RESUMO
IgM and IgG antibodies to the SARS-CoV-2 virus are detected in subjects who have recovered from COVID-19; IgM antibodies persist in a 1/3 of infected subjects up to 12 months from the moment of the disease, while IgG antibodies are present in the vast majority of cases (97%; medium and high levels antibodies were registered in 85% of cases). By the 12th month, 40% of those who recovered still have a very high level of IgG antibodies to the S-protein (>500 BAU/ml). In the feces, urine, and blood serum of patients with long-term persistent IgM antibodies, no coronavirus antigens were detected. After vaccination with the Gam-COVID-Vac vaccine, IgG antibodies to the S-protein are detected in 100% of cases and remain at a high level for 4 months, by the 5-6th month, the level of antibodies decreases. During revaccination, the level of IgG antibodies to S-protein reaches high values earlier than during primary vaccination, and remains high for 4 months (observation period). The blood sera of recovered and vaccinated patients have a high virus-neutralizing activity (at least 1:80), while its level is somewhat higher in recovered patients.
Assuntos
Anticorpos Antivirais , COVID-19 , Humanos , Imunização Secundária , COVID-19/prevenção & controle , SARS-CoV-2 , Vacinação , Imunoglobulina M , Imunoglobulina GRESUMO
The presence of IgG and IgM antibodies in the venous blood of 76 patients with confirmed COVID-19 infection was determined by ELISA using Russian test systems. Different levels of IgM antibodies to N-protein and receptor binding domain of the Spike protein (RBD) were revealed. The dynamics of IgG antibodies to the whole virion antigen and recombinant antigens showed high values on weeks 4-5 of the disease. The level of IgG antibodies to Nprotein remained low throughout the observation period. The characteristic dynamics of IgG measured using test systems with sorbed whole virion or recombinant spike proteins reflects the duration of the disease.
Assuntos
Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , COVID-19/diagnóstico , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Glicoproteína da Espícula de Coronavírus/imunologia , Antígenos Virais/genética , COVID-19/sangue , COVID-19/imunologia , COVID-19/virologia , Proteínas do Nucleocapsídeo de Coronavírus/genética , Ensaio de Imunoadsorção Enzimática , Humanos , Imunidade Humoral , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/genética , Fatores de Tempo , Vírion/genética , Vírion/imunologiaRESUMO
The bactericidal activity of recombinant endolysins LysECD7, LysAm24, LysAp22, LysSi3 and LysSt11 was assayed in multidrug resistant strains (n=120) of Salmonella enterica, E. coli, Acinetobacter baumannii, Enterobacter spp., Pseudomonas aeruginosa, Klebsiella pneumoniae, and Campylobacter jejuni. The assay showed that the recombinant endolysins had a wide spectrum of bactericidal activity compared to endolysins of their progenitor phages. Among examined endolysins, we selected the active pharmaceutical substances with broad spectrum of bactericidal activity. Most strains were sensitive to LysECD7 (70.7%), LysAm24 (65%), and LysAp22 (58.6%), which seems to be promising causative agents for the development of finished dosage form.
Assuntos
Antibacterianos/farmacologia , Bacteriófagos/metabolismo , Endopeptidases/farmacologia , Acinetobacter baumannii/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Klebsiella pneumoniae/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacosRESUMO
Pharmacokinetics of suppository forms of bacteriophages was studied on male Chinchilla rabbits. Suppositories with various composition of bacteriophages were administered once per rectum to rabbits, and the presence of phage particles was estimated in the blood, urine, and feces over 24 h. Pharmacokinetic study showed that the phages were detected in the blood, urine, and feces at various terms of the experiment irrespective of the size of viral particles, which confirmed the possibility of their systemic effects after rectal administration. Thus, the use of suppository form of bacteriophages can ensure the presence of phage particles even in infection foci that cannot directly contact with the preparation.
