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1.
Vet Microbiol ; 271: 109491, 2022 Aug.
Article in English | MEDLINE | ID: covidwho-1882620

ABSTRACT

Viral infectious pathogens, such as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza virus, can cause extremely high infection rates and mortality in humans. Therefore, it is urgent to develop an effective vaccine against coronavirus and influenza virus infection. Herein, we used the influenza virus as a vector to express the SARS-CoV-2 spike receptor-binding domain (RBD) and hemagglutinin-esterase-fusion (HEF) protein of the influenza C virus. We then evaluated the feasibility and effectiveness of this design strategy through experiments in vitro and in vivo. The results showed that the chimeric viruses could stably express the HEF protein and the SARS-CoV-2 spike RBD at a high level. BALB/c mice, infected with the chimeric virus, exhibited mild clinical symptoms, yet produced high specific antibody levels against RBD and HEF, including neutralizing antibodies. Importantly, high neutralizing antibodies could be retained in the sera of mice for at least 20 weeks. Altogether, our data provided a new strategy for developing safe and effective COVID-19 and influenza virus vaccines.


Subject(s)
COVID-19 Vaccines , COVID-19 , Influenza Vaccines , Orthomyxoviridae , Animals , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , COVID-19/prevention & control , COVID-19 Vaccines/immunology , Influenza Vaccines/immunology , Mice , Mice, Inbred BALB C , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus
2.
Viruses ; 14(4)2022 03 30.
Article in English | MEDLINE | ID: covidwho-1834926

ABSTRACT

The H9N2 subtype avian influenza viruses (AIVs) have been circulating in China for more than 20 years, attracting more and more attention due to the potential threat of them. At present, vaccination is a common prevention and control strategy in poultry farms, but as virus antigenicity evolves, the immune protection efficiency of vaccines has constantly been challenged. In this study, we downloaded the hemagglutinin (HA) protein sequences of the H9N2 subtype AIVs from 1994 to 2019 in China-with a total of 5138 sequences. The above sequences were analyzed in terms of time and space, and it was found that h9.4.2.5 was the most popular in various regions of China. Furthermore, the prevalence of H9N2 subtype AIVs in China around 2006 was different. The domestic epidemic branch was relatively diversified from 1994 to 2006. After 2006, the epidemic branch each year was h9.4.2.5. We compared the sequences around 2006 as a whole and screened out 15 different amino acid positions. Based on the HA protein of A/chicken/Guangxi/55/2005 (GX55), the abovementioned amino acid mutations were completed. According to the 12-plasmid reverse genetic system, the rescue of the mutant virus was completed using A/PuertoRico/8/1934 (H1N1) (PR8) as the backbone. The cross hemagglutination inhibition test showed that these mutant sites could transform the parental strain from the old to the new antigenic region. Animal experiments indicated that the mutant virus provided significant protection against the virus from the new antigenic region. This study revealed the antigenic evolution of H9N2 subtype AIVs in China. At the same time, it provided an experimental basis for the development of new vaccines.


Subject(s)
Influenza A Virus, H1N1 Subtype , Influenza A Virus, H9N2 Subtype , Influenza in Birds , Amino Acids/genetics , Animals , Chickens , China/epidemiology , Evolution, Molecular , Hemagglutinin Glycoproteins, Influenza Virus/genetics , Hemagglutinins/genetics , Influenza A Virus, H9N2 Subtype/genetics , Phylogeny
3.
Acta Pharmacol Sin ; 42(12): 2155-2172, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1209738

ABSTRACT

LianhuaQingwen capsule, prepared from an herbal combination, is officially recommended as treatment for COVID-19 in China. Of the serial pharmacokinetic investigations we designed to facilitate identifying LianhuaQingwen compounds that are likely to be therapeutically important, the current investigation focused on the component Glycyrrhiza uralensis roots (Gancao). Besides its function in COVID-19 treatment, Gancao is able to induce pseudoaldosteronism by inhibiting renal 11ß-HSD2. Systemic and colon-luminal exposure to Gancao compounds were characterized in volunteers receiving LianhuaQingwen and by in vitro metabolism studies. Access of Gancao compounds to 11ß-HSD2 was characterized using human/rat, in vitro transport, and plasma protein binding studies, while 11ß-HSD2 inhibition was assessed using human kidney microsomes. LianhuaQingwen contained a total of 41 Gancao constituents (0.01-8.56 µmol/day). Although glycyrrhizin (1), licorice saponin G2 (2), and liquiritin/liquiritin apioside (21/22) were the major Gancao constituents in LianhuaQingwen, their poor intestinal absorption and access to colonic microbiota resulted in significant levels of their respective deglycosylated metabolites glycyrrhetic acid (8), 24-hydroxyglycyrrhetic acid (M2D; a new Gancao metabolite), and liquiritigenin (27) in human plasma and feces after dosing. These circulating metabolites were glucuronized/sulfated in the liver and then excreted into bile. Hepatic oxidation of 8 also yielded M2D. Circulating 8 and M2D, having good membrane permeability, could access (via passive tubular reabsorption) and inhibit renal 11ß-HSD2. Collectively, 1 and 2 were metabolically activated to the pseudoaldosterogenic compounds 8 and M2D. This investigation, together with such investigations of other components, has implications for precisely defining therapeutic benefit of LianhuaQingwen and conditions for its safe use.


Subject(s)
Antiviral Agents/pharmacokinetics , COVID-19/drug therapy , Drugs, Chinese Herbal/pharmacokinetics , Phytochemicals/pharmacokinetics , 11-beta-Hydroxysteroid Dehydrogenase Type 2/antagonists & inhibitors , 11-beta-Hydroxysteroid Dehydrogenase Type 2/metabolism , Administration, Oral , Animals , Antiviral Agents/administration & dosage , Antiviral Agents/adverse effects , Biological Availability , Biotransformation , Capsules , Drugs, Chinese Herbal/administration & dosage , Drugs, Chinese Herbal/adverse effects , Female , Glycyrrhiza/adverse effects , HEK293 Cells , Humans , Liddle Syndrome/chemically induced , Liddle Syndrome/enzymology , Male , Patient Safety , Phytochemicals/administration & dosage , Phytochemicals/adverse effects , Rats, Sprague-Dawley , Risk Assessment
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