p24 protein, indicating a significant inhibition of HIV replication. This inhibition persisted even in the presence of an HIV transcription activator compound. Furthermore, the results underscored that the inhibition of FUBP3 protein expression led to a diminished recruitment of RNA polymerase II to the HIV-1 promoter, emphasizing the pivotal role of FUBP3 in the regulation of HIV transcription. As such, these findings position FUBP3 as a compelling candidate for consideration as a potential target in functional cure strategies, particularly through the block-and-lock approach. In summary, our data significantly contributes to the ongoing development of advanced algorithms aimed at predicting treatment susceptibility for HIV-2 infection. Additionally, our research introduces novel compounds that hold promise for the treatment of HIV-2 infection. Furthermore, we present a novel and potent HIV-1 antiviral compound that has potential implications for advancing strategies towards the cure of HIV-1 infection. Concurrently, our work underscores the viability of FUBP3 as a target for functional cure strategies in HIV infection. It is imperative to acknowledge that the ultimate goal in the battle against HIV infection lies in a comprehensive approach, combining multiple strategies and the judicious use of ART. Furthermore, recognizing the unique characteristics of HIV-2, including its lower infectivity and propensity for latency, underscores the importance of tailoring strategies specifically to HIV-2. Insights derived from such tailored approaches may prove instrumental in the development of effective functional cure strategies.

2024-04Doctoral thesis

Embargoed access

An HIV-1/HIV-2 Chimeric Envelope Glycoprotein Generates Binding and Neutralising Antibodies against HIV-1 and HIV-2 Isolates

Publication . Taveira, Nuno; Figueiredo, Inês; Calado, Rita; Martin, Francisco; Bártolo, Inês; Marcelino, José Maria; Borrego, Pedro; Cardoso, Fernando M H; Barroso, Helena

The development of immunogens that elicit broadly reactive neutralising antibodies (bNAbs) is the highest priority for an HIV vaccine. We have shown that a prime-boost vaccination strategy with vaccinia virus expressing the envelope glycoprotein gp120 of HIV-2 and a polypeptide comprising the envelope regions C2, V3 and C3 elicits bNAbs against HIV-2. We hypothesised that a chimeric envelope gp120 containing the C2, V3 and C3 regions of HIV-2 and the remaining parts of HIV-1 would elicit a neutralising response against HIV-1 and HIV-2. This chimeric envelope was synthesised and expressed in vaccinia virus. Balb/c mice primed with the recombinant vaccinia virus and boosted with an HIV-2 C2V3C3 polypeptide or monomeric gp120 from a CRF01_AG HIV-1 isolate produced antibodies that neutralised >60% (serum dilution 1:40) of a primary HIV-2 isolate. Four out of nine mice also produced antibodies that neutralised at least one HIV-1 isolate. Neutralising epitope specificity was assessed using a panel of HIV-1 TRO.11 pseudoviruses with key neutralising epitopes disrupted by alanine substitution (N160A in V2; N278A in the CD4 binding site region; N332A in the high mannose patch). The neutralisation of the mutant pseudoviruses was reduced or abolished in one mouse, suggesting that neutralising antibodies target the three major neutralising epitopes in the HIV-1 envelope gp120. These results provide proof of concept for chimeric HIV-1/HIV-2 envelope glycoproteins as vaccine immunogens that can direct the antibody response against neutralising epitopes in the HIV-1 and HIV-2 surface glycoproteins.

2023-05-22Journal article

Open access

Hepatitis B and C in Europe: an update from the Global Burden of Disease Study 2019

Publication . Cortesi, Paolo Angelo; Fornari, Carla; Conti, Sara; Antonazzo, Ippazio Cosimo; FERRARA, Pietro; Ahmed, Ayman; Palladino, Claudia; Taveira, Nuno; GBD 2019 Europe Hepatitis B & C Collaborators

Background In 2016, the World Health Assembly adopted the resolution to eliminate viral hepatitis by 2030. This study aims to provide an overview of the burdens of hepatitis B virus (HBV) and hepatitis C virus (HCV) in Europe and their changes from 2010 to 2019 using estimates from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019. Methods We used GBD 2019 estimates of the burden associated with HBV-related and HCV-related diseases: acute hepatitis, cirrhosis and other chronic liver diseases, and liver cancer. We report total numbers and age-standardised rates per 100 000 for mortality, prevalence, incidence, and disability-adjusted life-years (DALYs) from 2010 to 2019. For each HBV-related and HCV-related disease and each measure, we analysed temporal changes and percentage changes for the 2010–19 period. Findings In 2019, across all age groups, there were an estimated 2·08 million (95% uncertainty interval [UI] 1·66 to 2·54) incident cases of acute hepatitis B and 0·49 million (0·42 to 0·57) of hepatitis C in Europe. There were an estimated 8·24 million (7·56 to 8·88) prevalent cases of HBV-related cirrhosis and 11·87 million (9·77 to 14·41) of HCV-related cirrhosis, with 24·92 thousand (19·86 to 31·03) deaths due to HBV-related cirrhosis and 36·89 thousand (29·94 to 45·56) deaths due to HCV-related cirrhosis. Deaths were estimated at 9·00 thousand (6·88 to 11·62) due to HBV-related liver cancer and 23·07 thousand (18·95 to 27·31) due to HCV-related liver cancer. Between 2010 and 2019, the age-standardised incidence rate of acute hepatitis B decreased (–22·14% [95% UI –35·44 to –5·98]) as did its age-standardised mortality rate (–33·27% [–43·03 to –25·49]); the age-standardised prevalence rate (–20·60% [–22·09 to –19·10]) and mortality rate (–33·19% [–37·82 to –28·13]) of HBV-related cirrhosis also decreased in this time period. The age-standardised incidence rate of acute hepatitis C decreased by 3·24% (1·17 to 5·02) and its age-standardised mortality rate decreased by 35·73% (23·48 to 47·75) between 2010 and 2019; the age-standardised prevalence rate (–6·37% [–8·11 to –4·32]), incidence rate (–5·87% [–11·24 to –1·01]), and mortality rate (–11·11% [–16·54 to –5·53]) of HCV-related cirrhosis also decreased. No significant changes were observed in age-standardised rates of HBV-related and HCV-related liver cancer, although we observed a significant increase in numbers of cases of HCV-related liver cancer across all ages between 2010 and 2019 (16·41% [2·81 to 30·91] increase in prevalent cases). Substantial reductions in DALYs since 2010 were estimated for acute hepatitis B (–27·82% [–36·92 to –20·24]), acute hepatitis C (–27·07% [–15·97 to –39·34]), and HBV-related cirrhosis (–30·70% [–35·75 to –25·03]). A moderate reduction in DALYs was estimated for HCV-related cirrhosis (–6·19% [–0·19 to –12·57]). Only HCV-related liver cancer showed a significant increase in DALYs (10·37% [4·81–16·63]). Changes in age-standardised DALY rates closely resembled those observed for overall DALY counts, except for HCV-liver related cancer (–2·84% [–7·75 to 2·63]). Interpretation Although decreases in some HBV-related and HCV-related diseases were estimated between 2010 and 2019, HBV-related and HCV-related diseases are still associated with a high burden, highlighting the need for more intensive and coordinated interventions within European countries to reach the goal of elimination by 2030.

2023-09-08Journal article

Open access

Improved Triamcinolone acetonide-eluting contact lenses based on cyclodextrins and high hydrostatic pressure assisted complexation

Publication . Marto-Costa, Carolina; Toffoletto, Nadia; Salema-Oom, Madalena; Antunes, Alexandra M. M.; Pinto, Carlos A.; Saraiva, Jorge A.; Silva-Herdade, Ana S.; Alvarez-Lorenzo, Carmen; Serro, Ana

Contact lenses (CLs) constitute an advantageous platform for the topical release of corticosteroids due to their prolonged contact with the eye. However, the lipophilic nature of corticosteroids hampers CLs' ability to release therapeutic amounts. Two approaches to improve loading and release of triamcinolone acetonide (TA) from poly(2-hydroxyethyl methacrylate)-based hydrogels were investigated: adding 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) to the monomers solution before polymerization (HEMA/i-CD) and an hydrogels' post-treatment with HP-β-CD (HEMA/p-CD). The effect of HP-β-CD and sterilization by high hydrostatic pressure (HHP) on the hydrogel properties (water content, oxygen and ion permeability, roughness, transmittance, and stiffness) was evaluated. The HEMA/i-CD hydrogels had stronger affinity for TA, sustaining its release for one day. HHP sterilization promoted the formation of cyclodextrin-TA complexes within the hydrogels, improving their drug-loading capacity »60 %. Cytotoxicity and irritability tests confirmed the safety of the therapeutic CLs. TA released from the hydrogels permeated through ocular tissues ex vivo and showed anti-inflammatory activity. Finally, a previously validated mathematical model was used to estimate the ability of the TA-loaded CLs to deliver therapeutic drug concentrations to the posterior part of the eye. Overall, HP-β-CD-containing CLs are promising candidates for the topical ocular application of TA as an alternative delivery system to intraocular injections.

2024Journal article

Open access