COVID-19 Vaccine Frontrunners and Their Nanotechnology Design

Tapered chiral nanoparticles as broad-spectrum thermally stable antivirals for SARS-CoV-2 variants

The incessant mutations of viruses, variable immune responses, and likely emergence of new viral threats necessitate multiple approaches to novel antiviral therapeutics. Furthermore, the new antiviral agents should have broad-spectrum activity and be environmentally stable. Here, we show that biocompatible tapered CuS nanoparticles (NPs) efficiently agglutinate coronaviruses with binding affinity dependent on the chirality of surface ligands and particle shape. L-penicillamine-stabilized NPs with left-handed curved apexes display half-maximal inhibitory concentrations (IC50) as low as 0.66 pM (1.4 ng/mL) and 0.57 pM (1.2 ng/mL) for pseudo-type SARS-CoV-2 viruses and wild-type Wuhan-1 SARS-CoV-2 viruses, respectively, which are about 1,100 times lower than those for antibodies (0.73 nM). Benefiting from strong NPs-protein interactions, the same particles are also effective against other strains of coronaviruses, such as HCoV-HKU1, HCoV-OC43, HCoV-NL63, and SARS-CoV-2 Omicron variants with IC50 values below 10 pM (21.8 ng/mL). Considering rapid response to outbreaks, exposure to elevated temperatures causes no change in the antiviral activity of NPs while antibodies are completely deactivated. Testing in mice indicates that the chirality-optimized NPs can serve as thermally stable analogs of antiviral biologics complementing the current spectrum of treatments.

Expanded specific T cells to hypomutated regions of the SARS-CoV-2 using mRNA electroporated antigen-presenting cells

The COVID-19 pandemic has caused about seven million deaths worldwide. Preventative vaccines have been developed including Spike gp mRNA-based vaccines that provide protection to immunocompetent patients. However, patients with primary immunodeficiencies, patients with cancer, or hematopoietic stem cell transplant recipients are not able to mount robust immune responses against current vaccine approaches. We propose to target structural SARS-CoV-2 antigens (i.e., Spike gp, Membrane, Nucleocapsid, and Envelope) using circulating human antigen-presenting cells electroporated with full length SARS-CoV-2 structural protein-encoding mRNAs to activate and expand specific T cells. Based on the Th1-type cytokine and cytolytic enzyme secretion upon antigen rechallenge, we were able to generate SARS-CoV-2 specific T cells in up to 70% of unexposed unvaccinated healthy donors (HDs) after 3 subsequent stimulations and in 100% of recovered patients (RPs) after 2 stimulations. By means of SARS-CoV-2 specific TCRβ repertoire analysis, T cells specific to Spike gp-derived hypomutated regions were identified in HDs and RPs despite viral genomic evolution. Hence, we demonstrated that SARS-CoV-2 mRNA-loaded antigen-presenting cells are effective activating and expanding COVID19-specific T cells. This approach represents an alternative to patients who are not able to mount adaptive immune responses to current COVID-19 vaccines with potential protection across new variants that have conserved genetic regions.

Modularized viromimetic polymer nanoparticle vaccines (VPNVaxs) to elicit durable and effective humoral immune responses

Virus-like particle (VLP) vaccines had shown great potential during the COVID-19 pandemic, and was thought to be the next generation of antiviral vaccine technology due to viromimetic structures. However, the time-consuming and complicated processes in establishing a current recombinant-protein-based VLP vaccine has limited its quick launch to the out-bursting pandemic. To simplify and optimize VLP vaccine design, we herein report a kind of viromimetic polymer nanoparticle vaccine (VPNVax), with subunit receptor-binding domain (RBD) proteins conjugated to the surface of polyethylene glycol-b-polylactic acid (PEG-b-PLA) nanoparticles for vaccination against SARS-CoV-2. The preparation of VPNVax based on synthetic polymer particle and chemical post-conjugation makes it possible to rapidly replace the antigens and construct matched vaccines at the emergence of different viruses. Using this modular preparation system, we identified that VPNVax with surface protein coverage of 20%-25% had the best immunostimulatory activity, which could keep high levels of specific antibody titers over 5 months and induce virus neutralizing activity when combined with an aluminum adjuvant. Moreover, the polymer nano-vectors could be armed with more immune-adjuvant functions by loading immunostimulant agents or chemical chirality design. This VPNVax platform provides a novel kind of rapidly producing and efficient vaccine against different variants of SARS-CoV-2 as well as other viral pandemics.

Expertise as a Response to Limited Multilateralism: The Case of South Korea's Vaccine Procurement Task Force for COVID-19 Vaccines amid Unequal Access via the COVAX Facility

This study investigates South Korea's trials and errors in procuring COVID-19 vaccines from abroad, amid the limitations of a multilateral scheme for global provision through the COVID-19 Vaccines Global Access (COVAX) program via the World Health Organization (WHO) and the discussions on COVID-19 vaccine patent waivers at the World Trade Organization. Using the framework of "self-help" in the international system and country categorization to explicate country behaviors by state-business relations and expertise to explain South Korea's COVID-19 vaccine procurement process, this study argues that in the absence of a global mechanism that guarantees adequate and timely vaccine provision, countries are left to the sole option of depending on their own capabilities: expertise, budget, and policy planning by consolidating public and private capacities to acquire vaccines for the public. To support the argument, an in-depth case investigation of South Korea's Vaccine Procurement Task Force is presented. The case study focuses on the policy assessment of critical elements in South Korea's vaccine procurement and rollout on facing obstacles to sufficient procurement through COVAX: decision-making impacting the timing and dosage of procurement, diplomatic and business channels to sign bilateral contracts, setup of a smart-factory vaccination hub, and indigenous vaccine development for WHO approval.

Protein subunit vaccines: Promising frontiers against COVID-19

The emergence of COVID-19 has posed an unprecedented global health crisis, challenging the healthcare systems worldwide. Amidst the rapid development of several vaccine formulations, protein subunit vaccines have emerged as a promising approach. This article provides an in-depth evaluation of the role of protein subunit vaccines in the management of COVID-19. Leveraging viral protein fragments, particularly the spike protein from SARS-CoV-2, these vaccines elicit a targeted immune response without the risk of inducing disease. Notably, the robust safety profile of protein subunit vaccines makes them a compelling candidate in the management of COVID-19. Various innovative approaches, including reverse vaccinology, virus like particles, and recombinant modifications are incorporated to develop protein subunit vaccines. In addition, the utilization of advanced manufacturing techniques facilitates large-scale production, ensuring widespread distribution. Despite these advancements, challenges persist, such as the requirement for cold-chain storage and the necessity for booster doses. This article evaluates the formulation and applications of protein subunit vaccines, providing a comprehensive overview of their clinical development and approvals in the context of COVID-19. By addressing the current status and challenges, this review aims to contribute to the ongoing discourse on optimizing protein subunit vaccines for effective pandemic control.

Thyroid Inflammation and Immunity During the COVID-19 Pandemic: A Comprehensive Review and Case Study

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to the development of various vaccines. Reports have emerged suggesting a possible association between SARS-CoV-2 vaccination and the onset of thyroid diseases. This review explores the clinical aspects of thyroid disorders following SARS-CoV-2 vaccination, including a case report of a patient with concomitant subacute thyroiditis (SAT) and Graves' disease (GD) with blocking thyrotropin receptor autoantibodies (TSH-R-Ab) following SARS-CoV-2 vaccination. SAT, characterized by transient inflammation of the thyroid gland, has been reported after SARS-CoV-2 vaccination. GD, an autoimmune hyperthyroidism, has also been observed post-vaccination, often with stimulating TSH-R-Ab. Graves' orbitopathy (GO) has been associated with SARS-CoV-2 vaccination in patients with a history of immune thyroid disease. The unique case underscores a very rare thyroid condition of functional hypothyroidism in possible relation to SARS-CoV-2 vaccination and the usefulness of functional analysis of TSH-R-Ab that can provide valuable insights into disease pathogenesis and help to guide treatment. This review highlights the need for continued monitoring and awareness of potential thyroid-related complications following SARS-CoV-2 vaccination.

Effects of the glycosylation of the receptor binding domain (RBD dimer)-based Covid-19 vaccine (ZF2001) on its humoral immunogenicity and immunoreactivity

The SARS-CoV-2 spike protein receptor-binding domain (RBD), which is a key target for the development of SARS-CoV-2 neutralizing antibodies and vaccines, mediates the binding of the host receptor angiotensin-converting enzyme 2 (ACE2). However, the high heterogeneity of RBD glycoforms may lead to an incomplete neutralization effect and impact the immunogenicity of RBD-based vaccines (Ye et al., 2021). Here, our data suggested that the glycosylation significantly affected the humoral immunogenicity and immunoreactivity of the RBD-dimer-based Covid-19 vaccine (ZF2001) (Yang et al., 2021). Several deglycosylated types of ZF2001 (with sialic acid removed (ZF2001-ΔSA), sialic acid & O-glycans removed (ZF2001-ΔSA&O), N-glycans removed (ZF2001-ΔN), N- & O-glycans removed (ZF2001-ΔN&O)) were obtained by treatment with glycosidases. The binding affinity between deglycosylated types of ZF2001 and ACE2 was slightly weakened and that between deglycosylated types of ZF2001 and several monoclonal antibodies (mAbs) were also changed compared with ZF2001. The results of pseudovirus neutralization assay and binding affinity assay of all ZF2001 types revealed that the antigens with complex glycosylation had better humoral immunogenicity and immunoreactivity. Molecular dynamics simulation indicated that the more complex glycosylation of RBD corresponded to more hydrogen bonds formed between helper T-cell epitopes of RBD and major histocompatibility complex II (MHC-II). In summary, these results demonstrated that the glycosylation of RBD affects antigen presentation, humoral immunogenicity and immunoreactivity, which may be an important consideration for vaccine design and production technology.

Responsive Nucleic Acid-Based Organosilica Nanoparticles

The development of smart nanoparticles (NPs) that encode responsive features in the structural framework promises to extend the applications of NP-based drugs, vaccines, and diagnostic tools. New nanocarriers would ideally consist of a minimal number of biocompatible components and exhibit multiresponsive behavior to specific biomolecules, but progress is limited by the difficulty of synthesizing suitable building blocks. Through a nature-inspired approach that combines the programmability of nucleic acid interactions and sol-gel chemistry, we report the incorporation of synthetic nucleic acids and analogs, as constitutive components, into organosilica NPs. We prepared different nanomaterials containing single-stranded nucleic acids that are covalently embedded in the silica network. Through the incorporation of functional nucleic acids into the organosilica framework, the particles respond to various biological, physical, and chemical inputs, resulting in detectable physicochemical changes. The one-step bottom-up approach used to prepare organosilica NPs provides multifunctional systems that combine the tunability of oligonucleotides with the stiffness, low cost, and biocompatibility of silica for different applications ranging from drug delivery to sensing.

Rapid Internalization of Nanoparticles by Human Cells at the Single Particle Level

Nanoparticle uptake by cells has been studied for applications both in nanomedicine and in nanosafety. While the majority of studies have focused on the biological mechanisms underlying particle internalization, less attention has been given to questions of a more quantitative nature, such as how many nanoparticles enter cells and how rapidly they do so. To address this, we exposed human embryonic kidney cells to 40-200 nm carboxylated polystyrene nanoparticles and the particles were observed by live-cell confocal and super-resolution stimulated emission depletion fluorescence microscopy. How long a particle remained at the cell membrane after adsorbing onto it was monitored, distinguishing whether the particle ultimately desorbed again or was internalized by the cell. We found that the majority of particles desorb, but interestingly, most of the particles that are internalized do so within seconds, independently of particle size. As this is faster than typical endocytic mechanisms, we interpret this observation as the particles entering via an endocytic event that is already taking place (as opposed to directly triggering their own uptake) or possibly via an as yet uncharacterized endocytic route. Aside from the rapidly internalizing particles, a minority of particles remain at the membrane for tens of seconds to minutes before desorbing or being internalized. We also followed particles after cell internalization, observing particles that appeared to exit the cell, sometimes as rapidly as within tens of seconds. Overall, our results provide quantitative information about nanoparticle cell internalization times and early trafficking.

Class switch towards spike protein-specific IgG4 antibodies after SARS-CoV-2 mRNA vaccination depends on prior infection history

Vaccinations against SARS-CoV-2 reduce the risk of developing serious COVID-19 disease. Monitoring spike-specific IgG subclass levels after vaccinations may provide additional information on SARS-CoV-2 specific humoral immune response. Here, we examined the presence and levels of spike-specific IgG antibody subclasses in health-care coworkers vaccinated with vector- (Sputnik, AstraZeneca) or mRNA-based (Pfizer-BioNTech, Moderna) vaccines against SARS-CoV-2 and in unvaccinated COVID-19 patients. We found that vector-based vaccines elicited lower total spike-specific IgG levels than mRNA vaccines. The pattern of spike-specific IgG subclasses in individuals infected before mRNA vaccinations resembled that of vector-vaccinated subjects or unvaccinated COVID-19 patients. However, the pattern of mRNA-vaccinated individuals without SARS-CoV-2 preinfection showed a markedly different pattern. In addition to IgG1 and IgG3 subclasses presented in all groups, a switch towards distal IgG subclasses (spike-specific IgG4 and IgG2) appeared almost exclusively in individuals who received only mRNA vaccines or were infected after mRNA vaccinations. In these subjects, the magnitude of the spike-specific IgG4 response was comparable to that of the spike-specific IgG1 response. These data suggest that the priming of the immune system either by natural SARS-CoV-2 infection or by vector- or mRNA-based vaccinations has an important impact on the characteristics of the developed specific humoral immunity.

An update on vaccine status and the role of nanomedicine against SARS-CoV-2: A narrative review

Background and Aims

Coronavirus disease 2019 (COVID-19), caused by the SARS-CoV-2 novel coronavirus, is a highly communicable disease that gave rise to the ongoing pandemic. Despite prompt action across many laboratories in many countries, effective management of this disease is still out of reach. The focus of this review is to describe various vaccination approaches and nanomedicine-based delivery systems against COVID-19.

Methods

The articles included in this study were searched and added from different electronic databases, including PubMed, Scopus, Cochrane, Embase, and preprint databases.

Results

Mass immunization with vaccines is currently at the forefront of COVID-19 infection control. Such vaccines are live attenuated vaccines, inactivated vaccines, nucleic acid-based vaccines, protein subunit vaccines, viral-vector vaccines, and virus-like particle platforms. However, many promising avenues are currently being explored in laboratory and clinical settings, including treatment options, prevention, diagnosis, and management of the disease. Soft nanoparticles like lipid nanoparticles (solid lipid nanoparticles (SLNPs), liposomes, nanostructured lipid carriers, nanoemulsions, and protein nanoparticles play an essential role in nanomedicine. Because of their unique and excellent properties, nanomedicines have potential applications in treating COVID-19 disease.

Conclusions

This review work provides an overview of the therapeutic aspects of COVID-19, including vaccination and the role of nanomedicines in the diagnosis, treatment, and prevention of COVID-19.

Surfactant-Tunable Nanoparticle Assembly via a Template-Directed Strategy

Nanoparticle (NP) self-assembly from suspension evaporation has been a topic of interest in recent times to fabricate a solid-state structure with diverse functions. We present a simple and facile evaporation-induced strategy for the formation of NP arrays on a flat substrate utilizing a template-directed sandwich system. The lithographic features assist the assembly of the typical nanoparticles (NPs), including SiO₂, QDs@PS FMs, and QDs, on the top into circle, stripe, triangle, or square geometries with a fixed width of 2 μm. Additionally, an anionic surfactant, sodium dodecyl sulfonate (SDS), is incorporated into a negatively charged, hydrophilic SiO₂ dispersion to govern the aggregation and self-assembly of NPs, fine tuning the morphologies of the residual structures on the substrate. SDS is attributed to modify the nature of SiO₂ NPs to be hydrophobic, increase the hydrophobic attraction, dominating particle-particle and particle-interface interactions, and strengthen the particle-particle repulsive electrostatic force that results in the reduction of SiO₂ NPs trapped in the separated colloidal suspension drop. Thus, using the SDS surfactant with the concentration ranging from 0 to 1 wt %, the obtained well-ordered SiO₂ NP pattern packing on the substrate varies from six layers to one layer.

Clinical Delivery of Circular RNA: Lessons Learned from RNA Drug Development

Circular RNAs (circRNA) represent a distinct class of covalently closed-loop RNA molecules, which play diverse roles in regulating biological processes and disease states. The enhanced stability of synthetic circRNAs compared to their linear counterparts has recently garnered considerable research interest, paving the way for new therapeutic applications. While clinical circRNA technology is still in its early stages, significant advancements in mRNA technology offer valuable insights into its potential future applications. Two primary obstacles that must be addressed are the development of efficient production methods and the optimization of delivery systems. To expedite progress in this area, this review aims to provide an overview of the current state of knowledge on circRNA structure and function, outline recent techniques for synthesizing circRNAs, highlight key delivery strategies and applications, and discuss the current challenges and future prospects in the field of circRNA-based therapeutics.

COVID-19 vaccines based on viral nanoparticles displaying a conserved B-cell epitope show potent immunogenicity and a long-lasting antibody response

The COVID-19 pandemic caused by SARS-CoV-2 sparked intensive research into the development of effective vaccines, 50 of which have been approved thus far, including the novel mRNA-based vaccines developed by Pfizer and Moderna. Although limiting the severity of the disease, the mRNA-based vaccines presented drawbacks, such as the cold chain requirement. Moreover, antibody levels generated by these vaccines decline significantly after 6 months. These vaccines deliver mRNA encoding the full-length spike (S) glycoprotein of SARS-CoV-2, but must be updated as new strains and variants of concern emerge, creating a demand for adjusted formulations and booster campaigns. To overcome these challenges, we have developed COVID-19 vaccine candidates based on the highly conserved SARS CoV-2, 809-826 B-cell peptide epitope (denoted 826) conjugated to cowpea mosaic virus (CPMV) nanoparticles and bacteriophage Qβ virus-like particles, both platforms have exceptional thermal stability and facilitate epitope delivery with inbuilt adjuvant activity. We evaluated two administration methods: subcutaneous injection and an implantable polymeric scaffold. Mice received a prime-boost regimen of 100 μg per dose (2 weeks apart) or a single dose of 200 μg administered as a liquid formulation, or a polymer implant. Antibody titers were evaluated longitudinally over 50 weeks. The vaccine candidates generally elicited an early Th2-biased immune response, which stimulates the production of SARS-CoV-2 neutralizing antibodies, followed by a switch to a Th1-biased response for most formulations. Exceptionally, vaccine candidate 826-CPMV (administered as prime-boost, soluble injection) elicited a balanced Th1/Th2 immune response, which is necessary to prevent pulmonary immunopathology associated with Th2 bias extremes. While the Qβ-based vaccine elicited overall higher antibody titers, the CPMV-induced antibodies had higher avidity. Regardless of the administration route and formulation, our vaccine candidates maintained high antibody titers for more than 50 weeks, confirming a potent and durable immune response against SARS-CoV-2 even after a single dose.

COVID-19 Anti-Vaccine Sentiments in Malaysia: Narratives of Comments from Facebook Post

The anti-vaccination movement was an ongoing issue in Malaysia, a Muslim-majority country, even before the COVID-19 pandemic. It is unclear whether the introduction of new COVID-19 vaccines would similarly provoke anti-vaccine sentiments. This study analyzed COVID-19 anti-vaccine sentiments in the Malaysian community. Anti-vaccine comments from Facebook page posts were extracted. The qualitative software QSR-NVivo 10 was used to manage, code and analyze the data. The fast-track COVID-19 vaccine evoked the fear of unknown long-term effects, safety, effectiveness and the duration of protection. The halal status of the COVID-19 vaccines is important. Although it is permissible to use vaccines that are not certified halal under the state of darurah (emergency), there was doubt that the current state has reached the stage of darurah that warrants the use of vaccines. COVID-19 vaccine microchip conspiracy theories were raised. COVID-19 is viewed as only severe for vulnerable populations, and hence vaccination is not needed for the healthy. There were opinions that coronavirus treatments would be more beneficial than vaccination. The anti-COVID-19 vaccine sentiments uncovered in this study provide important insights for the formulation of public health messages to instill confidence in new COVID-19 vaccines. Despite the pandemic being nearly over and many people worldwide having received COVID-19 vaccines, the findings provide important insight into potential issues regarding the introduction of new vaccines in the event of future pandemics.

Smuggling on the Nanoscale-Fusogenic Liposomes Enable Efficient RNA-Transfer with Negligible Immune Response In Vitro and In Vivo

The efficient and biocompatible transfer of nucleic acids into mammalian cells for research applications or medical purposes is a long-standing, challenging task. Viral transduction is the most efficient transfer system, but often entails high safety levels for research and potential health impairments for patients in medical applications. Lipo- or polyplexes are commonly used transfer systems but result in comparably low transfer efficiencies. Moreover, inflammatory responses caused by cytotoxic side effects were reported for these transfer methods. Often accountable for these effects are various recognition mechanisms for transferred nucleic acids. Using commercially available fusogenic liposomes (Fuse-It-mRNA), we established highly efficient and fully biocompatible transfer of RNA molecules for in vitro as well as in vivo applications. We demonstrated bypassing of endosomal uptake routes and, therefore, of pattern recognition receptors that recognize nucleic acids with high efficiency. This may underlie the observed almost complete abolishment of inflammatory cytokine responses. RNA transfer experiments into zebrafish embryos and adult animals fully confirmed the functional mechanism and the wide range of applications from single cells to organisms.

COVID-19 mRNA Vaccines: The Molecular Basis of Some Adverse Events

Each injection of any known vaccine results in a strong expression of pro-inflammatory cytokines. This is the result of the innate immune system activation, without which no adaptive response to the injection of vaccines is possible. Unfortunately, the degree of inflammation produced by COVID-19 mRNA vaccines is variable, probably depending on genetic background and previous immune experiences, which through epigenetic modifications could have made the innate immune system of each individual tolerant or reactive to subsequent immune stimulations.We hypothesize that we can move from a limited pro-inflammatory condition to conditions of increasing expression of pro-inflammatory cytokines that can culminate in multisystem hyperinflammatory syndromes following COVID-19 mRNA vaccines (MIS-V). We have graphically represented this idea in a hypothetical inflammatory pyramid (IP) and we have correlated the time factor to the degree of inflammation produced after the injection of vaccines. Furthermore, we have placed the clinical manifestations within this hypothetical IP, correlating them to the degree of inflammation produced. Surprisingly, excluding the possible presence of an early MIS-V, the time factor and the complexity of clinical manifestations are correlated to the increasing degree of inflammation: symptoms, heart disease and syndromes (MIS-V).

Generalized Eosinophilia Following Moderna COVID-19 Vaccine Administration: A Case Report

Coronavirus disease 19 (COVID-19) vaccination is considered an important part in improving health outcomes globally. While various adverse events following vaccination against COVID-19 have been reported, eosinophilic diseases have rarely been documented in the literature and are poorly understood. Although vaccination is lauded as being “safe,” it has become apparent that adverse reactions related to the vaccines can have detrimental health effects for certain individuals. We present a case of a death related to multiple severe preexisting comorbidities, complicated by new-onset gastrointestinal complaints which were temporally associated with recent COVID-19 vaccination and did not subside, but worsened prior to death. Autopsy revealed evidence of eosinophilic enteritis, associated with ascites, as well as eosinophilic inflammation elsewhere, including the lungs and heart. Histological examination revealed abundant eosinophils in tissues, including the small intestines, epicardium, and lungs. Whether or not the eosinophilic inflammatory process was caused by the recent vaccination cannot be stated with certainty; however, the temporal association between vaccination, symptom onset/progression, and death, and the literature which suggests a possible association between coronavirus vaccination and eosinophilic reactions leads to the conclusion that this death might have been related to an adverse reaction to COVID-19 vaccination.

Supramolecular Polyphenol-DNA Microparticles for In Vivo Adjuvant and Antigen Co-Delivery and Immune Stimulation

DNA-based materials have attracted interest due to the tunable structure and encoded biological functionality of nucleic acids. A simple and general approach to synthesize DNA-based materials with fine control over morphology and bioactivity is important to expand their applications. Here, we report the synthesis of DNA-based particles via the supramolecular assembly of tannic acid (TA) and DNA. Uniform particles with different morphologies are obtained using a variety of DNA building blocks. The particles enable the co-delivery of cytosine-guanine adjuvant sequences and the antigen ovalbumin in model cells. Intramuscular injection of the particles in mice induces antigen-specific antibody production and T cell responses with no apparent toxicity. Protein expression in cells is shown using capsules assembled from TA and plasmid DNA. This work highlights the potential of TA as a universal material for directing the supramolecular assembly of DNA into gene and vaccine delivery platforms.

A mini review for lipid-based nanovaccines: from their design to their applications

Nanovaccines have shown to be effective, and this is the reason they are preferred than conventional vaccines. The scope of this review is to describe the role, mechanisms, and advantages of nano vaccines based on lipids, and present the most important types, their physicochemical characteristics, as well as their challenges. The most important categories of lipid nano-vaccines are liposomal nano vaccines and (virus-lipid nanoparticles (NPs)/virosomes. Examples of vaccine formulations from each category are presented and analyzed below, focusing on their structure and physicochemical characteristics. In all cases, a nanoscale platform is used, enriched with adjuvants, antigens, and other helping agents to trigger immune response process and achieve cell targeting, and eventually immunity against the desired disease. The exact mechanism of action of each vaccine is not always completely known or understood. Physicochemical characteristics, such as particle size, morphology/shape, and zeta potential are also mentioned as they seem to affect the properties and mechanism of action of the vaccine formulation.

Gold Complexes in Anticancer Therapy: From New Design Principles to Particle-Based Delivery Systems

The discovery of the medicinal properties of gold complexes has fuelled the design and synthesis of new anticancer metallodrugs, which have received special attention due to their unique modes of action. Current research in the development of gold compounds with therapeutic properties is predominantly focused on the molecular design of drug leads with superior pharmacological activities, e.g., by introducing targeting features. Moreover, intensive research aims at improving the physicochemical properties of gold compounds, such as chemical stability and solubility in the physiological environment. In this regard, the encapsulation of gold compounds in nanocarriers or their chemical grafting onto targeted delivery vectors could lead to new nanomedicines that eventually reach clinical applications. Herein, we provide an overview of the state-of-the-art progress of gold anticancer compounds, andmore importantly we thoroughly revise the development of nanoparticle-based delivery systems for gold chemotherapeutics.

mRNA-Based Vaccine for COVID-19: They Are New but Not Unknown!

mRNA vaccines take advantage of the mechanism that our cells use to produce proteins. Our cells produce proteins based on the knowledge contained in our DNA; each gene encodes a unique protein. The genetic information is essential, but cells cannot use it until mRNA molecules convert it into instructions for producing specific proteins. mRNA vaccinations provide ready-to-use mRNA instructions for constructing a specific protein. BNT162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna) both are newly approved mRNA-based COVID-19 vaccines that have shown excellent protection and efficacy. In total, there are five more mRNA-based vaccine candidates for COVID-19 under different phases of clinical development. This review is specifically focused on mRNA-based vaccines for COVID-19 covering its development, mechanism, and clinical aspects.

Current state of, prospects for, and obstacles to mRNA vaccine development

Given their superior efficacy, rapid engineering, low-cost manufacturing, and safe delivery prospects, mRNA vaccines offer an intriguing alternative to conventional vaccination technologies. Several mRNA vaccine platforms targeting infectious diseases and various types of cancer have exhibited beneficial results both in vivo and in vitro. Issues related to mRNA stability and immunogenicity have been addressed. Current mRNA vaccines can generate robust immune responses, without being constrained by the major histocompatibility complex (MHC) haplotype of the recipient. Given that mRNA vaccinations are the only transient genetic information carriers, they are also safe. In this review, we provide an update and overview on mRNA vaccines, including their current state, and the problems that have prevented them from being used in more general therapeutic ways.

Advancement in COVID-19 detection using nanomaterial-based biosensors

Coronavirus disease 2019 (COVID-19) pandemic has exemplified how viral growth and transmission are a significant threat to global biosecurity. The early detection and treatment of viral infections is the top priority to prevent fresh waves and control the pandemic. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been identified through several conventional molecular methodologies that are time-consuming and require high-skill labor, apparatus, and biochemical reagents but have a low detection accuracy. These bottlenecks hamper conventional methods from resolving the COVID-19 emergency. However, interdisciplinary advances in nanomaterials and biotechnology, such as nanomaterials-based biosensors, have opened new avenues for rapid and ultrasensitive detection of pathogens in the field of healthcare. Many updated nanomaterials-based biosensors, namely electrochemical, field-effect transistor, plasmonic, and colorimetric biosensors, employ nucleic acid and antigen-antibody interactions for SARS-CoV-2 detection in a highly efficient, reliable, sensitive, and rapid manner. This systematic review summarizes the mechanisms and characteristics of nanomaterials-based biosensors for SARS-CoV-2 detection. Moreover, continuing challenges and emerging trends in biosensor development are also discussed.

A Literature Review on SARS-CoV-2 and Other Viruses in Thyroid Disorders: Environmental Triggers or No-Guilty Bystanders?

A growing number of findings indicate a relationship between COVID-19 infection and thyroid dysfunction. This association is also strengthened by knowledge on the potential of viral infections to trigger thyroid disorders, although the exact underlying pathogenetic process remains to be elucidated. This review aimed to describe the available data regarding the possible role of infectious agents, and in particular of SARS-CoV-2, in the development of thyroid disorders, summarizing the proposed mechanisms and levels of evidence (epidemiological, serological or direct presence of the viruses in the thyroid gland) by which the infection could be responsible for thyroid abnormalities/diseases. Novel data on the association and mechanisms involved between SARS-CoV-2 vaccines and thyroid diseases are also discussed. While demonstrating a clear causal link is challenging, numerous clues at molecular and cellular levels and the large amount of epidemiological data suggest the existence of this relationship. Further studies should be taken to further investigate the true nature and strength of this association, to help in planning future preventive and therapeutic strategies for more personal and targeted care with attention to the underlying causes of thyroid dysfunction.

Subacute Thyroiditis Developing Within 2 Days of Vaccination Against COVID-19 with BNT162b2 mRNA

A 32-year-old woman presented to the outpatient clinic with persistent fever, anterior neck pain, and palpitations over the past week which developed 2 days after she had received the first dose of the Pfizer/BioNTech SARS-CoV-2 mRNA vaccine. On examination, the patient's heart rate was 140 beats per minute and the thyroid gland was tender on palpation. Laboratory studies showed a low serum TSH level with elevated free thyroxine. Thyroid ultrasound revealed low-echoic lesions compatible with the site of tenderness. The patient was diagnosed with subacute thyroiditis and treatment was initiated with acetaminophen and propranolol, which resulted in symptom resolution within 2 weeks. Clinicians should be aware that subacute thyroiditis may occur within a few days following COVID-19 vaccination, especially in patients with anterior cervical pain with no significant abnormal pharyngeal findings and/or severe palpitations, because differentiating them from early non-specific adverse reactions can be challenging.

LEARNING POINTS

Cases of subacute thyroiditis after vaccination, including against COVID-19, have been increasingly reported.Subacute thyroiditis should be considered in patients with anterior cervical pain with no significant abnormal pharyngeal findings and/or severe palpitations after COVID-19 vaccination because these can be diagnostic clues.It is important to note that this condition can occur as early as a few days after vaccination, in order to avoid diagnostic pitfalls.

Development of a Modular NTA:His Tag Viral Vaccine for Co-delivery of Antigen and Adjuvant

The SARS-CoV-2 pandemic has highlighted the need for vaccines that are effective, but quickly produced. Of note, vaccines with plug-and-play capabilities that co-deliver antigen and adjuvant to the same cell have shown remarkable success. Our approach of utilizing a nitrilotriacetic acid (NTA) histidine (His)-tag chemistry with viral adjuvants incorporates both of these characteristics: plug-and-play and co-delivery. We specifically utilize the cowpea mosaic virus (CPMV) and the virus-like particles from bacteriophage Qβ as adjuvants and bind the model antigen ovalbumin (OVA). Successful binding of the antigen to the adjuvant/carrier was verified by SDS-PAGE, western blot, and ELISA. Immunization in C57BL/6J mice demonstrates that with Qβ - but not CPMV - there is an improved antibody response against the target antigen using the Qβ-NiNTA:His-OVA versus a simple admixture of antigen and adjuvant. Antibody isotyping also shows that formulation of the vaccines can alter T helper biases; while the Qβ-NiNTA:His-OVA particle produces a balanced Th1/Th2 bias the admixture was strongly Th2. In a mouse model of B16F10-OVA, we further demonstrate improved survival and slower tumor growth in the vaccine groups compared to controls. The NiNTA:His chemistry demonstrates potential for rapid development of future generation vaccines enabling plug-and-play capabilities with effectiveness boosted by co-delivery to the same cell.

Minimizing Viral Transmission in COVID-19 Like Pandemics: Technologies, Challenges, and Opportunities

Coronavirus (COVID-19) pandemic has incurred huge loss to human lives throughout the world. Scientists, researchers, and doctors are trying their best to develop and distribute the COVID-19 vaccine throughout the world at the earliest. In current circumstances, different tracking systems are utilized to control or stop the spread of the virus till the whole population of the world gets vaccinated. To track and trace patients in COVID-19 like pandemics, various tracking systems based on different technologies are discussed and compared in this paper. These technologies include, cellular, cyber, satellite-based radio navigation and low range wireless technologies. The main aim of this paper is to conduct a comprehensive survey that can overview all such tracking systems, which are used in minimizing the spread of COVID-19 like pandemics. This paper also highlights the shortcoming of each tracking systems and suggests new mechanisms to overcome such limitations. In addition, the authors propose some futuristic approaches to track patients in prospective pandemics, based on artificial intelligence and big data analysis. Potential research directions, challenges, and the introduction of next-generation tracking systems for minimizing the spread of prospective pandemics, are also discussed at the end.

Bacterial expression systems based on Tymovirus-like particles for the presentation of vaccine antigens

Virus-like particles (VLPs) are virus-derived artificial nanostructures that resemble a native virus-stimulating immune system through highly repetitive surface structures. Improved safety profiles, flexibility in vaccine construction, and the ease of VLP production and purification have highlighted VLPs as attractive candidates for universal vaccine platform generation, although exploration of different types of expression systems for their development is needed. Here, we demonstrate the construction of several simple Escherichia coli expression systems for the generation of eggplant mosaic virus (EMV) VLP-derived vaccines. We used different principles of antigen incorporation, including direct fusion of EMV coat protein (CP) with major cat allergen Feld1, coexpression of antigen containing and unmodified (mosaic) EMV CPs, and two coexpression variants of EMV VLPs and antigen using synthetic zipper pair 18/17 (SYNZIP 18/17), and coiled-coil forming peptides E and K (Ecoil/Kcoil). Recombinant Fel d 1 chemically coupled to EMV VLPs was included as control experiments. All EMV-Feld1 variants were expressed in E. coli, formed Tymovirus-like VLPs, and were used for immunological evaluation in healthy mice. The immunogenicity of these newly developed vaccine candidates demonstrated high titers of Feld1-specific Ab production; however, a comparably high immune response against carrier EMV was also observed. Antibody avidity tests revealed very specific Ab production (more than 50% specificity) for four out of the five vaccine candidates. Native Feld1 recognition and subclass-specific antibody tests suggested that the EMV-SZ18/17-Feld1 complex and chemically coupled EMV-Feld1 vaccines may possess characteristics for further development.

Recent advancements in single dose slow-release devices for prophylactic vaccines

Single dose slow-release vaccines herald a new era in vaccine administration. An ideal device for slow-release vaccine delivery would be minimally invasive and self-administered, making these approaches an attractive alternative for mass vaccination programs, particularly during the time of a pandemic. In this review article, we discuss the latest advances in this field, specifically for prophylactic vaccines able to prevent infectious diseases. Recent studies have found that slow-release vaccines elicit better immune responses and often do not require cold chain transportation and storage, thus drastically reducing the cost, streamlining distribution, and improving efficacy. This promise has attracted significant attention, especially when poor patient compliance of the standard multidose vaccine regimes is considered. Single dose slow-release vaccines are the next generation of vaccine tools that could overcome most of the shortcomings of present vaccination programs and be the next platform technology to combat future pandemics. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Implantable Materials and Surgical Technologies > Nanomaterials and Implants Biology-Inspired Nanomaterials > Protein and Virus-Based Structures.

Gene Therapy of Extracellular Vesicles in Cardiovascular and Metabolic Diseases

The ultimate and most complex form of treating human diseases is embodied by gene therapy. For an effective gene therapeutic product we need to hack the cellular plasma membrane entry-system, then escaping degradation in the cytosol and in most cases, we need an efficient hacking of the nuclear membrane-system, achieving the delivery of genetic construct into the central stage of the target cells: nucleoplasm or chromosomal DNA found in this highly controlled space. These steps need to be performed in a targeted, ordered, and efficient way. Possessing intrinsic ability of nucleic acid and protein delivery, extracellular vesicles can bypass biological barriers and may be able to deliver a next-generation platform for gene therapy. Fine-tuned genetic constructs included in (synthetic) extracellular vesicles may provide an upgraded approach to the current gene therapeutical technologies by significantly upgrading and improving biosafety, versatility, and delivery, thus evoking the desired therapeutic response. This chapter addresses the main types, vectors, challenges, and safety issues of gene therapy. Afterwards, a brief introduction and beneficial roles of extracellular vesicles are given. The concept of engineering vesicles for gene therapy is also discussed. A snapshot of most relevant clinical trials in the field of cardiovascular and metabolic diseases is shown. Finally, a wrap-up and outlook about gene therapy are presented.

PEGylation and folic-acid functionalization of cationic lipoplexes-Improved nucleic acid transfer into cancer cells

Efficient and reliable transfer of nucleic acids for therapy applications is a major challenge. Stabilization of lipo- and polyplexes has already been successfully achieved by PEGylation. This modification reduces the interaction with serum proteins and thus prevents the lipoplexes from being cleared by the reticuloendothelial system. Problematically, this stabilization of lipoplexes simultaneously leads to reduced transfer efficiencies compared to non-PEGylated complexes. However, this reduction in transfer efficiency can be used to advantage since additional modification of PEGylated lipoplexes with functional groups enables improved selective transfer into target cells. Cancer cells overexpress folate receptors because of a significantly increased need of folate due to high cell proliferation rates. Thus, additional folate functionalization of PEGylated lipoplexes improves uptake into cancer cells. We demonstrate herein that NHS coupling chemistries can be used to modify two commercially available transfection reagents (Fuse-It-DNA and Lipofectamine® 3000) with NHS-PEG-folate for increased uptake of nucleic acids into cancer cells. Lipoplex characterization and functional analysis in cultures of cancer- and healthy cells clearly demonstrate that functionalization of PEGylated lipoplexes offers a promising method to generate efficient, stable and selective nucleic acid transfer systems.

Potential roles of hyaluronic acid in in vivo CAR T cell reprogramming for cancer immunotherapy

Chimeric antigen receptor (CAR) T cell therapy has recently shown unprecedented clinical efficacy for cancer treatment, particularly of hematological malignancies. However, the complex manufacturing processes that involve ex vivo genetic modification of autologous T cells limits its therapeutic application. CAR T cells generated in vivo provide a valid alternative immunotherapy, "off-the-shelf", for cancer treatment. This approach requires carriers for the delivery of CAR-encoding constructs, which are plasmid DNA or messenger RNA, to T cells for CAR expression to help eradicate the tumor. As such, there are a growing number of studies reporting gene delivery systems for in vivo CAR T cell therapy based on viral vectors and polymeric nanoparticles. Hyaluronic acid (HA) is a natural biopolymer that can serve for gene delivery, because of its inherent properties of cell recognition and internalization, as well as its biodegradability, biocompatibility, and presence of functional groups for the chemical conjugation of targeting ligands. In this review, the potential of HA in the delivery of CAR constructs is discussed on the basis of previous experience of HA-based nanoparticles for gene therapy. Furthermore, current studies on CAR carriers for in vivo-generated CAR T cells are included, giving an idea of a rational design of HA-based systems for the more efficient delivery of CAR to circulating T cells.

Post COVID-19 vaccination side effects and associated factors among vaccinated health care providers in Oromia region, Ethiopia in 2021

BACKGROUND

Severe Acute Respiratory Syndrome (SARS COV-2) known as COVID-19 since its outbreak in 2019, more than 375 and 5.6 million were infected and dead, respectively. Its influence in all disciplines stimulated different industries to work day to night relentlessly to develop safe and effective vaccines to reduce the catastrophic effect of the disease. With the increasing number of people globally who have been vaccinated, the reports on possible adverse events have grown and gained great public attention. This study aims to determine post-COVID-19 vaccination adverse effects and associated factors among vaccinated Health care providers in the Oromia region, Ethiopia in 2021.

METHODS

A cross-sectional study was conducted among 912 health care workers working in government hospitals in the central Oromia region from November 20 to December 15/2021. Respondents absent from work due to different reasons were excluded during the interview. The outcome variable was COVID-19 side effects (response as Yes/No). A descriptive analysis displayed findings in the form of the frequencies and percentages, and logistic regression was employed to see the association of different variables with side effects experienced.

RESULT

Overall, 92.1% of the participants experienced side effects either in 1st or 2nd doses of post-COVID-19 vaccination; 84.0% and (71.5%) of participants experienced at least one side effect in the 1st and 2nd dose of the vaccines, respectively. COVID-19 infection preventive protocols like keeping distance, hand wash using soap, wearing mask and using sanitizer were decreased post vaccination. About 74.3% of the respondents were worried about the adverse effects of the COVID-19 vaccine they received. The majority (80.2%) of the respondent felt fear while receiving the vaccine and 22.5% of the respondents suspect the effectiveness of the vaccine they took. About 14.8% of the vaccinated Health workers were infected by COVID-19 post-vaccination. Engaging in moderate physical activity and feeling fear when vaccinated were the independent factors associated with reported side effects of post-COVID-19 vaccination using multiple logistic regression. Respondents who did not engage in physical activity were 7.54 fold more likely to develop post-COVID-19 vaccination side effects compared to those who involved at least moderate-intensity physical activity[AOR = 7.54, 95% CI;2.46,23.12]. The odds of experiencing side effects among the respondents who felt fear when vaccinated were 10.73 times compared not felt fear (AOR = 10.73, 95% CI; 2.47,46.64), and similarly, those who felt little fear were 4.28 times more likely to experience side effects(AOR = 4.28, 95% CI; 1.28, 14.39).

CONCLUSION

Significant numbers of the respondents experienced side effects post COVID-19 vaccination. It is recommended to provide pre-awareness about the side effects to reduce observed anxiety related to the vaccine. It is also important to plan monitoring and evaluation of the post-vaccine effect using standard longitudinal study designs to measure the effects directly.

Smart Nanostructured Materials for SARS-CoV-2 and Variants Prevention, Biosensing and Vaccination

The coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has raised great concerns about human health globally. At the current stage, prevention and vaccination are still the most efficient ways to slow down the pandemic and to treat SARS-CoV-2 in various aspects. In this review, we summarize current progress and research activities in developing smart nanostructured materials for COVID-19 prevention, sensing, and vaccination. A few established concepts to prevent the spreading of SARS-CoV-2 and the variants of concerns (VOCs) are firstly reviewed, which emphasizes the importance of smart nanostructures in cutting the virus spreading chains. In the second part, we focus our discussion on the development of stimuli-responsive nanostructures for high-performance biosensing and detection of SARS-CoV-2 and VOCs. The use of nanostructures in developing effective and reliable vaccines for SARS-CoV-2 and VOCs will be introduced in the following section. In the conclusion, we summarize the current research focus on smart nanostructured materials for SARS-CoV-2 treatment. Some existing challenges are also provided, which need continuous efforts in creating smart nanostructured materials for coronavirus biosensing, treatment, and vaccination.

Perspective on the Application of Erythrocyte Liposome-Based Drug Delivery for Infectious Diseases

Nanoparticles are explored as drug carriers with the promise for the treatment of diseases to increase the efficacy and also reduce side effects sometimes seen with conventional drugs. To accomplish this goal, drugs are encapsulated in or conjugated to the nanocarriers and selectively delivered to their targets. Potential applications include immunization, the delivery of anti-cancer drugs to tumours, antibiotics to infections, targeting resistant bacteria, and delivery of therapeutic agents to the brain. Despite this great promise and potential, drug delivery systems have yet to be established, mainly due to their limitations in physical instability and rapid clearance by the host's immune response. Recent interest has been taken in using red blood cells (RBC) as drug carriers due to their naturally long circulation time, flexible structure, and direct access to many target sites. This includes coating of nanoparticles with the membrane of red blood cells, and the fabrication and manipulation of liposomes made of the red blood cells' cytoplasmic membrane. The properties of these erythrocyte liposomes, such as charge and elastic properties, can be tuned through the incorporation of synthetic lipids to optimize physical properties and the loading efficiency and retention of different drugs. Specificity can be established through the anchorage of antigens and antibodies in the liposomal membrane to achieve targeted delivery. Although still at an early stage, this erythrocyte-based platform shows first promising results in vitro and in animal studies. However, their full potential in terms of increased efficacy and side effect minimization still needs to be explored in vivo.

SARS-CoV-2 vaccine may trigger thyroid autoimmunity: real-life experience and review of the literature

PURPOSE

SARS-CoV-2 infection can be associated with destructive thyroiditis and triggers thyroid autoimmunity. More recent evidence suggests that SARS-CoV-2 vaccines may also be associated with permanent or transient thyroid dysfunction in susceptible individuals.

METHODS

We observed three patients who developed/exacerbated autoimmune thyroid diseases (AITDs) shortly after receiving mRNA-based vaccines against SARS-CoV2. Clinical histories are reported, and relevant literature in the field is summarized.

RESULTS

Our case series gives a description of the full spectrum of autoimmune disorders that may occur after SARS-CoV-2 vaccines administration, ranging from a case of new-onset Graves' disease to autoimmune hypothyroidism in two patients with pre-existing AITDs. Our three patients had a personal and/or family history of autoimmune disorders, suggesting that genetic predisposition is an important risk factor for the development of AITDs following vaccination. Moreover, our real-life experience demonstrates that persistent hypothyroidism may occur in the long run and should be overlooked; subjects with a previous AITDs are at risk of developing it. Reviewing the pertinent literature up to date Graves' disease is the most common vaccine-related AITDs with up to 51 cases reported in the literature, occurring mainly in female patients with no personal history of AIDTs, while only a case of autoimmune hypothyroidism has been reported so far.

CONCLUSIONS

SARS-CoV-2 vaccines can trigger autoimmune reactions and the present case series contributes to make clinicians aware of full spectrum of AITDs that may occur following vaccination. Thyroid function monitoring is recommended, mainly in subjects with a personal/family history of AITDs.

Mechanisms and challenges of nanocarriers as non-viral vectors of therapeutic genes for enhanced pulmonary delivery

With the rapid development of biopharmaceuticals and the outbreak of COVID-19, the world has ushered in a frenzy to develop gene therapy. Therefore, therapeutic genes have received enormous attention. However, due to the extreme instability and low intracellular gene expression of naked genes, specific vectors are required. Viral vectors are widely used attributed to their high transfection efficiency. However, due to the safety concerns of viral vectors, nanotechnology-based non-viral vectors have attracted extensive investigation. Still, issues of low transfection efficiency and poor tissue targeting of non-viral vectors need to be addressed. Especially, pulmonary gene delivery has obvious advantages for the treatment of inherited lung diseases, lung cancer, and viral pneumonia, which can not only enhance lung targeting and but also reduce enzymatic degradation. For systemic diseases therapy, pulmonary gene delivery can enhance vaccine efficacy via inducing not only cellular, humoral immunity but also mucosal immunity. This review provides a comprehensive overview of nanocarriers as non-viral vectors of therapeutic genes for enhanced pulmonary delivery. First of all, the characteristics and therapeutic mechanism of DNA, mRNA, and siRNA are provided. Thereafter, the advantages and challenges of pulmonary gene delivery in exerting local and systemic effects are discussed. Then, the inhalation dosage forms for nanoparticle-based drug delivery systems are introduced. Moreover, a series of materials used as nanocarriers for pulmonary gene delivery are presented, and the endosomal escape mechanisms of nanocarriers based on different materials are explored. The application of various non-viral vectors for pulmonary gene delivery are summarized in detail, with the perspectives of nano-vectors for pulmonary gene delivery.

Compliance with wearing facemasks by university teaching staff during the second wave of COVID-19 pandemic: a cross sectional study

Objective

We aimed to explore compliance with and barriers to wearing facemasks at the workplace among university teaching staff in Egypt.

Methods

An online survey was shared with teaching staff members at 11 public and 12 private Egyptian universities and high institutes, and 218 responses were received. All participants were asked about beliefs related to wearing facemasks. For participants who taught in-person classes, compliance with and barriers to wearing facemasks at the workplace were assessed. Compliance level was classified into: Non-compliance, inadequate and adequate, based on the degree of adherence to having facemasks on and not taking them off at five main work settings. We compared demographic characteristics, beliefs, and barriers scores across compliance levels.

Results

Most participants (81.7%) believed that facemasks reduce infection risk to others and 74.3% believed facemasks can reduce risk to the wearer. Around 80% of the respondents who taught in-person classes wore facemasks, but only 37.8% met the criteria of adequate compliance. Difficulty breathing and impaired communication were cited as major barriers by 42.2% and 30.3% of in-person class tutors respectively. The risk of reporting COVID-19 like symptoms among non-compliant participants was double the risk among those with adequate compliance (45.9% vs 25.7% respectively). Adequate compliance was significantly associated with higher positive beliefs scores and lower barriers scores.

Conclusion

Adequate compliance with wearing facemasks at the workplace was low. Addressing negative beliefs may improve compliance. Difficulty breathing, and impaired communication were important barriers, therefore we recommend replacing in-person interactions with online classes whenever applicable.

Supplementary Information

The online version contains supplementary material available at 10.1007/s44155-022-00011-3.

Relapses after SARS-CoV-2 vaccination in patients with neuromyelitis optica spectrum disorder and multiple sclerosis

BACKGROUND

The COVID-19 pandemic outbreak raises the question of whether immunization is recommended for patients with CNS demyelinating diseases. On the one hand, existing studies suggested that SARS-CoV-2 vaccinations are not associated with increased risk of relapse activity. On the other hand, case reports with acute CNS demyelinating disease post vaccination were emerging and raising clinicians' attention.

METHODS

In this longitudinal observational study, we included 556 patients with neuromyelitis optica spectrum disorder (NMOSD) and 280 patients with relapsing-remitting multiple sclerosis (RRMS). Each vaccinated patient was matched to two unvaccinated patients according to age, gender, ARR and immunotherapy status, based on propensity score matching model (PSM). The primary outcome is the short- and medium-term risk of relapse, which were evaluated by Kaplan-Meier analysis between groups.

RESULTS

In our cohort, 649 patients (77.6%) have not yet been vaccinated, mainly due to their concerns about relapse. After PSM, 109 vaccinated patients with NMOSD, 218 PS-matched unvaccinated patients with NMOSD, 78 vaccinated patients with RRMS, and 156 PS-matched unvaccinated patients with RRMS were included in the survival analysis to explore the safety of vaccines, with a median of 9-month follow-up. Following the first vaccination dose, 10 patients with NMOSD (9.2%) and four with RRMS (5.1%) experienced an acute relapse. Meanwhile, in the PS-matched unvaccinated group, 15 patients with NMOSD (6.9%) and 12 patients with RRMS (7.7%) presented with an acute relapse. There was no significant difference between the two curves in both NMOSD and RRMS groups over the course of the observation period. There were no significant differences in demographic characteristics, clinical characteristics, and symptoms of relapses between the vaccinated and PS-matched unvaccinated groups. Post vaccination adverse events (ADE) were reported in 39 individuals (20.9%).

CONCLUSION

Our results indicate that inactivated SARS-CoV-2 vaccines appear safe for patients with CNS demyelinating diseases.

Nanomaterials to combat SARS-CoV-2: Strategies to prevent, diagnose and treat COVID-19

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the associated coronavirus disease 2019 (COVID-19), which severely affect the respiratory system and several organs and tissues, and may lead to death, have shown how science can respond when challenged by a global emergency, offering as a response a myriad of rapid technological developments. Development of vaccines at lightning speed is one of them. SARS-CoV-2 outbreaks have stressed healthcare systems, questioning patients care by using standard non-adapted therapies and diagnostic tools. In this scenario, nanotechnology has offered new tools, techniques and opportunities for prevention, for rapid, accurate and sensitive diagnosis and treatment of COVID-19. In this review, we focus on the nanotechnological applications and nano-based materials (i.e., personal protective equipment) to combat SARS-CoV-2 transmission, infection, organ damage and for the development of new tools for virosurveillance, diagnose and immune protection by mRNA and other nano-based vaccines. All the nano-based developed tools have allowed a historical, unprecedented, real time epidemiological surveillance and diagnosis of SARS-CoV-2 infection, at community and international levels. The nano-based technology has help to predict and detect how this Sarbecovirus is mutating and the severity of the associated COVID-19 disease, thereby assisting the administration and public health services to make decisions and measures for preparedness against the emerging variants of SARS-CoV-2 and severe or lethal COVID-19.

In-House Innovative "Diamond Shaped" 3D Printed Microfluidic Devices for Lysozyme-Loaded Liposomes

Nanotechnology applications have emerged as one of the most actively researched areas in recent years. As a result, substantial study into nanoparticulate lipidic systems and liposomes (LPs) has been conducted. Regardless of the advantages, various challenges involving traditional manufacturing processes have hampered their expansion. Here, the combination of microfluidic technology (MF) and 3D printing (3DP) digital light processing (DLP) was fruitfully investigated in the creation of novel, previously unexplored "diamond shaped" devices suitable for the production of LPs carrying lysozyme as model drug. Computer-aided design (CAD) software was used designing several MF devices with significantly multiple and diverse geometries. These were printed using a high-performance DLP 3DP, resulting in extremely high-resolution chips that were tested to optimize the experimental condition of MF-based LPs. Monodisperse narrow-sized lysozyme-loaded PEGylated LPs were produced using in-house devices. The developed formulations succumbed to stability tests to determine their consistency, and then an encapsulation efficacy (EE) study was performed, yielding good findings. The in vitro release study indicated that lysozyme-loaded LPs could release up to 93% of the encapsulated cargo within 72 h. Therefore, the proficiency of the association between MF and 3DP was demonstrated, revealing a potential growing synergy.

A β-Cyclodextrin-Based Nanoparticle with Very High Transfection Efficiency Unveils siRNA-Activated TLR3 Responses in Human Prostate Cancer Cells

Synthetic double-stranded small interfering RNAs (siRNAs) mimic interference RNAs (RNAi) and can bind target mRNAs with a high degree of specificity, leading to selective knockdown of the proteins they encode. However, siRNAs are very labile and must be both protected and transported by nanoparticles to be efficiently delivered into cells. In this work, we used a Janus-type polycationic amphiphilic β-cyclodextrin derivative to efficiently transfect siRNAs targeting mRNAs encoding mitogen-activated protein kinase (p42-MAPK) or Ras homolog enriched in brain (Rheb) into different cancer cell lines as well as astrocytes. We took advantage of this high transfection efficiency to simultaneously knock down p42-MAPK and Rheb to boost docetaxel (DTX)-mediated toxicity in two human prostate cancer cell lines (LNCaP and PC3). We found that double knockdown of p42-MAPK and Rheb increased DTX-toxicity in LNCaP but not in PC3 cells. However, we also observed the same effect when scramble siRNA was used, therefore pointing to an off-target effect. Indeed, we found that the siRNA we used in this work induced toll-like receptor 3 activation, leading to β-interferon production and caspase activation. We believe that this mechanism could be very useful as a general strategy to elicit an immune response against prostate cancer cells.

Circular RNAs as emerging regulators in COVID-19 pathogenesis and progression

Coronavirus disease 2019 (COVID-19), an infectious acute respiratory disease caused by a newly emerging RNA virus, is a still-growing pandemic that has caused more than 6 million deaths globally and has seriously threatened the lives and health of people across the world. Currently, several drugs have been used in the clinical treatment of COVID-19, such as small molecules, neutralizing antibodies, and monoclonal antibodies. In addition, several vaccines have been used to prevent the spread of the pandemic, such as adenovirus vector vaccines, inactivated vaccines, recombinant subunit vaccines, and nucleic acid vaccines. However, the efficacy of vaccines and the onset of adverse reactions vary among individuals. Accumulating evidence has demonstrated that circular RNAs (circRNAs) are crucial regulators of viral infections and antiviral immune responses and are heavily involved in COVID-19 pathologies. During novel coronavirus infection, circRNAs not only directly affect the transcription process and interfere with viral replication but also indirectly regulate biological processes, including virus-host receptor binding and the immune response. Consequently, understanding the expression and function of circRNAs during severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection will provide novel insights into the development of circRNA-based methods. In this review, we summarize recent progress on the roles and underlying mechanisms of circRNAs that regulate the inflammatory response, viral replication, immune evasion, and cytokines induced by SARS-CoV-2 infection, and thus highlighting the diagnostic and therapeutic challenges in the treatment of COVID-19 and future research directions.

Clinical cardiovascular emergencies and the cellular basis of COVID-19 vaccination: from dream to reality?

OBJECTIVES

SARS-CoV-2 is responsible for the global COVID-19 pandemic, with little prevention or treatment options. More than 600 million mortalities have been documented from SARS-CoV-2 infection, with the majority of fatalities occurring among elderly patients (aged >65 years). A number of vaccines have been developed in an effort to restrain the rapid spread of SARS-CoV-2. Considering the widespread administration of these vaccines, substantial side or undesired effects in multiple organ systems have emerged, necessitating essential critical care. Herein, we tabulate the adverse cardiovascular responses resulting from COVID-19 vaccines.

DESIGN OR METHODS

We searched PubMed for articles published through April, 2022, with the terms "SARS-CoV-2", "COVID-19", "cardiovascular", "SARS-CoV-2 vaccines", "COVID-19 vaccines", "myocarditis", "pericarditis", "thrombosis", "thrombocytopenia", "vaccine-induced thrombotic thrombocytopenia", "acute coronary syndrome", "myocardial infarction", "hypertension", "arrythmia", "postural orthostatic tachycardia syndrome", "Takotsubo cardiomyopathy", "cardiac arrest" and "death". We mainly selected publications from the past 3 years, but did not exclude widely referenced and highly regarded older publications. Besides, we searched the reference lists of articles identified by above search method and chose those we considered relevant.

RESULTS

COVID-19 vaccines evoke rare but fatal thrombotic events, whereas messenger RNA\055based vaccines appear to be associated with risks of pericarditis/myocarditis, with the latter being more predominant in young adults following the second dose. Reports of other cardiovascular responses, including hypertension, arrhythmia, acute coronary syndrome, and cardiac arrest, have also been indicated.

CONCLUSION

The undesired cardiovascular complications remain infrequent, giveng the large number of vaccinations inoculated to general population. And lower mortality takes precedence over the undesired cardiovascular complications.

iVaccine-Deep: Prediction of COVID-19 mRNA vaccine degradation using deep learning

Messenger RNA (mRNA) has emerged as a critical global technology that requires global joint efforts from different entities to develop a COVID-19 vaccine. However, the chemical properties of RNA pose a challenge in utilizing mRNA as a vaccine candidate. For instance, the molecules are prone to degradation, which has a negative impact on the distribution of mRNA among patients. In addition, little is known of the degradation properties of individual RNA bases in a molecule. Therefore, this study aims to investigate whether a hybrid deep learning can predict RNA degradation from RNA sequences. Two deep hybrid neural network models were proposed, namely GCN_GRU and GCN_CNN. The first model is based on graph convolutional neural networks (GCNs) and gated recurrent unit (GRU). The second model is based on GCN and convolutional neural networks (CNNs). Both models were computed over the structural graph of the mRNA molecule. The experimental results showed that GCN_GRU hybrid model outperform GCN_CNN model by a large margin during the test time. Validation of proposed hybrid models is performed by well-known evaluation measures. Among different deep neural networks, GCN_GRU based model achieved best scores on both public and private MCRMSE test scores with 0.22614 and 0.34152, respectively. Finally, GCN_GRU pre-trained model has achieved the highest AuC score of 0.938. Such proven outperformance of GCNs indicates that modeling RNA molecules using graphs is critical in understanding molecule degradation mechanisms, which helps in minimizing the aforementioned issues. To show the importance of the proposed GCN_GRU hybrid model, in silico experiments has been contacted. The in-silico results showed that our model pays local attention when predicting a given position's reactivity and exhibits interesting behavior on neighboring bases in the sequence.

Type 1 diabetes mellitus following SARS-CoV-2 mRNA vaccination

PURPOSE

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) vaccines have been reported to trigger immune side effects. Type 1 diabetes as a manifestation of autoimmune/inflammatory syndrome induced by adjuvants has been reported in a limited number of cases after vaccinations. A few type 1 diabetes cases after SARS-CoV-2 vaccination have been reported. This study aims to report type 1 diabetes cases associated with the mRNA-based SARS-CoV-2 vaccination.

METHODS

We report four cases of type 1 diabetes mellitus after mRNA-based SARS-CoV-2 vaccine, BNT162b2 (Pfizer-BioNTech). In the medical history, one subject had autoimmune thyroid disease. All patients had autoantibodies against glutamate decarboxylase.

RESULTS

In the presented case series, type 1 diabetes developed a few weeks after BNT162b2 vaccination. After developing type 1 diabetes, the insulin dose requirements of all patients decreased rapidly, and the need for insulin therapy in three patients disappeared during follow-up. Acute deterioration of glucose regulation in a patient followed by BNT162b2 administration may be due to vaccine-induced autoimmune diabetes.

CONCLUSION

Vaccination with BNT162b2 may trigger type 1 diabetes.