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Science Translational Medicine Jul 2022Influenza A viruses (IAVs) present major public health threats from annual seasonal epidemics and pandemics and from viruses adapted to a variety of animals including...
Influenza A viruses (IAVs) present major public health threats from annual seasonal epidemics and pandemics and from viruses adapted to a variety of animals including poultry, pigs, and horses. Vaccines that broadly protect against all such IAVs, so-called "universal" influenza vaccines, do not currently exist but are urgently needed. Here, we demonstrated that an inactivated, multivalent whole-virus vaccine, delivered intramuscularly or intranasally, was broadly protective against challenges with multiple IAV hemagglutinin and neuraminidase subtypes in both mice and ferrets. The vaccine is composed of four β-propiolactone-inactivated low-pathogenicity avian IAV subtypes of H1N9, H3N8, H5N1, and H7N3. Vaccinated mice and ferrets demonstrated substantial protection against a variety of IAVs, including the 1918 H1N1 strain, the highly pathogenic avian H5N8 strain, and H7N9. We also observed protection against challenge with antigenically variable and heterosubtypic avian, swine, and human viruses. Compared to control animals, vaccinated mice and ferrets demonstrated marked reductions in viral titers, lung pathology, and host inflammatory responses. This vaccine approach indicates the feasibility of eliciting broad, heterosubtypic IAV protection and identifies a promising candidate for influenza vaccine clinical development.
Topics: Animals; Antibodies, Viral; Ferrets; Horses; Humans; Influenza A Virus, H1N1 Subtype; Influenza A Virus, H3N8 Subtype; Influenza A Virus, H5N1 Subtype; Influenza A Virus, H7N3 Subtype; Influenza A Virus, H7N9 Subtype; Influenza Vaccines; Mice; Orthomyxoviridae Infections; Swine
PubMed: 35857640
DOI: 10.1126/scitranslmed.abo2167 -
Biochemistry. Biokhimiia Jul 2021COVID-19, a new human respiratory disease that has killed nearly 3 million people in a year since the start of the pandemic, is a global public health challenge. Its... (Review)
Review
COVID-19, a new human respiratory disease that has killed nearly 3 million people in a year since the start of the pandemic, is a global public health challenge. Its infectious agent, SARS-CoV-2, differs from other coronaviruses in a number of structural features that make this virus more pathogenic and transmissible. In this review, we discuss some important characteristics of the main SARS-CoV-2 surface antigen, the spike (S) protein, such as (i) ability of the receptor-binding domain (RBD) to switch between the "standing-up" position (open pre-fusion conformation) for receptor binding and the "lying-down" position (closed pre-fusion conformation) for immune system evasion; (ii) advantage of a high binding affinity of the RBD open conformation to the human angiotensin-converting enzyme 2 (ACE2) receptor for efficient cell entry; and (iii) S protein preliminary activation by the intracellular furin-like proteases for facilitation of the virus spreading across different cell types. We describe interactions between the S protein and cellular receptors, co-receptors, and antagonists, as well as a hypothetical mechanism of the homotrimeric spike structure destabilization that triggers the fusion of the viral envelope with the cell membrane at physiological pH and mediates the viral nucleocapsid entry into the cytoplasm. The transition of the S protein pre-fusion conformation to the post-fusion one on the surface of virions after their treatment with some reagents, such as β-propiolactone, is essential, especially in relation to the vaccine production. We also compare the COVID-19 pathogenesis with that of severe outbreaks of "avian" influenza caused by the A/H5 and A/H7 highly pathogenic viruses and discuss the structural similarities between the SARS-CoV-2 S protein and hemagglutinins of those highly pathogenic strains. Finally, we touch on the prospective and currently used COVID-19 antiviral and anti-pathogenetic therapeutics, as well as recently approved conventional and innovative COVID-19 vaccines and their molecular and immunological features.
Topics: Angiotensin-Converting Enzyme 2; COVID-19; Humans; Influenza A virus; Influenza, Human; Pandemics; SARS-CoV-2; Spike Glycoprotein, Coronavirus
PubMed: 34284707
DOI: 10.1134/S0006297921070026 -
International Journal of Molecular... Jun 2017Although the copolymerizations of l-lactide (LA) with seven- or six-membered ring lactones have been extensively studied, the copolymerizations of LA with four-membered...
Although the copolymerizations of l-lactide (LA) with seven- or six-membered ring lactones have been extensively studied, the copolymerizations of LA with four-membered ring lactones have scarcely been reported. In this work, we studied the copolymerization of LA with β-propiolactone (PL) and the properties of the obtained copolymers. The copolymerization of LA with PL was carried out using trifluoromethanesulfonic acid as a catalyst and methanol as an initiator to produce poly(LA--PL) with of ~50,000 and PL-content of 6-67 mol %. The values of the copolymers were rapidly lowered with increasing PL-contents. The and Δ of the copolymers gradually decreased with increasing PL-contents, indicating their decreased crystallinity. Biodegradation test of the copolymers in compost demonstrated their improved biodegradability in comparison with the homopolymer of LA.
Topics: Biocompatible Materials; Biodegradation, Environmental; Catalysis; Dioxanes; Lactones; Materials Testing; Molecular Weight; Polymerization; Polymers; Propiolactone; Temperature
PubMed: 28632154
DOI: 10.3390/ijms18061312 -
Chemical Research in Toxicology Mar 2020The discovery that β-propiolactone (BPL), once a commercially important chemical, causes various tumors in experimental animals has led to a significant decrease in its...
The discovery that β-propiolactone (BPL), once a commercially important chemical, causes various tumors in experimental animals has led to a significant decrease in its use. However, owing to its efficacy this possible human carcinogen remains to be utilized in vaccines for inactivation of viruses. The focus of the current study was to uncover the mechanisms of β-propiolactone reactions with both nucleobases and glutathione (GSH) through computer simulations based on quantum chemical methods. Our results, in accordance with in vitro studies, show that among all nucleobases guanine most readily forms adducts with BPL through S2 reaction mechanism. Acquired activation energies with incorporated solvent effects reveal that alkylation represents an energetically more favorable reaction than acylation for all nucleobases. Comparison of activation free energies of glutathione and guanine reactions with BPL suggest that glutathione may represent an efficient natural scavenger of BPL. Therefore, glutathione present in the organism may provide protection to the DNA and thus prevent BPL's genotoxicity, mutagenicity, and possibly even carcinogenicity.
Topics: Carcinogenesis; Density Functional Theory; Humans; Models, Molecular; Molecular Structure; Propiolactone; Thermodynamics
PubMed: 32056425
DOI: 10.1021/acs.chemrestox.9b00389 -
Viruses Jun 2020In late 2019, a novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan, the capital of the Chinese province Hubei. Since then,...
In late 2019, a novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan, the capital of the Chinese province Hubei. Since then, SARS-CoV-2 has been responsible for a worldwide pandemic resulting in over 4 million infections and over 250,000 deaths. The pandemic has instigated widespread research related to SARS-CoV-2 and the disease that it causes, COVID-19. Research into this new virus will be facilitated by the availability of clearly described and effective procedures that enable the propagation and quantification of infectious virus. As work with the virus is recommended to be performed at biosafety level 3, validated methods to effectively inactivate the virus to enable the safe study of RNA, DNA, and protein from infected cells are also needed. Here, we report methods used to grow SARS-CoV-2 in multiple cell lines and to measure virus infectivity by plaque assay using either agarose or microcrystalline cellulose as an overlay as well as a SARS-CoV-2 specific focus forming assay. We also demonstrate effective inactivation by TRIzol, 10% neutral buffered formalin, beta propiolactone, and heat.
Topics: Animals; Betacoronavirus; COVID-19; Cellulose; Chlorocebus aethiops; Coronavirus Infections; Culture Media; Formaldehyde; Guanidines; HEK293 Cells; Humans; Pandemics; Phenols; Pneumonia, Viral; Propiolactone; SARS-CoV-2; Sepharose; Vero Cells; Viral Plaque Assay; Virus Inactivation
PubMed: 32517266
DOI: 10.3390/v12060622 -
Pathogens (Basel, Switzerland) Feb 2022The handling of highly pathogenic viruses, whether for diagnostic or research purposes, often requires an inactivation step. This article reviews available inactivation... (Review)
Review
The handling of highly pathogenic viruses, whether for diagnostic or research purposes, often requires an inactivation step. This article reviews available inactivation techniques published in peer-reviewed journals and their benefits and limitations in relation to the intended application. The bulk of highly pathogenic viruses are represented by enveloped RNA viruses belonging to the , , , , , , , and families. Here, we summarize inactivation methods for these virus families that allow for subsequent molecular and serological analysis or vaccine development. The techniques identified here include: treatment with guanidium-based chaotropic salts, heat inactivation, photoactive compounds such as psoralens or 1.5-iodonaphtyl azide, detergents, fixing with aldehydes, UV-radiation, gamma irradiation, aromatic disulfides, beta-propiolacton and hydrogen peroxide. The combination of simple techniques such as heat or UV-radiation and detergents such as Tween-20, Triton X-100 or Sodium dodecyl sulfate are often sufficient for virus inactivation, but the efficiency may be affected by influencing factors including quantity of infectious particles, matrix constitution, pH, salt- and protein content. Residual infectivity of the inactivated virus could have disastrous consequences for both laboratory/healthcare personnel and patients. Therefore, the development of inactivation protocols requires careful considerations which we review here.
PubMed: 35215213
DOI: 10.3390/pathogens11020271 -
Viruses Aug 2022Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused huge social and economic distress. Given its rapid spread and the lack of specific treatment...
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused huge social and economic distress. Given its rapid spread and the lack of specific treatment options, SARS-CoV-2 needs to be inactivated according to strict biosafety measures during laboratory diagnostics and vaccine development. The inactivation method for SARS-CoV-2 affects research related to the natural virus and its immune activity as an antigen in vaccines. In this study, we used size exclusion chromatography, western blotting, ELISA, an electron microscope, dynamic light scattering, circular dichroism, and surface plasmon resonance to evaluate the effects of four different chemical inactivation methods on the physical and biochemical characterization of SARS-CoV-2. Formaldehyde and β-propiolactone (BPL) treatment can completely inactivate the virus and have no significant effects on the morphology of the virus. None of the four tested inactivation methods affected the secondary structure of the virus, including the α-helix, antiparallel β-sheet, parallel β-sheet, β-turn, and random coil. However, formaldehyde and long-term BPL treatment (48 h) resulted in decreased viral S protein content and increased viral particle aggregation, respectively. The BPL treatment for 24 h can completely inactivate SARS-CoV-2 with the maximum retention of the morphology, physical properties, and the biochemical properties of the potential antigens of the virus. In summary, we have established a characterization system for the comprehensive evaluation of virus inactivation technology, which has important guiding significance for the development of vaccines against SARS-CoV-2 variants and research on natural SARS-CoV-2.
Topics: Antibodies, Viral; COVID-19; COVID-19 Vaccines; Formaldehyde; Humans; Propiolactone; SARS-CoV-2; Vaccines, Inactivated
PubMed: 36146745
DOI: 10.3390/v14091938 -
International Journal of Molecular... Apr 2022Polyethylenimine (PEI) has been widely used in gene delivery. However, its high cytotoxicity and undesired non-specific protein adsorption hinder the overall delivery...
Polyethylenimine (PEI) has been widely used in gene delivery. However, its high cytotoxicity and undesired non-specific protein adsorption hinder the overall delivery efficacy and the practical applications of PEI-based gene delivery systems. In this study, we prepared hydrophobically modified PEIs (H-PEIs) via the reaction of octanal with 40% of primary amines in PEI and PEI, respectively. Two common zwitterionic molecules, 1,3-propanesultone and β-propiolactone, were then used for the modification of the resulting H-PEIs to construct polycationic gene carriers with zwitterionic properties (H-zPEIs). The siRNA delivery efficiency and cytotoxicity of these materials were evaluated in Hela-Luc and A549-Luc cell lines. Compared with their respective parental H-PEIs, different degrees of zwitterionic modification showed different effects in reducing cytotoxicity and delivery efficiency. All zwitterion-modified PEIs showed excellent siRNA binding capacity, reduced nonspecific protein adsorption, and enhanced stability upon nuclease degradation. It is concluded that zwitterionic molecular modification is an effective method to construct efficient vectors by preventing undesired interactions between polycationic carriers and biomacromolecules. It may offer insights into the modification of other cationic carriers of nucleic acid drugs.
Topics: Gene Transfer Techniques; Genetic Therapy; HeLa Cells; Humans; Polyethyleneimine; RNA, Small Interfering; Transfection
PubMed: 35563405
DOI: 10.3390/ijms23095014 -
Archives of Medical Research Jan 2021The Coronavirus disease 2019 (COVID-19) pandemic has spread to almost all nooks and corners of the world. There are numerous potential approaches to pharmacologically... (Review)
Review
The Coronavirus disease 2019 (COVID-19) pandemic has spread to almost all nooks and corners of the world. There are numerous potential approaches to pharmacologically fight COVID-19: small-molecule drugs, interferon therapies, vaccines, oligonucleotides, peptides, and monoclonal antibodies. Medications are being developed to target the spike, membrane, nucleocapsid or envelope proteins. The spike protein is also a critical target for vaccine development. Immunoinformatic approaches are being used for the identification of B cell and cytotoxic T lymphocyte (CTL) epitopes in the SARS-CoV-2 spike protein. Different vaccine vectors are also being developed. Chemical and physical methods such as formaldehyde, UV light or β-propiolactone are being deployed for the preparation of inactivated virus vaccine. Currently, there are many vaccines undergoing clinical trials. Even though mRNA and DNA vaccines are being designed and moved into clinical trials, these types of vaccines are yet to be approved by regulatory bodies for human use. This review focuses on the drugs and vaccines being developed against the COVID-19.
Topics: COVID-19; COVID-19 Vaccines; Drug Development; Epitopes, T-Lymphocyte; Humans; SARS-CoV-2; Spike Glycoprotein, Coronavirus
PubMed: 32950264
DOI: 10.1016/j.arcmed.2020.09.010 -
Frontiers in Microbiology 2017Traditionally, chemical agents such as formalin (FA) and β-propiolactone (BPL) have long been used for the preparation of inactivated vaccines or toxoids. It has been...
Traditionally, chemical agents such as formalin (FA) and β-propiolactone (BPL) have long been used for the preparation of inactivated vaccines or toxoids. It has been shown that FA extensively modifies vaccine antigens and thus affects immunogenicity profiles, sometimes compromising the protective efficacy of the vaccines or even exacerbating the disease upon infection. In this study, we show that natural catechins from green tea extracts (GT) can be used as an inactivating agent to prepare inactivated viral vaccines. GT treatment resulted in complete and irreversible inactivation of influenza virus as well as dengue virus. In contrast to FA that reacted extensively with multiple amino acids including lysine, a major anchor residue for epitope binding to MHC molecules, GT catechin epigallocatechin-3-gallate (EGCG) crosslinked primarily with cysteine residues and thus preserved the major epitopes of the influenza hemagglutinin. In a mouse model, vaccination with GT-inactivated influenza virus (GTi virus) elicited higher levels of viral neutralizing antibodies than FA-inactivated virus (FAi virus). The vaccination completely protected the mice from a lethal challenge and restricted the challenge viral replication in the lungs. Of note, the quality of antibody responses of GTi virus was superior to that with FAi virus, in terms of the magnitude of antibody titer, cross-reactivity to hetero-subtypes of influenza viruses, and the avidity to viral antigens. As the first report of using non-toxic natural compounds for the preparation of inactivated viral vaccines, the present results could be translated into a clinically relevant vaccine platform with improved efficacy, safety, productivity, and public acceptance.
PubMed: 29312180
DOI: 10.3389/fmicb.2017.02469