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Pathogens (Basel, Switzerland) May 2021The development of a safe and effective vaccine to protect against COVID-19 is a global priority due to the current high SARS-CoV-2 infection rate. Currently, there are...
The development of a safe and effective vaccine to protect against COVID-19 is a global priority due to the current high SARS-CoV-2 infection rate. Currently, there are over 160 SARS-CoV-2 vaccine candidates at the clinical or pre-clinical stages of development. Of these, there are only three whole-virus vaccine candidates produced using β-propiolactone or formalin inactivation. Here, we prepared a whole-virus SARS-CoV-2 vaccine (SARS-CoV-2 PsIV) using a novel psoralen inactivation method and evaluated its immunogenicity in mice using two different adjuvants, alum and Advax-2. We compared the immunogenicity of SARS-CoV-2 PsIV against SARS-CoV-2 DNA vaccines expressing either full-length or truncated spike proteins. We also compared the psoralen-inactivated vaccine against a DNA prime, psoralen-inactivated vaccine boost regimen. After two doses, the psoralen-inactivated vaccine, when administered with alum or Advax-2 adjuvants, generated a dose-dependent neutralizing antibody responses in mice. Overall, the pattern of cytokine ELISPOT responses to antigen-stimulation observed in this study indicates that SARS-CoV-2 PsIV with the alum adjuvant promotes a Th2-type response, while SARS-CoV-2 PsIV with the Advax-2 adjuvant promotes a Th1-type response.
PubMed: 34069575
DOI: 10.3390/pathogens10050626 -
British Journal of Cancer Dec 1982Ethylene oxide and 1,2-propylene oxide were each administered intragastrically by gavage at 2 dosages (30 and 7.5 mg/kg body wt; 60 and 15 mg/kg body wt respectively) to...
Ethylene oxide and 1,2-propylene oxide were each administered intragastrically by gavage at 2 dosages (30 and 7.5 mg/kg body wt; 60 and 15 mg/kg body wt respectively) to groups of 50 female Sprague-Dawley rats twice weekly for a period of nearly 3 years using salad oil as the solvent. Both compounds induced local tumours, mainly squamous-cell carcinomas of the forestomach, dependent on the dosage. The first tumour occurred in the 79th week both in the group treated with ethylene oxide and in that treated with 1,2-propylene oxide. The following tumour rates resulted: ethylene oxide 62 and 16%; 1,2-propylene oxide 40 and 4%. In addition carcinomata in situ, papillomas and reactive changes of the squamous epithelium of the forestomach were observed in other animals, but neither ethylene oxide nor 1,2-propylene oxide induced tumours at sites away from the point of administration.
Topics: Animals; Carcinoma in Situ; Carcinoma, Squamous Cell; Dose-Response Relationship, Drug; Epoxy Compounds; Ethers, Cyclic; Ethylene Oxide; Female; Lymph Nodes; Lymphatic Metastasis; Neoplasms, Experimental; Papilloma; Propiolactone; Rats; Rats, Inbred Strains; Stomach Neoplasms
PubMed: 7150486
DOI: 10.1038/bjc.1982.303 -
Applied Microbiology Nov 1961Twenty-five bacterial species were cultured in basal broth plus 1 of 19 different carbohydrates which were sterilized by Seitz filtration, autoclaving (112 C, 10 min),...
Twenty-five bacterial species were cultured in basal broth plus 1 of 19 different carbohydrates which were sterilized by Seitz filtration, autoclaving (112 C, 10 min), or exposure to 0.2% beta-propiolactone (BPL). No significant differences were found either in the visual observations for acid and gas, pH, or titrable acidity determinations after 3 days of incubation with any of the three preparations tested. An effort was made to further determine the effect of BPL and heat on carbohydrates by assaying for glucose before and after treatment. Results indicated that glucose was not degraded by 0.2% BPL, however, it was shown that autoclave temperatures caused extensive degradation. Statistical treatment of the results from Warburg studies indicated that BPL-treated glucose showed no appreciable toxic effects, although the actual oxygen uptake was not as great as with Seitz- or autoclave-treated glucose. The application of the BPL sterilization process was discussed.
Topics: Culture Media; Fermentation; Lactones; Propiolactone; Sterilization; Temperature
PubMed: 13907502
DOI: 10.1128/am.9.6.534-537.1961 -
The Cornell Veterinarian Jan 1982Inactivated canine parvovirus (CPV) and inactivated feline panleukopenia virus (FPV) vaccines were evaluated in dogs. Maximal serologic response occurred within 1-2...
Inactivated canine parvovirus (CPV) and inactivated feline panleukopenia virus (FPV) vaccines were evaluated in dogs. Maximal serologic response occurred within 1-2 weeks after vaccination. Antibody titers then declined rapidly to low levels that persisted at least 20 weeks. Immunity to CPV, defined as complete resistance to infection, was correlated with serum antibody titer and did not persist longer than 6 weeks after vaccination with inactivated virus. However, protection against generalized infection was demonstrated 20 weeks after vaccination. In unvaccinated dogs, viremia and generalized infection occurred after oronasal challenge with virulent CPV. In contrast, viral replication was restricted to the intestinal tract and gut-associated lymphoid tissue of vaccinated dogs. Canine parvovirus was inactivated by formalin, beta-propiolactone (BPL), and binary ethylenimine (BEI) in serum-free media; inactivation kinetics were determined. Formalin resulted in a greater loss of viral HA than either BEI of BPL, and antigenicity was correspondingly reduced.
Topics: Animals; Antibodies, Viral; Aziridines; Dogs; Dose-Response Relationship, Drug; Feline Panleukopenia Virus; Formaldehyde; Hemagglutination Inhibition Tests; Parvoviridae; Propiolactone; Vaccines, Attenuated; Viral Vaccines
PubMed: 6279359
DOI: No ID Found -
Oncotarget Feb 2016Oncogenic NRAS mutations are frequent in melanoma and lead to increased downstream signaling and uncontrolled cell proliferation. Since the direct inhibition of NRAS is...
Oncogenic NRAS mutations are frequent in melanoma and lead to increased downstream signaling and uncontrolled cell proliferation. Since the direct inhibition of NRAS is not possible yet, modulators of NRAS posttranslational modifications have become an area of interest. Specifically, interfering with NRAS posttranslational palmitoylation/depalmitoylation cycle could disturb proper NRAS localization, and therefore decrease cell proliferation and downstream signaling. Here, we investigate the expression and function of NRAS depalmitoylating acyl protein thioesterases 1 and 2 (APT-1, APT-2) in a panel of NRAS mutant melanoma cells. First, we show that all melanoma cell lines examined express APT-1 and APT-2. Next, we show that siRNA mediated APT-1 and APT-2 knock down and that the specific APT-1 and -2 inhibitors ML348 and ML349 have no biologically significant effects in NRAS mutant melanoma cells. Finally, we test the dual APT-1 and APT-2 inhibitor palmostatin B and conclude that palmostatin B has effects on NRAS downstream signaling and cell viability in NRAS mutant melanoma cells, offering an interesting starting point for future studies.
Topics: Apoptosis; Blotting, Western; Cell Proliferation; Enzyme Inhibitors; GTP Phosphohydrolases; Humans; Melanoma; Membrane Proteins; Molecular Targeted Therapy; Mutation; Propiolactone; RNA, Small Interfering; Thiolester Hydrolases; Tumor Cells, Cultured
PubMed: 26771141
DOI: 10.18632/oncotarget.6907 -
Vaccines Mar 2023Vaccines are one of the efficient means available so far for preventing and controlling the infection rate of COVID-19. Several researchers have focused on the whole...
Vaccines are one of the efficient means available so far for preventing and controlling the infection rate of COVID-19. Several researchers have focused on the whole virus's (SARS-CoV-2) inactivated vaccines which are economically efficient to produce. In Pakistan, multiple variants of SARS-CoV-2 have been reported since the start of the pandemic in February 2020. Due to the continuous evolution of the virus and economic recessions, the present study was designed to develop an indigenous inactivated SARS-CoV-2 vaccine that might help not only to prevent the COVID-19 in Pakistan, it will also save the country's economic resources. The SARS-CoV-2 were isolated and characterized using the Vero-E6 cell culture system. The seed selection was carried out using cross-neutralization assay and phylogenetic analysis. The selected isolate of SARS-CoV-2 (hCoV-19/Pakistan/UHSPK3-UVAS268/2021) was inactivated using beta-propiolactone followed by vaccine formulation using Alum adjuvant, keeping the S protein concentration as 5 μg/dose. The vaccine efficacy was evaluated by in vivo immunogenicity testing in laboratory animals and in in vitro microneutralization test. The phylogenetic analysis revealed that all the SARS-CoV-2 isolates reported from Pakistan nested into different clades, representing multiple introductions of the virus into Pakistan. The antisera raised against various isolates from different waves in Pakistan showed a varied level of neutralization titers. However, the antisera produced against a variant (hCoV-19/Pakistan/UHSPK3-UVAS268/2021; fourth wave) efficiently neutralized (1:64-1:512) all the tested SARS-CoV-2 isolates. The inactivated whole virus vaccine of SARS-CoV-2 was safe and it also elicited a protective immune response in rabbits and rhesus macaques on the 35th-day post-vaccination. The activity of neutralizing antibodies of vaccinated animals was found at 1:256-1:1024 at 35 days post-vaccination, indicating the effectiveness of the double-dose regime of the indigenous SARS-CoV-2 vaccine.
PubMed: 36992191
DOI: 10.3390/vaccines11030607 -
Journal of Bacteriology Dec 1978Transforming DNA was exposed to either beta-propiolactone or 1,3-propane sultone and then used for transformation of competent bacteria to nutritional independence from...
Transforming DNA was exposed to either beta-propiolactone or 1,3-propane sultone and then used for transformation of competent bacteria to nutritional independence from tyrosine and tryptophan (linked markers) and leucine (an unlinked marker). The ability to transform was progressively lost by the DNA during incubation with either of these two chemicals. For all three markers the inactivation curve was biphasic, with a short period of rapid inactivation followed by one characterized by a much slower rate. The overall rate of inactivation was different for all three markers and presumably was related to the size of the marker. The decrease in the transforming activity was in part due to the slower rate of penetration of alkylated DNA through the cellular membrane and its inability to enter the recipient bacteria. This decrease in the rate of cellular uptake, even for DNA eventually destined to enter the cell, began almost immediately after its exposure to the chemical and ended up with an almost complete lack of recognition of the heavily alkylated DNA by the specific surface receptors of competent cells. Such DNA attached to sites on the surface of competent bacteria which were different from receptors specific for the untreated nucleic acid. This attachment was not followed by uptake of the altered DNA. Presence of albumin during the incubation with a carcinogen further increased the degree of inactivation, indicating that the artificial nucleoproteins produced under such conditions were less efficient in the transformation assay than was the naked DNA. Cotransfomration of close markers progressively decreased, beginning immediately after the start of incubation of DNA with the chemicals. Extensively alkylated DNA fractionated by sedimentation through sucrose density gradients showed a peculiar distribution of cotransforming activity for such markers; namely, molecules larger than the bulk of DNA ("megamolecules") showed less ability to transform the second marker than did some of the apparently smaller molecules which sedimented more slowly through the gradient. An increase in cotransformation of distant markers was evident in DNA molecules after a short exposure to an alkylating agent, but cotransformation of such markers was absent in DNA treated for longer periods. The observed changes in the transforming and cotransforming activities of the alkylated DNA can be explained by what is known about the physicochemistry of such DNA and in particular about the propensity of the alkylated and broken molecules to form complexes with themselves and with other macromolecules.
Topics: Alkylating Agents; Alkylation; Bacillus subtilis; DNA, Bacterial; Lactones; Propiolactone; Serum Albumin, Bovine; Thiophenes; Transformation, Bacterial
PubMed: 102637
DOI: 10.1128/jb.136.3.854-866.1978 -
Journal of Virology Jun 1981Bovine leukemia virus (BLV) from either persistently infected bat cells or fetal lamb kidney cells induced rapid syncytium formation in F81 indicator cells. Distinct...
Bovine leukemia virus (BLV) from either persistently infected bat cells or fetal lamb kidney cells induced rapid syncytium formation in F81 indicator cells. Distinct syncytia were seen within 2 h after inoculation of cells with highly concentrated (500-fold) cell-free BLV preparations and within 4 to 8 h when unconcentrated cell-free BLV preparations were used. Indicator cell densities of 1 x 10(5) to 2 x 10(5) were optimal for rapid and maximal syncytium formation. Pretreatment of BLV with reference BLV leukemic serum and antiserum prepared against purified BLV significantly inhibited (95%) syncytium formation. Reference bovine viral diarrhea virus serum, foamy-like bovine syncytial virus serum, and control serum had little effect (17% inhibition). Antiserum to BLV gp51 inhibited syncytium formation by greater than 96%, whereas antiserum to BLV p24 reduced syncytium activity to a much lesser extent (38% inhibition). Treatment of BLV with beta-propiolactone (0.005 to 0.05%) had little or no effect upon syncytium-forming activity, whereas UV irradiation (15 ergs/mm(2) per s for 30 min) reduced, but did not completely destroy, the fusion activity. However, both beta-propiolactone and UV irradiation drastically reduced the replication potential of BLV, as demonstrated by the lack of p24 expression in the inoculated cells. Concentrations of cycloheximide, cytosine arabinoside, tunicamycin, and 2-deoxy-D-glucose which effectively blocked cellular macromolecular synthesis did not significantly inhibit syncytium formation. These latter results suggested that de novo protein and DNA synthesis as well as protein glycosylation were not required for early syncytium formation. Thus, these experiments demonstrated that replication of BLV by the indicator cells was not essential for cell fusion.
Topics: Animals; Cell Fusion; Cell Line; Cycloheximide; Cytarabine; Cytopathogenic Effect, Viral; Deoxyglucose; Kinetics; Leukemia Virus, Bovine; Propiolactone; Retroviridae; Tunicamycin; Ultraviolet Rays
PubMed: 6264150
DOI: 10.1128/JVI.38.3.1055-1063.1981 -
BMC Research Notes Jul 2018Infection of chickens with low pathogenic avian influenza virus, such as H9N2 virus, culminates in decreased egg production and increased mortality and morbidity if...
OBJECTIVE
Infection of chickens with low pathogenic avian influenza virus, such as H9N2 virus, culminates in decreased egg production and increased mortality and morbidity if co-infection with other respiratory pathogens occurs. We have previously observed the induction of antibody- and cell-mediated immune responses after intramuscular administration of an H9N2 beta-propiolactone inactivated virus vaccine to chickens. Given the fact that in ovo vaccination represents a practical option for vaccination against H9N2 AIV in chickens, in the current study, we set out to characterize immune responses in chickens against a beta-propiolactone inactivated H9N2 virus vaccine after primary vaccination in ovo on embryonic day 18, and secondary intramuscular vaccination on day 14 post-hatch. We also included the Toll-like receptor 21 ligand, CpG ODN 2007, and an oil emulsion adjuvant, AddaVax™, as adjuvants for the vaccines.
RESULTS
Antibody-mediated immune responses were observed after administering the secondary intramuscular vaccine. Cell-mediated immune responses were observed in chickens that received the beta-propiolactone inactivated H9N2 virus combined with AddaVax™. Our results demonstrate that adaptive immune responses can be induced in chickens after a primary in ovo vaccination and secondary intramuscular vaccination.
Topics: Animals; Antibodies, Viral; Antibody Formation; Chickens; Influenza A Virus, H9N2 Subtype; Influenza Vaccines; Influenza in Birds
PubMed: 29970157
DOI: 10.1186/s13104-018-3537-9 -
Genetics Dec 1974Two genes, rad6 and rad9, that confer radiation sensitivity in the yeast Saccharomyces cerevisiae also greatly reduce the frequency of chemically-induced reversions of a...
Two genes, rad6 and rad9, that confer radiation sensitivity in the yeast Saccharomyces cerevisiae also greatly reduce the frequency of chemically-induced reversions of a tester mutant cyc1-131, which is a chain initiation mutant in the structural gene determining iso-1-cytochrome c. Mutations induced by ethyl methanesulfonate (EMS), diethyl sulfate (DES), methyl methanesulfonate (MMS), dimethyl sulfate (DMS), nitroquinoline oxide (NQO), nitrosoguanidine (NTG), nitrogen mustard (HN2), beta-propiolactone, and tritiated uridine, as well as mutations induced by ultraviolet light (UV) and ionizing radiation were greatly diminished in strains homozygous for either the rad6 or rad9 gene. Nitrous acid and nitrosoimidazolidone (NIL), on the other hand, were highly mutagenic in these repair-deficient mutants, and at low doses, these mutagens acted with about the same efficiency as in the normal RAD strain. At high doses of either nitrous acid or NIL, however, reversion frequencies were significantly reduced in the two rad mutants compared to normal strains. Although both rad mutants are immutable to about the same extent, the rad9 strains tend to be less sensitive to the lethal effect of chemical mutagens than rad6 strains. It is concluded that yeast requires a functional repair system for mutation induction by chemical agents.
Topics: Cytochrome c Group; DNA Repair; DNA Replication; Drug Resistance, Microbial; Genes; Mechlorethamine; Mesylates; Mutagens; Mutation; Nitrosoguanidines; Nitrous Acid; Peptide Chain Initiation, Translational; Quinolines; Radiation Genetics; Saccharomyces cerevisiae; Sulfates; Tritium; Uridine
PubMed: 4376097
DOI: 10.1093/genetics/78.4.1101