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Viruses Jan 2024Mpox virus (MPXV) infections have increased in many countries since May 2022, increasing demand for diagnostic tests and research on the virus. To ensure personnel...
Mpox virus (MPXV) infections have increased in many countries since May 2022, increasing demand for diagnostic tests and research on the virus. To ensure personnel safety, appropriate and reliable measures are needed to disinfect and inactivate infectious samples; Methods: We evaluated the stability of infectious MPXV cultures stored at different temperatures and through freeze-thaw cycles. Heat physical treatment (56 °C, 70 °C, 95 °C), chemical treatment (beta-propiolactone (BPL)) and two commercialized disinfectants (Micro-Chem Plus (MCP) and ethanol) were tested against infectious MPXV cultures; Results: The results indicated that MPXV stability increases with lower temperatures. The MPXV titer was stable within three freeze-thaw cycles and only decreased by 1.04 log (lg) 50% cell culture infective dose (CCID) per milliliter (12.44%) after twelve cycles. MPXV could be effectively inactivated at 56 °C for 40 min, 70 °C for 10 min, and 95 °C for 5 min. For BPL inactivation, a 1:1000 volume ratio (BPL:virus) could also effectively inactivate MPXV. A total of 2% or 5% MCP and 75% ethanol treated with MPXV for at least 1 min could reduce >4.25 lg; Conclusions: MPXV shows high stability to temperature and freeze-thaw. Heat and BPL treatments are effective for the inactivation of MPXV, while MCP and ethanol are effective for disinfection, which could help laboratory staff operate the MPXV under safer conditions and improve operational protocols.
Topics: Humans; Disinfection; Monkeypox virus; Disinfectants; Cell Culture Techniques; Ethanol; Propiolactone
PubMed: 38257804
DOI: 10.3390/v16010104 -
Expert Review of Vaccines 2024Vaccination is the most effective method to control the prevalence of seasonal influenza and the most widely used influenza vaccine is the inactivated influenza vaccine... (Review)
Review
INTRODUCTION
Vaccination is the most effective method to control the prevalence of seasonal influenza and the most widely used influenza vaccine is the inactivated influenza vaccine (IIV). Each season, the influenza vaccine must be updated to be most effective against current circulating variants. Therefore, developing a universal influenza vaccine (UIV) that can elicit both broad and durable protection is of the utmost importance.
AREA COVERED
This review summarizes and compares the available influenza vaccines in the market and inactivation methods used for manufacturing IIVs. Then, we discuss the latest progress of the UIV development in the IIV format and the challenges to address for moving these vaccine candidates to clinical trials and commercialization. The literature search was based on the Centers for Disease Control and Prevention (CDC) and the PubMed databases.
EXPERT OPINION
The unmet need for UIV is the primary aim of developing the next generation of influenza vaccines. The IIV has high antigenicity and a refined manufacturing process compared to most other formats. Developing the UIV in IIV format is a promising direction with advanced biomolecular technologies and next-generation adjuvant. It also inspires the development of universal vaccines for other infectious diseases.
Topics: Humans; Influenza Vaccines; Influenza, Human; Vaccines, Inactivated; Vaccination; Seasons; Antibodies, Viral
PubMed: 38509022
DOI: 10.1080/14760584.2024.2333338 -
Viruses Jun 2023Successful SARS-CoV-2 inactivation allows its safe use in Biosafety Level 2 facilities, and the use of the whole viral particle helps in the development of analytical...
Successful SARS-CoV-2 inactivation allows its safe use in Biosafety Level 2 facilities, and the use of the whole viral particle helps in the development of analytical methods and a more reliable immune response, contributing to the development and improvement of in vitro and in vivo assays. In order to obtain a functional product, we evaluated several inactivation protocols and observed that 0.03% beta-propiolactone for 24 h was the best condition tested, as it promoted SARS-CoV-2 inactivation above 99.99% and no cytopathic effect was visualized after five serial passages. Moreover, RT-qPCR and transmission electron microscopy revealed that RNA quantification and viral structure integrity were preserved. The antigenicity of inactivated SARS-CoV-2 was confirmed by ELISA using different Spike-neutralizing monoclonal antibodies. K18-hACE2 mice immunized with inactivated SARS-CoV-2, formulated in AddaS0, presented high neutralizing antibody titers, no significant weight loss, and longer survival than controls from a lethal challenge, despite RNA detection in the oropharyngeal swab, lung, and brain. This work emphasizes the importance of using different techniques to confirm viral inactivation and avoid potentially disastrous contamination. We believe that an efficiently inactivated product can be used in several applications, including the development and improvement of molecular diagnostic kits, as an antigen for antibody production as well as a control for non-clinical trials.
Topics: Mice; Animals; SARS-CoV-2; Antibody Formation; COVID-19; Antibodies, Viral; Immunization; Enzyme-Linked Immunosorbent Assay; Antibodies, Neutralizing
PubMed: 37515173
DOI: 10.3390/v15071486 -
Materials Advances Mar 2021Cowpea mosaic virus (CPMV) is currently in the development pipeline for multiple biomedical applications, including cancer immunotherapy. In particular the application...
Cowpea mosaic virus (CPMV) is currently in the development pipeline for multiple biomedical applications, including cancer immunotherapy. In particular the application of CPMV as vaccine has shown promise; here the plant viral nanoparticle is used as an adjuvant and is injected directly into a tumor to reverse immunosuppression and prime systemic anti-tumor immunity. Efficacy of this CPMV-based cancer immunotherapy has been demonstrated in multiple tumor mouse models and canine cancer patients. However, while CPMV is non-infectious to mammals, it is infectious to legumes and therefore, from a safety perspective, it is desired to develop non-infectious CPMV formulations. Non-infectious virus-like particles of CPMV devoid of nucleic acids have been produced; nevertheless, efficacy of such empty CPMV nanoparticles does not match efficacy of nucleic acid-laden CPMV. The multivalent capsid activates the innate immune system through pathogen pattern recognition receptors (PRRs) such as toll-like receptors (TLRs); the RNA cargo provides additional signaling through TLR-7/8, which boosts the efficacy of this adjuvant. Therefore, in this study, we set out to develop RNA-laden, but non-infectious CPMV. We report inactivation of CPMV using UV light and chemical inactivation using β-propiolactone (βPL) or formalin. 7.5 J cm UV, 50 mM βPL or 1 mM formalin was determined to be sufficient to inactivate CPMV and prevented plant infection. We compared the immunogenicity of native CPMV and inactivated CPMV formulations and using RAW-Blue™ reporter cells and a murine syngeneic, orthotropic melanoma model (using B16F10 cells and C57BL6 mice). While the assay indicated activation of the RAW-Blue™ reporter cells by formaldehyde and UV-inactivated CPMV at levels comparable to native CPMV; βPL-inactivated CPMV appeared to have diminished activity. Tumor mouse model experiments indicate potent efficacy of the chemically-inactivated CPMV (UV-treated CPMV was not tested) leading to tumor regression and increased survival; efficacy was somewhat reduced when compared to CPMV, however these samples outperformed the empty CPMV nanoparticles. These results will facilitate the translational development of safe and potent CPMV-based cancer immunotherapies.
PubMed: 34368764
DOI: 10.1039/D0MA00752H -
Virology Journal Oct 2020Transmissible gastroenteritis virus (TGEV) causes enteric infection in piglets, characterized by vomiting, severe diarrhea and dehydration, and the mortality in suckling...
BACKGROUND
Transmissible gastroenteritis virus (TGEV) causes enteric infection in piglets, characterized by vomiting, severe diarrhea and dehydration, and the mortality in suckling piglets is often high up to 100%. Vaccination is an effective measure to control the disease caused by TGEV.
METHODS
In this study, cell-cultured TGEV HN-2012 strain was inactivated by formaldehyde (FA), β-propiolactone (BPL) or binaryethylenimine (BEI), respectively. Then the inactivated TGEV vaccine was prepared with freund's adjuvant, and the immunization effects were evaluated in mice. The TGEV-specific IgG level was detected by ELISA. The positive rates of CD4, CD8, CD4IFN-γ, CD4IL-4 T lymphocytes were detected by flow cytometry assay. Lymphocyte proliferation assay and gross pathology and histopathology examination were also performed to assess the three different inactivating reagents in formulating TGEV vaccine.
RESULTS
The results showed that the TGEV-specific IgG level in FA group (n = 17) was earlier and stronger, while the BEI group produced much longer-term IgG level. The lymphocyte proliferation test demonstrated that the BEI group had a stronger ability to induce spleen lymphocyte proliferation. The positive rates of CD4 and CD8 T lymphocyte subsets of peripheral blood lymphocyte in BEI group was higher than that in FA group and BPL groups by flow cytometry assay. The positive rate of CD4IFN-γ T lymphocyte subset was the highest in the BPL group, and the positive rate of CD4IL-4 T lymphocyte subset was the highest in the FA group. There were no obvious pathological changes in the vaccinated mice and the control group after the macroscopic and histopathological examination.
CONCLUSIONS
These results indicated that all the three experimental groups could induce cellular and humoral immunity, and the FA group had the best humoral immunity effect, while the BEI group showed its excellent cellular immunity effect.
Topics: Animals; Antibodies, Viral; Female; Gastroenteritis, Transmissible, of Swine; Immunity, Cellular; Immunity, Humoral; Immunoglobulin G; Indicators and Reagents; Lymphocyte Activation; Mice; Mice, Inbred BALB C; Swine; T-Lymphocytes; Transmissible gastroenteritis virus; Vaccines, Inactivated; Viral Vaccines; Virus Inactivation
PubMed: 33097081
DOI: 10.1186/s12985-020-01433-8 -
Microscopy Research and Technique Feb 2022The severe COVID-19 pandemic drives the research toward the SARS-CoV-2 virion structure and the possible therapies against it. Here, we characterized the...
The severe COVID-19 pandemic drives the research toward the SARS-CoV-2 virion structure and the possible therapies against it. Here, we characterized the β-propiolactone inactivated SARS-CoV-2 virions using transmission electron microscopy (TEM) and atomic force microscopy (AFM). We compared the SARS-CoV-2 samples purified by two consecutive chromatographic procedures (size exclusion chromatography [SEC], followed by ion-exchange chromatography [IEC]) with samples purified by ultracentrifugation. The samples prepared using SEC and IEC retained more spikes on the surface than the ones prepared using ultracentrifugation, as confirmed by TEM and AFM. TEM showed that the spike (S) proteins were in the pre-fusion conformation. Notably, the S proteins could be recognized by specific monoclonal antibodies. Analytical TEM showed that the inactivated virions retained nucleic acid. Altogether, we demonstrated that the inactivated SARS-CoV-2 virions retain the structural features of native viruses and provide a prospective vaccine candidate.
Topics: Animals; COVID-19; Chlorocebus aethiops; Humans; Pandemics; Propiolactone; SARS-CoV-2; Vaccines, Inactivated; Vero Cells
PubMed: 34498784
DOI: 10.1002/jemt.23931 -
Bioorganic & Medicinal Chemistry Letters Dec 2021S-Palmitoylation is a reversible post-translational lipid modification that regulates protein trafficking and signaling. The enzymatic depalmitoylation of proteins is...
S-Palmitoylation is a reversible post-translational lipid modification that regulates protein trafficking and signaling. The enzymatic depalmitoylation of proteins is inhibited by the beta-lactones Palmostatin M and B, which have been found to target several serine hydrolases. In efforts to better understand the mechanism of action of Palmostatin M, we describe herein the synthesis, chemical proteomic analysis, and functional characterization of analogs of this compound. We identify Palmostatin M analogs that maintain inhibitory activity in N-Ras depalmitoylation assays while displaying complementary reactivity across the serine hydrolase class as measured by activity-based protein profiling. Active Palmostatin M analogs inhibit the recently characterized ABHD17 subfamily of depalmitoylating enzymes, while sparing other candidate depalmitoylases such as LYPLA1 and LYPLA2. These findings improve our understanding of the structure-activity relationship of Palmostatin M and refine the set of serine hydrolase targets relevant to the compound's effects on N-Ras palmitoylation dynamics.
Topics: Humans; Lactones; Molecular Structure; Propiolactone; Proteomics; Sulfones; ras Proteins
PubMed: 34666187
DOI: 10.1016/j.bmcl.2021.128414 -
BMC Infectious Diseases Jul 2021The main strategy to contain the current SARS-CoV-2 pandemic remains to implement a comprehensive testing, tracing and quarantining strategy until vaccination of the... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
The main strategy to contain the current SARS-CoV-2 pandemic remains to implement a comprehensive testing, tracing and quarantining strategy until vaccination of the population is adequate. Scent dogs could support current testing strategies.
METHODS
Ten dogs were trained for 8 days to detect SARS-CoV-2 infections in beta-propiolactone inactivated saliva samples. The subsequent cognitive transfer performance for the recognition of non-inactivated samples were tested on three different body fluids (saliva, urine, and sweat) in a randomised, double-blind controlled study.
RESULTS
Dogs were tested on a total of 5242 randomised sample presentations. Dogs detected non-inactivated saliva samples with a diagnostic sensitivity of 84% (95% CI: 62.5-94.44%) and specificity of 95% (95% CI: 93.4-96%). In a subsequent experiment to compare the scent recognition between the three non-inactivated body fluids, diagnostic sensitivity and specificity were 95% (95% CI: 66.67-100%) and 98% (95% CI: 94.87-100%) for urine, 91% (95% CI: 71.43-100%) and 94% (95% CI: 90.91-97.78%) for sweat, 82% (95% CI: 64.29-95.24%), and 96% (95% CI: 94.95-98.9%) for saliva respectively.
CONCLUSIONS
The scent cognitive transfer performance between inactivated and non-inactivated samples as well as between different sample materials indicates that global, specific SARS-CoV-2-associated volatile compounds are released across different body secretions, independently from the patient's symptoms. All tested body fluids appear to be similarly suited for reliable detection of SARS-CoV-2 infected individuals.
Topics: Animals; Body Fluids; COVID-19; Dogs; Humans; Odorants; Pandemics; SARS-CoV-2; Saliva
PubMed: 34315418
DOI: 10.1186/s12879-021-06411-1 -
Journal of Virological Methods Jan 2021Zika virus (ZIKV) infection remains a public health concern necessitating demand for long-term virus production for diagnostic assays and R&D activities. Inactivated...
Zika virus (ZIKV) infection remains a public health concern necessitating demand for long-term virus production for diagnostic assays and R&D activities. Inactivated virus constitutes an important component of the Trioplex rRT-PCR assay and serological IgM assay (MAC-ELISA). The aim of our study is to establish standard methods of ZIKV inactivation while maintaining antigenicity and RNA integrity. We tested viral supernatants by four different inactivation methods: 1. Heat inactivation at 56 °C and 60 °C; 2. Gamma-Irradiation; 3. Chemical inactivation by Beta-propiolactone (BPL) and 4. Fast-acting commercial disinfecting agents. Effectivity was measured by cytopathic effect (CPE) and plaque assay. RNA stability and antigenicity were measured by RT-PCR and MAC-ELISA, respectively. Results: Heat inactivation: Low titer samples, incubated at 56 °C for 2 h, showed neither CPE or plaques compared to high titer supernatants that required 2.5 h. Inactivation occurred at 60 °C for 60 min with all virus titers. Gamma irradiation: Samples irradiated at ≥3 Mrad for low virus concentrations and ≥5Mrad for high virus titer completely inactivated virus. Chemical Inactivation: Neither CPE nor plaques were observed with ≥0.045 % BPL inactivation of ZIKV. Disinfectant: Treatment of viral supernatants with Micro-Chem Plus™, inactivated virus in 2 min, whereas, Ethanol (70 %) and STERIS Coverage® Spray TB inactivated the virus in 5 min.
Topics: Disinfection; Humans; Indicators and Reagents; Virus Inactivation; Zika Virus; Zika Virus Infection
PubMed: 33098957
DOI: 10.1016/j.jviromet.2020.114004 -
International Journal of Molecular... Jan 2020[6]-Gingerol from ginger has received considerable attention as a potential cancer therapeutic agent because of its chemopreventive and chemotherapeutic effects, as well...
[6]-Gingerol from ginger has received considerable attention as a potential cancer therapeutic agent because of its chemopreventive and chemotherapeutic effects, as well as its safety. In the current study, we examined [6]-gingerol as a natural scavenger of nine ultimate chemical carcinogens to which we are frequently exposed: glycidamide, styrene oxide, aflatoxin B1 exo-8,9-epoxide, -propiolactone, ethylene oxide, propylene oxide, 2-cyanoethylene oxide, chloroethylene oxide, and vinyl carbamate epoxide. To evaluate [6]-gingerol efficacy, we expanded our research with the examination of glutathione-the strongest natural scavenger in human cells. The corresponding activation free energies were calculated using Hartree-Fock method with three flexible basis sets and two implicit solvation models. According to our results, [6]-gingerol proves to be an extremely effective scavenger of chemical carcinogens of the epoxy type. On the other hand, with the exception of aflatoxin B1 exo-8,9-epoxide, glutathione represents a relatively poor scavenger, whose efficacy could be augmented by [6]-gingerol. Moreover, our quantum mechanical study of the alkylation reactions of chemical carcinogens with [6]-gingerol and glutathione provide valuable insights in the reaction mechanisms and the geometries of the corresponding transition states. Therefore, we strongly believe that our research forms a solid basis for further computational, experimental and clinical studies of anticarcinogenic properties of [6]-gingerol as well as for the development of novel chemoprophylactic dietary supplements. Finally, the obtained results also point to the applicability of quantum chemical methods to studies of alkylation reactions related to chemical carcinogenesis.
Topics: Aflatoxin B1; Alkylation; Anticarcinogenic Agents; Carcinogens; Catechols; Cell Line; Chemoprevention; Epoxy Compounds; Ethylene Oxide; Fatty Alcohols; Zingiber officinale; Humans; Propiolactone; Urethane
PubMed: 31973096
DOI: 10.3390/ijms21030695