Perspective on Adenoviruses: Epidemiology, Pathogenicity, and Gene Therapy

The evolving landscape of gene therapy for congenital haemophilia: An unprecedented, problematic but promising opportunity for worldwide clinical studies

With liver-directed gene therapy, congenital haemophilia has the potential to progress from an incurable to a phenotypically curable condition. However, the proportion of haemophilia population likely to benefit from gene therapy remains to be established. Achieving a phenotypic curative goal is presently hampered by: 1) availability of effective treatments (e.g. extended half-life products, non-factor therapies) that address major unmet needs in haemophilia; 2) key differences between hope and reality that patients undergoing gene therapy face (e.g. unknown risks and long-term follow-up, durability of the therapeutic effect, possibility of re-administering the vector), 3) lack of expertise of health care professionals (HCP) in managing/monitoring unexpected side effects in patients, and 4) lack of expertise of HCP in advising payers on key issues for cost-effectiveness analyses of gene therapy (e.g., eligibility criteria, predictability of response, unknown risks, long-term complications). There is also uncertainty about the possibility to absorb the cost of the "one-time, one-dose cure" by payers that are used to different payment models. An active partnership between regulators, payers, patients and health care professionals is key to identify patient sub-populations that might benefit the most from gene therapy, and to align the interests of patients (needing effective disease correction and improved quality of life) and pharma companies (reluctant to lose the profitability of lifelong repeated treatments). Educational programs will provide the healthcare chain with information on the strategy that is expected to transform morbidity and mortality patterns and how it should be regarded as part of the future therapeutic options in haemophilia.

Prospects of Replication-Deficient Adenovirus Based Vaccine Development against SARS-CoV-2

The current appearance of the new SARS coronavirus 2 (SARS-CoV-2) and it quickly spreading across the world poses a global health emergency. The serious outbreak position is affecting people worldwide and requires rapid measures to be taken by healthcare systems and governments. Vaccinations represent the most effective strategy to prevent the epidemic of the virus and to further reduce morbidity and mortality with long-lasting effects. Nevertheless, currently there are no licensed vaccines for the novel coronaviruses. Researchers and clinicians from all over the world are advancing the development of a vaccine against novel human SARS-CoV-2 using various approaches. Herein, we aim to present and discuss the progress and prospects in the field of vaccine research towards SARS-CoV-2 using adenovirus (AdV) replication deficient-based strategies, with a comprehension that may support research and combat this recent world health emergency.

The cell-penetrating YopM protein-functionalized quantum dot-plasmid DNA conjugate as a novel gene delivery vector

Non-viral gene delivery systems have great potential for safe and efficient gene therapy, while inefficient cellular and nuclear uptake remain as the major hurdles. Novel approaches are needed to enhance the transfection efficiency of non-viral vectors. In accordance with this need, the objective of this study was to construct a non-viral vector that could achieve gene delivery without using additional lipid-based transfection agent. We aimed to impart self-delivery property to a non-viral vector by using the cell and nucleus penetrating properties of YopM proteins from the three Yersinia spp. (Y. pestis, Y. enterocolotica and Y. pseudotuberculosis). Plasmid DNA (pDNA) encoding green fluorescent protein (GFP) was labeled with quantum dots (QDs) via peptide-nucleic acid (PNA) recognition site. Recombinant YopM protein was then attached to the conjugate via a second PNA recognition site. The YopM ̶ QDs ̶ pDNA conjugate was transfected into HeLa cells without using additional transfection reagent. All three conjugates produced GFP fluorescence, indicating that the plasmid was successfully delivered to the nucleus. As control, naked pDNA was transfected into the cells by using a commercial transfection reagent. The Y. pseudotuberculosis YopM-functionalized conjugate achieved the highest GFP expression, compared to other two YopM proteins and the transfection reagent. To the best of our knowledge, YopM protein was used for the first time in a non-viral gene delivery vector.

First-in-Human, First-in-Child Trial of Autologous MSCs Carrying the Oncolytic Virus Icovir-5 in Patients with Advanced Tumors

We present here the results of a first-in-human, first-in-child trial for patients with relapsed/refractory solid tumors using Celyvir, an advanced therapy medicine that combines autologous mesenchymal stem cells (MSCs) carrying an oncolytic adenovirus. Celyvir was manufactured from a bone marrow aspirate and then given intravenously. Patients received weekly infusions for 6 weeks at a dose of 2 × 10⁶ cells/kg (children) or 0.5-1 × 10⁶ cells/kg (adults), 2 × 10⁴ viral particles per cell. Fifteen pediatric and 19 adult patients were recruited, but 18 were screen failures, mainly because rapid disease progression before Celyvir was available. No grade 2-5 toxicities were reported. Adenoviral replication detected by PCR was found in all but 2 pediatric patient and in none of the adult ones. Absolute numbers of circulating leukocytes suffered minor changes along therapy, but some subsets showed differences comparing the pediatric versus the adult cohorts. Two patients with neuroblastoma showed disease stabilization, and one of them continued on treatment for up to 6 additional weeks. Celyvir, the combination of MSCs and oncolytic adenovirus, is safe and warrants further evaluation in a phase 2 setting. The use of MSCs may be a strategy to increase the amount of oncolytic virus administered to patients, minimizing toxicities and avoiding direct tumor injections.

Respiratory Viral Pathogens☆

Respiratory viruses are responsible for a variety of clinical syndromes including the common cold, acute otitis media, laryngitis, sinusitis, pneumonia, bronchiolitis, influenza-like illness, and exacerbations of asthma and chronic obstructive pulmonary disease. Diagnosis of respiratory viral infections is primarily clinical and is further supported by laboratory techniques such as antigen detection, serology, and nucleic acid detection. Preventive strategies are based on avoidance of risk factors and, in case of influenza, vaccination. Treatment modalities include over-the-counter and non-specific remedies along with a small number of specific antiviral medications such as the influenza neuraminidase inhibitors or palivizumab against respiratory syncytial virus.

Alcohol Exposure Impacts the Composition of HeLa-Derived Extracellular Vesicles

Extracellular vesicles are nanosized vesicles that are under intense investigation for their role in intercellular communication. Extracellular vesicles have begun to be examined for their role in disease protection and their role as disease biomarkers and/or vaccine agents. The goal of this study was to investigate the effects of alcohol exposure on the biogenesis and composition of extracellular vesicles derived from the cervical cancer line, HeLa. The HeLa cells were cultured in exosome-free media and were either mock-treated (control) or treated with 50 mM or 100 mM of alcohol for 24 h and 48 h. Our results demonstrated that alcohol significantly impacts HeLa cell viability and exosome biogenesis/composition. Importantly, our studies demonstrate the critical role of alcohol on HeLa cells, as well as HeLa-derived extracellular vesicle biogenesis and composition. Specifically, these results indicate that alcohol alters extracellular vesicles’ packaging of heat shock proteins and apoptotic proteins. Extracellular vesicles serve as communicators for HeLa cells, as well as biomarkers for the initiation and progression of disease.