Prospects for the use of spherical gold nanoparticles in immunization

A review on gold nanoparticles as an innovative therapeutic cue in bone tissue engineering: Prospects and future clinical applications

Bone damage is a complex orthopedic problem primarily caused by trauma, cancer, or bacterial infection of bone tissue. Clinical care management for bone damage remains a significant clinical challenge and there is a growing need for more advanced bone therapy options. Nanotechnology has been widely explored in the field of orthopedic therapy for the treatment of a severe bone disease. Among nanomaterials, gold nanoparticles (GNPs) along with other biomaterials are emerging as a new paradigm for treatment with excellent potential for bone tissue engineering and regenerative medicine applications. In recent years, a great deal of research has focused on demonstrating the potential for GNPs to provide for enhancement of osteogenesis, reduction of osteoclastogenesis/osteomyelitis, and treatment of bone cancer. This review details the latest understandings in regards to GNPs based therapeutic systems, mechanisms, and the applications of GNPs against various bone disorders. The present review aims to summarize i) the mechanisms of GNPs in bone tissue remodeling, ii) preparation methods of GNPs, and iii) functionalization of GNPs and its decoration on biomaterials as a delivery vehicle in a specific bone tissue engineering for future clinical application.

Current Trends and Prospects for Application of Green Synthesized Metal Nanoparticles in Cancer and COVID-19 Therapies

Cancer and COVID-19 have been deemed as world health concerns due to the millions of lives that they have claimed over the years. Extensive efforts have been made to develop sophisticated, site-specific, and safe strategies that can effectively diagnose, prevent, manage, and treat these diseases. These strategies involve the implementation of metal nanoparticles and metal oxides such as gold, silver, iron oxide, titanium oxide, zinc oxide, and copper oxide, formulated through nanotechnology as alternative anticancer or antiviral therapeutics or drug delivery systems. This review provides a perspective on metal nanoparticles and their potential application in cancer and COVID-19 treatments. The data of published studies were critically analysed to expose the potential therapeutic relevance of green synthesized metal nanoparticles in cancer and COVID-19. Although various research reports highlight the great potential of metal and metal oxide nanoparticles as alternative nanotherapeutics, issues of nanotoxicity, complex methods of preparation, biodegradability, and clearance are lingering challenges for the successful clinical application of the NPs. Thus, future innovations include fabricating metal nanoparticles with eco-friendly materials, tailor making them with optimal therapeutics for specific disease targeting, and in vitro and in vivo evaluation of safety, therapeutic efficiency, pharmacokinetics, and biodistribution.

Emerging peptide-based nanovaccines: From design synthesis to defense against cancer and infection

Peptide-based vaccines, which form one of the most potent vaccine platforms, offer exclusive advantages over classical vaccines that use whole organisms or proteins. However, peptides alone are still poor stability and weak immunogenicity, thus need a delivery system that can overcome these shortcomings. Currently, nanotechnology has been extensively utilized to address this issue. Nanovaccines, as new formulations of vaccines using nanoparticles (NPs) as carriers or adjuvants, are undergoing development instead of conventional vaccines. Indeed, peptide-based nanovaccine is a rapidly developing field of research that is emerging out of the confluence of antigenic peptides with the nano-delivery system. In this review, we shed light on the rational design and preparation strategies based on various nanomaterials of peptide-based nanovaccines, and we spotlight progress in the development of peptide-based nanovaccines against cancer and infectious diseases. Finally, the future prospects for development of peptide-based nanovaccines are presented.

Antiviral potential of nanoparticles for the treatment of Coronavirus infections

BACKGROUND

On 31st December 2019 in Wuhan, China, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), was acknowledged. This virus spread quickly throughout the world causing a global pandemic. The World Health Organization declared COVID-19 a pandemic disease on 11th March 2020. Since then, the whole world has come together and have developed several vaccines against this deadly virus. Similarly, several alternative searches for pandemic disease therapeutics are still ongoing. One of them has been identified as nanotechnology. It has demonstrated significant promise for detecting and inhibiting a variety of viruses, including coronaviruses. Several nanoparticles, including gold nanoparticles, silver nanoparticles, quantum dots, carbon dots, graphene oxide nanoparticles, and zinc oxide nanoparticles, have previously demonstrated remarkable antiviral activity against a diverse array of viruses.

OBJECTIVE

This review aims to provide a basic and comprehensive overview of COVID-19's initial global outbreak and its mechanism of infiltration into human host cells, as well as the detailed mechanism and inhibitory effects of various nanoparticles against this virus. In addition to nanoparticles, this review focuses on the role of several antiviral drugs used against COVID-19 to date.

CONCLUSION

COVID-19 has severely disrupted the social and economic lives of people all over the world. Due to a lack of adequate medical facilities, countries have struggled to maintain control of the situation. Neither a drug nor a vaccine has a 100% efficacy rate. As a result, nanotechnology may be a better therapeutic alternative for this pandemic disease.

Sensor System Based on a Piezoelectric Resonator with a Lateral Electric Field for Virus Diagnostics

A sensor system based on a piezoelectric resonator with a lateral electric field in the frequency range 6-7 MHz of the electric field for virus detection is described. Through use of the transmissible virus causing gastroenteritis in pigs and specific antibodies, the possibility of detecting the virus in suspension in real time was determined. It was found that the frequency dependence of the real and imaginary parts of the electrical impedance of such a resonator loaded with a virus suspension changes significantly after the addition of specific antibodies to the suspension. No changes are observed if the antibodies are not specific. Thus, the results obtained illustrate the possibility of detecting viruses in situ, directly in the liquid phase, if the change in the real or imaginary parts of the electrical impedance after the addition of antibodies is used as an analytical signal. The possibility of virus detection in the presence of foreign viral particles has been illustrated.

Efficacy and Immune Response Elicited by Gold Nanoparticle- Based Nanovaccines against Infectious Diseases

The use of nanoparticles for developing vaccines has become a routine process for researchers and pharmaceutical companies. Gold nanoparticles (GNPs) are chemical inert, have low toxicity, and are easy to modify and functionalize, making them an attractive choice for nanovaccine development. GNPs are modified for diagnostics and detection of many pathogens. The biocompatibility and biodistribution properties of GNPs render them ideal for use in clinical settings. They have excellent immune modulatory and adjuvant properties. They have been used as the antigen carrier for the delivery system to a targeted site. Tagging them with antibodies can direct the drug or antigen-carrying GNPs to specific tissues or cells. The physicochemical properties of the GNP, together with its dynamic immune response based on its size, shape, surface charge, and optical properties, make it a suitable candidate for vaccine development. The clear outcome of modulating dendritic cells, T and B lymphocytes, which trigger cytokine release in the host, indicates GNPs' efficiency in combating pathogens. The high titer of IgG and IgA antibody subtypes and their enhanced capacity to neutralize pathogens are reported in multiple studies on GNP-based vaccine development. The major focus of this review is to illustrate the role of GNPs in developing nanovaccines against multiple infectious agents, ranging from viruses to bacteria and parasites. Although the use of GNPs has its shortcomings and a low but detectable level of toxicity, their benefits warrant investing more thought and energy into the development of novel vaccine strategies.

Metallic Nanoparticles: A New Frontier in the Fight Against Leishmaniasis

Abstract:

Leishmaniasis is a cutaneous, mucocutaneous, or visceral parasitic disease caused by protozoa of the Leishmania genus. According to the World Health Organization, Leishmaniasis causes approximately 20–40 thousand deaths annually, and Brazil, India, and some countries in Africa are the most affected by this neglected disease. In addition to parasite’s ability to evade the host’s immune system, the incidence of vectors, the genetics of different hosts, and the large number of deaths are mainly due to failures in conventional treatments that have high toxicity, low effectiveness, and prolonged therapeutic regimens. Thus, the development of new alternative therapeutics with more effective and safer actions has become one of the main challenges for researchers studying leishmaniasis. Among the many research and tested options, metallic nanoparticles, such as gold, silver, zinc oxide, and titanium dioxide, have been shown to be one of the most promising therapeutic tool because they are easily prepared and chemically modified, have a broad spectrum of action, low toxicity, and can generate reactive oxygen species and other immune responses that favor their use against different species of Leishmania. This review explores the progress of the use of metallic nanoparticles as a new tool in the treatment of leishmaniasis, as well as discusses the gaps in knowledge that need to be addressed to consolidate a safe, effective, and definitive therapeutic intervention against these infections.

Current Prospects in Peptide-Based Subunit Nanovaccines

Vaccination renders protection against pathogens via stimulation of the body's natural immune responses. Classical vaccines that utilize whole organisms or proteins have several disadvantages, such as induction of undesired immune responses, poor stability, and manufacturing difficulties. The use of minimal immunogenic pathogen components as vaccine antigens, i.e., peptides, can greatly reduce these shortcomings. However, subunit antigens require a specific delivery system and immune adjuvant to increase their efficacy. Recently, nanotechnology has been extensively utilized to address this issue. Nanotechnology-based formulation of peptide vaccines can boost immunogenicity and efficiently induce cellular and humoral immune responses. This chapter outlines the recent developments and advances of nano-sized delivery platforms for peptide antigens, including nanoparticles composed of polymers, peptides, lipids, and inorganic materials.

Optimization of Multivalent Gold Nanoparticle Vaccines Eliciting Humoral and Cellular Immunity in an In Vivo Model of Enterohemorrhagic Escherichia coli O157:H7 Colonization

Enterohemorrhagic Escherichia coli (EHEC) O157:H7 remains a pathogen of significance and high consequence around the world. This outcome is due in part to the high economic impact associated with massive, contaminated product recalls, prevalence of the pathogen in carrier reservoirs, disease sequelae, and mortality associated with several outbreaks worldwide. Furthermore, the contraindication of antibiotic use for the treatment of EHEC-related infections makes this pathogen a primary candidate for the development of effective prophylactic vaccines. However, no vaccines are approved for human use, and many have failed to provide a high degree of efficacy or broad protection, thereby opening an avenue for the use of new technologies to produce a safe, effective, and protective vaccine. Building on our previous studies using reverse vaccinology-predicted antigens, we refine a formulation, evaluate new immunogenic antigens, and further expand our understanding about the mechanism of EHEC vaccine-mediated protection. In the current study, we exploit the use of the nanotechnology platform based on gold nanoparticles (AuNP), which can act as a scaffold for the delivery of various antigens. Our results demonstrate that a refined vaccine formulation incorporating EHEC antigen LomW, EscC, LpfA1, or LpfA2 and delivered using AuNPs can elicit robust antigen-specific cellular and humoral responses associated with reduced EHEC colonization in vivo. Furthermore, our in vitro mechanistic studies further support that antibody-mediated protection is primarily driven by inhibition of bacterial adherence onto intestinal epithelial cells and by promotion of macrophage uptake and killing.

IMPORTANCE Enterohemorrhagic E. coli O157:H7 remains an important human pathogen that does not have an effective and safe vaccine available. We have made outstanding progress in the identification of novel protective antigens that have been incorporated into the gold nanoparticle platform and used as vaccines. In this study, we have refined our vaccine formulations to incorporate multiple antigens and further define the mechanism of antibody-mediated protection, including one vaccine that promotes macrophage uptake. We further define the cell-mediated responses elicited at the mucosal surface by our nanovaccine formulations, another key immune mechanism linked to protection.

Synthesis, Characterization, Immune Regulation, and Antioxidative Assessment of Yeast-Derived Selenium Nanoparticles in Cyclophosphamide-Induced Rats

This article introduces an environmentally friendly and more economical method for preparing red selenium nanoparticles (Se-NPs) with high stability, good biocompatibility, and narrow size using yeast as a bio-reducing agent with high antioxidant, immune regulation, and low toxicity than inorganic and organic Se. The yeast-derived Se-NPs were characterized by scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The results revealed spherical-shaped particles of Se-NPs with an average diameter of 71.14 ± 18.17 nm, an amorphous structure, and surface enhancement with an organic shell layer, that provide precise geometry and stability in the formation of bio-inert gray or black Se-NPs instead of red Se-NPs. Furthermore, the addition of 0.3-0.8 mg/kg Se-NPs in the feed significantly improved the health of mice. As Se-NPs stimulated the oxidative state of mice, it significantly increased the level of GSH-Px, SOD, and AOC, and decreased the level of MDA. The yeast-derived Se-NPs alleviated the immunosuppression induced by cyclophosphamide, whereas protected the liver, spleen, and kidney of mice, stimulated the humoral immune potential of the mice, and significantly increased the levels of I g M, IgA, and I g G. These results indicated that the yeast-derived Se-NPs, as a trace element feed additive, increased the defense of the animal against oxidative stress and infectious diseases and therefore Se-NPs can be used as a potential antibiotic substitute for animal husbandry.

Nanotherapeutics for treating coronavirus diseases

Viral diseases have recently become a threat to human health and rapidly become a significant cause of mortality with a continually exacerbated unfavorable socio-economic impact. Coronaviruses, including severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome (MERS-CoV), and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), have threatened human life, with immense accompanying morbidity rates; the COVID-19 (caused by SARS-CoV-2) epidemic has become a severe threat to global public health. In addition, the design process of antiviral medications usually takes years before the treatments can be made readily available. Hence, it is necessary to invest scientifically and financially in a technology platform that can then be quickly repurposed on demand to be adequately positioned for this kind of pandemic situation through lessons learned from the previous pandemics. Nanomaterials/nanoformulations provide such platform technologies, and a proper investigation into their basic science and biological interactions would be of great benefit for potential vaccine and therapeutic development. In this respect, intelligent and advanced nano-based technologies provide specific physico-chemical properties, which can help fix the key issues related to the treatments of viral infections. This review aims to provide an overview of the latest research on the effective use of nanomaterials in the treatment of coronaviruses. Also raised are the problems, perspectives of antiviral nanoformulations, and the possibility of using nanomaterials effectively against current pandemic situations.

Emerging Therapeutic Approaches to Combat COVID-19: Present Status and Future Perspectives

Coronavirus disease (COVID-19) has emerged as a fast-paced epidemic in late 2019 which is disrupting life-saving immunization services. SARS-CoV-2 is a highly transmissible virus and an infectious disease that has caused fear among people across the world. The worldwide emergence and rapid expansion of SARS-CoV-2 emphasizes the need for exploring innovative therapeutic approaches to combat SARS-CoV-2. The efficacy of some antiviral drugs such as remdesivir, favipiravir, umifenovir, etc., are still tested against SARS-CoV-2. Additionally, there is a large global effort to develop vaccines for the protection against COVID-19. Because vaccines seem the best solution to control the pandemic but time is required for its development, pre-clinical/clinical trials, approval from FDA and scale-up. The nano-based approach is another promising approach to combat COVID-19 owing to unique physicochemical properties of nanomaterials. Peptide based vaccines emerged as promising vaccine candidates for SARS-CoV-2. The study emphasizes the current therapeutic approaches against SARS-CoV-2 and some of the potential candidates for SARS-CoV-2 treatment which are still under clinical studies for their effectiveness against SARS-CoV-2. Overall, it is of high importance to mention that clinical trials are necessary for confirming promising drug candidates and effective vaccines and the safety profile of the new components must be evaluated before translation of in vitro studies for implementation in clinical use.

Acoustical Slot Mode Sensor for the Rapid Coronaviruses Detection

A method for the rapid detection of coronaviruses is presented on the example of the transmissible gastroenteritis virus (TGEV) directly in aqueous solutions with different conductivity. An acoustic sensor based on a slot wave in an acoustic delay line was used for the research. The addition of anti-TGEV antibodies (Abs) diluted in an aqueous solution led to a change in the depth and frequency of resonant peaks on the frequency dependence of the insertion loss of the sensor. The difference in the output parameters of the sensor before and after the biological interaction of the TGE virus in solutions with the specific antibodies allows drawing a conclusion about the presence/absence of the studied viruses in the analyzed solution. The possibility for virus detection in aqueous solutions with the conductivity of 1.9–900 μs/cm, as well as in the presence of the foreign viral particles, has been demonstrated. The analysis time did not exceed 10 min.

Ayurvedic metal nanoparticles could be novel antiviral agents against SARS-CoV-2

PURPOSE OF REVIEW

The pandemic COVID-19 has affected more than seventy million people globally. The whole world is eagerly waiting for an effective antiviral therapy to combat COVID-19, but it is yet to get. The emergence of COVID-19 makes imperative the need for safe and potent antiviral drugs. Many metal nanoparticles exhibit significant antiviral potential against many viral diseases. The Ayurvedic system of medicine is the treasure of many metal nanoparticulate drugs termed as Bhasma.

RECENT FINDINGS

Gold, silver, copper, zinc and iron oxide nanoparticles are effective against coronavirus. A possible mechanism of action of the metal nanoparticles against coronavirus is a disruption of outer layers of coronavirus. Swarna Bhasma, Rajata Bhasma, Tamra Bhasma and Yashada Bhasma are recommended for COVID-19 treatment due to the ability to reduce the plasma interleukins, interferons and TNFα levels.

SUMMARY

The Ayurvedic Bhasma preparations are unique metal nanoparticles. These metal nanoparticles are safe, stable in solid state and are having excellent biological activities. Ayurvedic metal nanoparticles, Swarna Bhasma, Rajata Bhasma, Tamra Bhasma and Yashada Bhasma could be proved as novel antiviral agents against SARS-CoV-2 for their anti-inflammatory, immunomodulatory, antiviral and adjuvant activities.

Silver-Based Nanomaterials as Therapeutic Agents Against Coronaviruses: A Review

Since the identification of the first human coronavirus in the 1960s, a total of six coronaviruses that are known to affect humans have been identified: 229E, OC43, severe acute respiratory syndrome coronavirus (SARS-CoV), NL63, HKU1, and Middle East respiratory syndrome coronavirus (MERS-CoV). Presently, the human world is affected by a novel version of the coronavirus family known as SARS-CoV-2, which has an extremely high contagion rate. Although the infection fatality rate (IFR) of this rapidly spreading virus is not high (ranging from 0.00% to 1.54% across 51 different locations), the increasing number of infections and deaths has created a worldwide pandemic situation. To provide therapy to severely infected patients, instant therapeutic support is urgently needed and the repurposing of already approved drugs is presently in progress. In this regard, the development of nanoparticles as effective transporters for therapeutic drugs or as alternative medicines is highly encouraged and currently needed. The size range of the viruses is within 60-140 nm, which is slightly larger than the diameters of nanoparticles, making nanomaterials efficacious tools with antiviral properties. Silver-based nanomaterials (AgNMs) demonstrate antimicrobial and disinfectant effects mostly by generating reactive oxygen species (ROS) and are presently considered as a versatile tool for the treatment of COVID-19 patients. Other metal-based nanoparticles have been primarily reported as delivery agents or surface modifying agents, vaccine adjuvant against coronavirus. The present review summarizes and discusses the possible effectiveness of various surface-modified AgNMs against animal coronaviruses and presents a concept for AgNM-based therapeutic treatment of SARS-CoV-2 in the near future.

Hard Nanomaterials in Time of Viral Pandemics

The SARS-Cov-2 pandemic has spread worldwide during 2020, setting up an uncertain start of this decade. The measures to contain infection taken by many governments have been extremely severe by imposing home lockdown and industrial production shutdown, making this the biggest crisis since the second world war. Additionally, the continuous colonization of wild natural lands may touch unknown virus reservoirs, causing the spread of epidemics. Apart from SARS-Cov-2, the recent history has seen the spread of several viral pandemics such as H2N2 and H3N3 flu, HIV, and SARS, while MERS and Ebola viruses are considered still in a prepandemic phase. Hard nanomaterials (HNMs) have been recently used as antimicrobial agents, potentially being next-generation drugs to fight viral infections. HNMs can block infection at early (disinfection, entrance inhibition) and middle (inside the host cells) stages and are also able to mitigate the immune response. This review is focused on the application of HNMs as antiviral agents. In particular, mechanisms of actions, biological outputs, and limitations for each HNM will be systematically presented and analyzed from a material chemistry point-of-view. The antiviral activity will be discussed in the context of the different pandemic viruses. We acknowledge that HNM antiviral research is still at its early stage, however, we believe that this field will rapidly blossom in the next period.

The Potential of Various Nanotechnologies for Coronavirus Diagnosis/Treatment Highlighted through a Literature Analysis

With the current COVID-19 outbreak, it has become essential to develop efficient methods for the treatment and detection of this virus. Among the new approaches that could be tested, that relying on nanotechnology finds one of its main grounds in the similarity between nanoparticle (NP) and coronavirus (COV) sizes, which promotes NP-COV interactions. Since COVID-19 is very recent, most studies in this field have focused on other types of coronavirus than COVID-19, such as those involved in MERS or SARS diseases. Although their number is limited, they have led to promising results on various COV using a wide range of different types of nanosystems, e.g., nanoparticles, quantum dos, or nanoassemblies of polymers/proteins. Additional efforts deserve to be spent in this field to consolidate these findings. Here, I first summarize the different nanotechnology-based methods used for COV detection, i.e., optical, electrical, or PCR ones, whose sensitivity was improved by the presence of nanoparticles. Furthermore, I present vaccination methods, which comprise nanoparticles used either as adjuvants or as active principles. They often yield a better-controlled immune response, possibly due to an improved antigen presentation/processing than in non-nanoformulated vaccines. Certain antiviral approaches also took advantage of nanoparticle uses, leading to specific mechanisms such as the blocking of virus replication at the cellular level or the reduction of a COV induced apoptotic cellular death.

Why have nanotechnologies been underutilized in the global uprising against the coronavirus pandemic?

Prior research on nanotechnologies in diagnostics, prevention and treatment of coronavirus infections is reviewed. Gold nanoparticles and semiconductor quantum dots in colorimetric and immunochromatographic assays, silica nanoparticles in the polymerase chain reaction and spike protein nanospheres as antigen carriers and adjuvants in vaccine formulations present notable examples in diagnostics and prevention, while uses of nanoparticles in coronavirus infection treatments have been merely sporadic. The current absence of antiviral therapeutics that specifically target human coronaviruses, including SARS-CoV-2, might be largely due to the underuse of nanotechnologies. Elucidating the interface between nanoparticles and coronaviruses is timely, but presents the only route to the rational design of precisely targeted therapeutics for coronavirus infections. Such a fundamental approach is also a viable prophylaxis against future pandemics of this type.

Gold nanoparticles for preparation of antibodies and vaccines against infectious diseases

INTRODUCTION

Vaccination remains very effective in stimulating protective immune responses against infections. An important task in antibody and vaccine preparation is to choose an optimal carrier that will ensure a high immune response. Particularly promising in this regard are nanoscale particle carriers. An antigen that is adsorbed or encapsulated by nanoparticles can be used as an adjuvant to optimize the immune response during vaccination. a very popular antigen carrier used for immunization and vaccination is gold nanoparticles, with are being used to make new vaccines against viral, bacterial, and parasitic infections.

AREAS COVERED

This review summarizes what is currently known about the use of gold nanoparticles as an antigen carrier and adjuvant to prepare antibodies in vivo and design vaccines against viral, bacterial, and parasitic infections. The basic principles, recent advances, and current problems in the use of gold nanoparticles are discussed.

EXPERT OPINION

Gold nanoparticles can be used as adjuvants to increase the effectiveness of vaccines by stimulating antigen-presenting cells and ensuring controlled antigen release. Studying the characteristics of the immune response obtained from the use of gold nanoparticles as a carrier and an adjuvant will permit the particles' potential for vaccine design to be increased.

Advances in Lipid and Metal Nanoparticles for Antimicrobial Peptide Delivery

Antimicrobial peptides (AMPs) have been described as excellent candidates to overcome antibiotic resistance. Frequently, AMPs exhibit a wide therapeutic window, with low cytotoxicity and broad-spectrum antimicrobial activity against a variety of pathogens. In addition, some AMPs are also able to modulate the immune response, decreasing potential harmful effects such as sepsis. Despite these benefits, only a few formulations have successfully reached clinics. A common flaw in the druggability of AMPs is their poor pharmacokinetics, common to several peptide drugs, as they may be degraded by a myriad of proteases inside the organism. The combination of AMPs with carrier nanoparticles to improve delivery may enhance their half-life, decreasing the dosage and thus, reducing production costs and eventual toxicity. Here, we present the most recent advances in lipid and metal nanodevices for AMP delivery, with a special focus on metal nanoparticles and liposome formulations.