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This study compares the serological antibody level post-COVID-19 vaccine among healthy subjects and psychiatric patients on antidepressant therapy. It also examines the difference in antidepressants' side effects experienced by psychiatric patients following the completion of two vaccine doses. A comparative posttest quasi-experimental study was conducted among healthy subjects and psychiatric patients on antidepressant medication in a teaching hospital in Malaysia. Elecsys Anti-SARS-CoV-2 assay was used to detect the antibody titre between weeks 4 and 12 post vaccination. The antidepressant side-effect checklist (ASEC) was used to monitor the occurrence of antidepressant-related side effects pre-and post-vaccination. 24 psychiatric patients and 26 healthy subjects were included. There was no significant difference in the antibody level between the patients (median = 1509 u/ml) and the healthy subjects (median = 995 u/ml). There was no significant worsening in the antidepressant-related side effects. The antibody level post-COVID-19 vaccine did not differ significantly between patients on antidepressant therapy and healthy subjects. Additionally, there was no change in the antidepressant side effects experienced by the patients following the completion of the vaccine.Copyright © 2022, Research Trends (P) LTD.. All rights reserved.
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Introduction In this study, we aimed to monitor anti-spike and anti-nucleocapsid antibodies positivity in healthcare workers (HCWs) vaccinated with two doses of inactivated CoronaVac (Sinovac, China) vaccine. Methods Overall, 242 volunteer HCWs were included. Of the participants, 193 were HCWs without history of prior documented COVID-19 (Group 1), while 49 had history of prior documented COVID-19 before vaccination (Group 2). The participants were followed up for SARS-CoV-2 antibodies positivity at four different blood sampling time points (immediately before the second vaccine dose and at the 1st, 3rd months and 141-150 days after the second dose). We investigated the serum IgG class antibodies against SARS-CoV-2 RBD region and IgG class antibodies against SARS-CoV-2 nucleocapsid antigen by chemiluminescent microparticle immunoassay (CMIA) method using commercial kits. Results We found positive serum anti-RBD IgG antibody in 76.4% of the participants (71% in Group 1;98% in Group 2) 28 days after the first dose. When the antibody levels of the groups were compared at the four blood sampling time points, Group 2 anti-RBD IgG levels were found to be significantly higher than those in Group 1 at all follow-up time points. Although anti-RBD IgG positivity persisted in 95.6% of all participants in the last blood sampling time point, a significant decrease was observed in antibody levels compared to the previous blood sampling time point. Anti-nucleocapsid IgG antibody was positive in 12 (6.2%) of participants in Group 1 and 32 (65.3%) in Group 2 at day 28 after the first dose. At the fourth blood sampling time point, anti-nucleocapsid antibodies were found to be positive in a total of 20 (9.7%) subjects, 10 (6.1%) in Group 1 and 10 (23.8%) in Group 2. Conclusions In this study, it was determined that serum antibody levels decreased in both groups after the third month after the second dose in HCWs vaccinated with CoronaVac vaccine.Copyright © GERMS 2022.
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Background: With the COVID-19 vaccine now available, there have been occasional reports of post-vaccination neurological complications. Case presentation: In this report, we present a case of neuromyelitis optica spectrum disorder (NMOSD) that developed one month after the patient received the second dose of BIBP COVID-19 vaccine (SARS-CoV-2-Vaccine [Vero Cell] Inactivated). The patient presented with itching, numbness in the hand and right side of the face, as well as nausea, vomiting, and hiccups. Brain MRI revelead lesions in the area postrema, medulla, and bilateral hypothalamus, which are typical of NMOSD. Serum antibodies to anti-AQP4 and anti-MOG were negative. Conclusion(s): The pathogenesis of NMOSD development after vaccination is still unknown. NMOSD is generally aggressive and disabling, it is important for the neurologist to be attentive to the highly variable clinical presentation after COVID-19 vaccination for early diagnosis and effective treatment.Copyright © 2023
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Background: Transient viremia has been reported after COVID-19 mRNA vaccination in ART-suppressed PWH, suggesting a stimulatory effect on the HIV reservoir. A recent study also reported that Nef-specific CD8+ T cells increased and acquired granzyme-B effector function following COVID-19 mRNA vaccination, and that this correlated with markers of immune-mediated suppression of HIV-transcribing cells. That study however did not investigate HIV viremia, nor did it detect significant reservoir size changes in the 13 participants assessed. We investigated changes in HIV viremia and reservoir size following COVID-19 mRNA vaccination in 62 ART-treated PWH. Method(s): Participants (55 male;7 female) were sampled pre-vaccination, and one month after the first and second doses. Plasma HIV loads (pVL) were measured using the Cobas 6800 (LLOQ 20 copies/mL). Intact and total HIV copies/million CD4+ T cells were measured using the Intact Proviral DNA Assay. Anti-SARS-CoV-2 S serum antibody concentrations were measured using the Roche Elecsys Anti-S assay. Result(s): Pre-vaccination, 82% of participants had pVL < 20 copies/mL (max 110 copies/mL). No significant changes in pVL were observed post-vaccination (all p >0.4): one month post-first and second doses, 79% and 85% of participants had pVL < 20 copies/mL (max 183 and 79 copies/mL), respectively. Pre-vaccination, the median intact reservoir size was 80 (IQR:28-197;n=46) HIV copies/million CD4+ T cells. Intact reservoir size did not change significantly post-vaccination (all p >0.2): one month post-first and second doses, medians were 85 (IQR: 29-184;n=46) and 65 (IQR:22-168;n=29) copies/million CD4+ T cells, respectively. No significant changes in total, nor 5' and 3' defective proviral burdens were observed post-vaccination (all p >0.1), nor were any significant changes observed in any outcome upon stratification by sex, COVID-19 vaccine regimen, or ART regimen (here, multiple tests were addressed using q-values). Finally, no correlations were observed between the SARS-CoV-2 anti-S antibody response magnitude, and either the magnitude of change in reservoir size, nor the observation of detectable viremia, following the first and second vaccine doses (all p >0.2). Conclusion(s): Despite evidence that COVID-19 mRNA vaccination may induce HIV-specific immune responses, we observed no measurable changes in reservoir size nor lasting plasma viremia following COVID-19 mRNA immunization, regardless of anti-SARS-CoV-2 antibody response magnitude. (Figure Presented).
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Some of the first immunological experiments of the 20th century-on antibody feedback inhibition-demonstrated that past exposure does not merely expedite the humoral response to secondary challenges but, rather, alters the nature of that response. Despite this history, the mechanisms underpinning these classic observations and their relationship to modern vaccine design remain obscure. Circulating antibodies produced during a primary challenge can have enhancing or, conversely, inhibitory effects on later humoral responses. Using preclinical vaccine models, we dissected this apparent contradiction to find that the interaction between serum antibodies and the entry of cognate naive B cell lineages to germinal centers was determined by the interplay of breadth, affinity, and titer. Epitope-focused vaccine designs for HIV-1 elicit circulating antibodies capable of entirely obstructing their cognate naive B cells, with important implications for the ongoing design of boostphase immunogens. Conversely, SARS-CoV receptor binding domain (RBD) immunization elicits a polyclonal serum response that enhances the proportion of high-affinity cognate B cells in germinal centers, providing a partial explanation for the effectiveness of current boost protocols but also presaging diminishing returns unless new epitopes are introduced. The resolution of these surface-level contradictions points toward a unified interactive model and emphasizes that, to move vaccinology forward, the basic biology of the humoral immune system cannot remain a black box.
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Introduction: Generating adequate cellular and humoral responses are essential principle of vaccination. Immune system of renal transplant recipient remained compromised and speculated to less likely to develop antibody after vaccination. SARS-CoV-2 neutralizing antibody after anti-SARS-CoV-2 vaccination is required for the protection from subsequent viral infection. During COVID-19 disease, anti-SARS-CoV-2 specific antibody formation was correlated with the inflammatory cytokines level. Although, there is limited informations about serum cytokines and antibody formation after COVAXINTM, COVISHIELDTM vaccination in RTRs. Therefore, in the current study, we have evaluated the inflammatory cytokines response and anti-SARS-CoV-2 specific antibody formation in renal transplant recipient. Method(s): In this study, we have recruited 171 live-related renal transplant recipients vaccinated with two doses of either COVAXINTM (whole inactivated virus-based vaccine) or COVISHIELDTM (Simian adenovirus containing full-length spike protein-based vaccine). A 5 ml blood sample was collected after two weeks of 2nd dose of vaccination. The serum was separated and stored at -200C till the analysis. Anti-SARS-CoV-2 spike protein-specific IgG antibody titer was determined by chemiluminescent microparticle immunoassay methods and Cytokines IL-10, TGF-beta, IFN-gamma, IL-6 were measured by the ELISA techniques. Result(s): The overall anti-SARS-CoV-2 spike protein specific seroconversion after vaccination was observed in 149/171(87.13%) of RTRs with median IgG titer in seroconversion group 1191.90 (IQR, 398.70-2652.45) au/ml. The median and interquartile serum cytokines IL-10 level in seroconversion (n=149) vs non-seroconversion (n=22) group was 88.89 (IQR, 55.5-125.92) vs 92.59 (IQR, 48.14-148.14) pg/ml. The median TGF-beta level in seroconversion vs non-seroconversion group was 692.10 (IQR, 446.05-927.63) vs 1001.31 (IQR, 813.15-1125.65) pg/ml. The median IL-6 level in seroconversion vs non-seroconversion group was 46.66 (33.3-66.66) vs 28.33 (16.66-34.16) pg/ml. The median IFN-gamma level in seroconversion vs non-seroconversion group was 98.0 (IQR, 57.40-111.60) vs 50.0 (IQR, 30.55-52.55) pg/ml. The cytokines IL-6 and IFN-gamma level was positively correlated with anti-SARS-CoV-2 specific protein antibody titer (r=0.192;p=0.012), IFN-gamma (r=0.188;p=0.014). TGF-beta and IL-10 were negatively correlated with anti-SARS-CoV-2 specific protein antibody titer. For IL-10 (r=-0.065;p=0.39), for TGF-beta (r=-0.246;p=0.002). Further IFN-gamma was negatively correlated with TGF-beta (r=-0.268;p<0.001). Conclusion(s): Higher pro-inflammatory cytokines (IL-6, IFN-gamma) levels were associated with anti-SARS-CoV-2 spike protein-specific seroconversion, whereas higher anti-inflammatory cytokines IL-10 and TGF-beta were negatively associated with seroconversion after vaccination in renal transplant recipients. No conflict of interestCopyright © 2023
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Since December 2019 the world has been dealing with a severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) pandemic. The first SARS-CoV-2 vaccine was made available in Europe at the end of 2020. 202 volunteers from the vicinity of the University of Applied Sciences Wiener Neustadt took part in this study;their IgG levels recognizing the RBD of SARS-CoV-2 were determined. The aim was to evaluate the SARS-CoV-2 titer levels of vaccinated, recovered and vaccinated plus recovered persons. We could show that there is a significant difference in the antibody levels of vaccinated, vaccinated plus recovered and only recovered probands. Additionally, the highest antibody levels were found in triple vaccinated persons. Furthermore, the Moderna vaccine seems to have a higher immune response.Copyright © 2022
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Rationale: To establish a novel SARS-CoV-2 human challenge model enabling controlled investigation of pathogenesis, correlates of protection and efficacy testing of interventions. Method(s): Thirty-six healthy 18-29-year-old subjects, without evidence of previous infection or vaccination, received 10 TCID50 of a wild-type virus (SARS-CoV-2/human/GBR/484861/2020) intranasally. Following inoculation, subjects resided in a high-containment quarantine, with 24-hour medical monitoring. The study's main objectives were to identify a virus dose that induced well-tolerated infection in >50% of subjects and assess virus and symptoms over time. AEs and longitudinal disease profiles are presented. Result(s): Eighteen of thirty-four evaluable (~53%) subjects became infected and developed serum antibodies. Viral load rose steeply and peaked ~5 days post-inoculation (PI). Virus was first detected in the throat but rose to significantly higher levels in the nose, peaking at ~8.87 log10 copies/ml (median, 95% CI [8.41,9.53]). Viable virus was recoverable from the nose up to ~10 days PI, on average. Mild-to-moderate symptoms were reported by 16 (89%) infected subjects, beginning 2-4 days PI. Anosmia or dysosmia developed in 15 (83%) subjects. Results from lateral flow tests were associated with viable virus and modelling showed that twice-weekly rapid antigen tests could diagnose infection before 70-80% of viable virus had been generated. There were no overt lung function changes, CT abnormalities, or SAEs. Conclusion(s): This novel SARS-CoV-2 challenge of 18-29-year-olds was considered safe. Viral kinetics over the course of primary infection was established, with implications for public health recommendations and strategies to impact transmission.
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Objectives: Administration of the third dose of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccine was initiated on December 1, 2021, in Japan. However, data on the long-term effects of this third vaccination remain scarce. Here, we examined the levels of SARS-CoV-2 antibodies in those who received the Pfizer BioNTech (BNT162b2) vaccine, 6 months after the third vaccination. Method(s): Samples from 40 healthy volunteers were used to measure SARS-CoV-2 antibodies with chemiluminescent assays against the receptor-binding domain (RBD) of the virus. Result(s): At 445 days after the first dose of BNT162b2, which is 180 days after the third vaccination, the mean anti-RBD IgG level was 159.4 AU/mL (SD 100.1 AU/mL), which was significantly higher than 144 days after the second vaccination, while mean anti-RBD IgM was baseline level (0.4 C.O.I.). The decline in IgG, 180 days after the third vaccination, was 74.1% (SD 16.1%), which was significantly lower than the 88.6% (SD 4.4%) decline observed 144 days after the second vaccination. Furthermore, we revealed that the reduction in IgG from 14 to 180 days after the third vaccination showed a significant inverse correlation with age, and the higher antibody response in younger participants at 14 days after the third vaccination disappeared at longer time points. Conclusion(s): The long-term durability of the IgG titer was significantly higher following the third vaccination compared with the second vaccination, and the reduction in IgG titer after the third vaccination inversely correlated with age.Copyright © 2022 the author(s), published by De Gruyter, Berlin/Boston.
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Despite the rapid accumulation of facts about the humoral immune response in COVID-19, there are still no evidence-based answers to questions about the factors influencing the level and duration of the detection period of antibodies to SARS-CoV-2 in the blood. Objective(s): To assess the prevalence, clinical and demographic associations of IgG antibodies to RBD of the SARSCoV-2 spike protein at different times after COVID-19. Materials and methods. Residents of the Altai region of Russia, Caucasians aged 20-93 years, who had COVID-19 from May 2020 to February 2021 (n = 314), took part in a onetime observational study. The level of antibodies in the blood was measured by enzyme-linked immunosorbent assay 1-14 months after the onset of the clinical manifestation of CO-VID-19. Results. Anti-RBD IgG antibodies of the SARS-CoV-2 spike protein were detected in 86.9% of the study participants. The dependence of the antibody titer on the duration of the period after COVID-19 was not revealed. The antibody titer was positively correlated with the complication of CO-VID-19 pneumonia and the volume of lung tissue lesions. The presence of pneumonia COVID-19 and the volume of lung tissue lesions are positively associated with age. Age positively correlated with antibody titer regardless of the pneumonia COVID-19 in the anamnesis. Conclusion. IgG antibodies to RBD of the SARS-CoV-2 spike protein are present in most of the COVID-19 patients. The titer of these antibodies in adults depends on age, complications of pneumonia COVID-19, and probably persists up to 14 months after the first symptoms of infection appear.Copyright © 2022 Interregional public organization Association of infectious disease specialists of Saint-Petersburg and Leningrad region (IPO AIDSSPbR). All rights reserved.
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In November 2020, the Armed Forces of the Russian Federation began mass immunisation of the personnel with Gam-COVID-Vac (Sputnik V), the first Russia vaccine against the new coronavirus infection (COVID-19). Thus, it became necessary to assess post-vaccination antibody levels and the duration and intensity of humoral immunity to COVID-19. The aim of the study was to investigate the immunogenicity and efficacy of Gam-COVID-Vac in military medical staff after vaccination. Material(s) and Method(s): the authors determined the presence of specific antibodies in the serum of individuals immunised with Gam-COVID-Vac (477 volunteers) and COVID-19 convalescents (73 patients), using virus neutralisation (VN), enzyme-linked immunosorbent assay (ELISA) with reagent kits by several manufacturers, and immunoblotting. The results of the study were evaluated using analysis of variance. Result(s): VN detected virus neutralising antibodies in 90.7% of vaccinated subjects;ELISA, in 95.4%. Both VN and ELISA showed lower antibody levels in the vaccinated over 50 years of age. ELISA demonstrated a significantly higher concentration of anti-SARS-CoV-2 spike IgG in the Gam-COVID-Vac group than in the COVID-19 convalescent group. The correlation between antibody detection results by VN and ELISA was the strongest when the authors used their experimental reagent kit for quantitative detection of virus neutralising antibodies by competitive ELISA with the recombinant human ACE2 receptor. Having analysed the time course of neutralising antibody titres, the authors noted a significant, more than two-fold decrease in geometric means of the titres three months after administration of the second vaccine component. Conclusion(s): the subjects vaccinated with Gam-COVID-Vac gain effective humoral immunity to COVID-19. The decrease in titres indicates the need for revaccination in 6 months.Copyright © 2023 Safety and Risk of Pharmacotherapy. All rights reserved.
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Background: Accurate measurement of antibodies is a necessary tool for assessing exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and facilitating an understanding of the role antibodies play in overall immunity. Most available assays are qualitative in nature and employ a threshold to determine the presence of antibodies, however some-quantitative assays are now available. Using cross-sectional data collected as part of an ongoing longitudinal cohort study, we aim to assess the seroprevalence of SARSCoV-2 antibodies using the Abbott AdviseDX SARS-CoV-2 IgG II (anti-S) assay and compare these results to previously measured seroprevalence of anti-nucleoprotein (anti-N) IgG in this cohort of health care workers (HCWs) at an academic medical center in Boston. Method(s): A total of 1,743 HCWs at Boston Medical Center (BMC) provided serum samples that were analyzed for SARS-CoV-2 anti-S IgG and IgM using the Abbott AdviseDx SARS-CoV-2 IgG II and Abbott AdviseDx SARS-CoV-2 IgM assay, respectively. These results were compared to previously assessed anti-N IgG seroprevalence. Precision, linearity, and positive and negative concordance with prior reverse transcription-polymerase chain reaction (RT-PCR) test were evaluated for the anti-S IgG II assay. Seroprevalence and its association with demographic variables was also assessed. Result(s): Linearity and precision results were clinically acceptable. The anti-S IgG positive and negative concordance with RT-PCR results were 88.2% (95% CI: 79.4-94.2%) and 97.4% (95% CI: 95.2-98.8%), respectively. Overall, 126 (7.2%) of 1,743 participants were positive for anti-S IgG. The original agreement in this population with the qualitative, anti-N IgG assay was 70.6%. Upon optimizing the threshold from 1.4 to 0.49 signal to cut-off ratio (S/CO) of the anti-N IgG assay, the positive agreement of the assay increased to 84.7%. Conclusion(s): The anti-S IgG II assay demonstrated reproducible and reliable measurements. Higher anti-S IgG to anti-N IgG seroprevalence highlights the present differences between serum antibodies to different epitopes of the SARS-CoV-2 virus. Further, the greater seroprevalence of anti-S IgG compared to positive RT-PCR results points to a potential for asymptomatic infection among this group of HCWs. Our results also highlight the potential utility in optimizing thresholds of the qualitative SARS-CoV-2 anti-N IgG assay for better agreement with the anti-S IgG II assay by the same vendor.Copyright © 2022 by the Author(s).
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Melioidosis is a particularly dangerous infection with endemic distribution caused by the Gram-negative microorganism from the pathogenicity group II Burkholderia pseudomallei. In endemic countries, melioidosis holds one of the leading places in mortality rate after HIV, tuberculosis and, in recent years, COVID-19. The natural ecological pathogen niches are located in tropical and subtropical climate zones, primarily in Southeast Asia and Australia, where its existence as a species is maintained in moist soil and water in a certain temperature environmental range. However, at present, more and more often cases of melioidosis are registered outside endemic territories, which emphasizes the relevance of improving the means and methods of laboratory diagnostics of this disease both for countries located in the zone of natural foci as well as for local healthcare of the countries after importation of this poorly known infection into their territory. In such countries, including the Russian Federation, the population has no natural immunity to the pathogen, and therefore this infection acquires even greater clinical and epidemiological significance. In the Volgograd Plague Control Research Institute, an erythrocyte antigenic melioidosis diagnostic agent for IHA was designed allowing to detect the presence of serum melioidosis antibodies. The diagnostic agent was obtained on the basis of a biological carrier - ram erythrocytes sensitized with isolated protein antigenic complexes of B. pseudomallei. The high analytical characteristics of the diagnostic agent were confirmed on sera models of immunized and recovering experimental animals. Using the obtained set of reagents, the level of serum antibodies against the causative agent of melioidosis was studied in residents from the 3 provinces of Vietnam (Ha Giang, Lang Son and Quang Ninh), as well as in control group composed of residents of the Volgograd region. In samples obtained from a non-endemic region, not more than 25% of cases contained IHA titers at lower than 1:10 dilution, which is apparently due to cross-reactivity of serum immunoglobulins. Positive serum samples from clinically healthy residents of Ha Giang, Lang Son and Quang Ninh provinces were at a titer of 1:10 detected in 71.5%, in dilutions of 1:20-1:80 - in 28.5% of cases. Thus, we believe that serum antibody titer of 1:80 established in the IHA results, has a diagnostic significance, reflecting the intensity of the anti-melioidosis populational immunity.Copyright © 2022 Saint Petersburg Pasteur Institute. All rights reserved.
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Introduction: Covid-19 epidemic results from an infection caused by SARS-CoV2. Evolution-based analyses on the nucleotide sequences show that SARS-CoV2 is a member of the genus Beta-coronaviruses and its genome consists of a single-stranded RNA, encoding 16 proteins. Among the structural proteins, the nucleocapsid is the most abundant protein in virus structure, highly immunogenic, with sequence conservatory. Due to a large number of mutations in the spike protein, the aim of this study was to investigate bioinformatics, expression of nucleocapsid protein and evaluate its immunogenicity as an immunogenic candidate Material(s) and Method(s): B and T cell epitopes of nucleocapsid protein were examined in the IEDB database. The PET28a-N plasmid was transferred to E. coli BL21(DE3) expression host, and IPTG induced recombinant protein expression. The protein was purified using Ni-NTA column affinity chromatography, and the Western blotting method was utilized to confirm it. Finally, mice were immunized with three routes of purified protein. Statistical analysis of the control group injection and test results was carried out by t-test from SPSS software. Result(s): The optimized gene had a Codon adaptation index (CAI) of 0/97 Percentage of codons having high-frequency distribution was improved to 85%. Expression of recombinant protein in E.coli led to the production of BoNT/B-HCC with a molecular weight of 45 kDa. The total yield of purified protein was 43 mg/L. Immunization of mice induced serum antibody response. Statistical analysis showed that the antibody titer ratio was significantly different compared to the control sample and the antibody titer was acceptable up to a dilution of 1.256000 Conclusion(s): According to the present study results, the protein can be used as an immunogenic candidate for developing vaccines against SARS-CoV2 in future research.Copyright © 2022, Semnan University of Medical Sciences. All rights reserved.
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Introduction: Covid-19 epidemic results from an infection caused by SARS-CoV2. Evolution-based analyses on the nucleotide sequences show that SARS-CoV2 is a member of the genus Beta-coronaviruses and its genome consists of a single-stranded RNA, encoding 16 proteins. Among the structural proteins, the nucleocapsid is the most abundant protein in virus structure, highly immunogenic, with sequence conservatory. Due to a large number of mutations in the spike protein, the aim of this study was to investigate bioinformatics, expression of nucleocapsid protein and evaluate its immunogenicity as an immunogenic candidate Material(s) and Method(s): B and T cell epitopes of nucleocapsid protein were examined in the IEDB database. The PET28a-N plasmid was transferred to E. coli BL21(DE3) expression host, and IPTG induced recombinant protein expression. The protein was purified using Ni-NTA column affinity chromatography, and the Western blotting method was utilized to confirm it. Finally, mice were immunized with three routes of purified protein. Statistical analysis of the control group injection and test results was carried out by t-test from SPSS software. Result(s): The optimized gene had a Codon adaptation index (CAI) of 0/97 Percentage of codons having high-frequency distribution was improved to 85%. Expression of recombinant protein in E.coli led to the production of BoNT/B-HCC with a molecular weight of 45 kDa. The total yield of purified protein was 43 mg/L. Immunization of mice induced serum antibody response. Statistical analysis showed that the antibody titer ratio was significantly different compared to the control sample and the antibody titer was acceptable up to a dilution of 1.256000 Conclusion(s): According to the present study results, the protein can be used as an immunogenic candidate for developing vaccines against SARS-CoV2 in future research.Copyright © 2022, Semnan University of Medical Sciences. All rights reserved.
ABSTRACT
Melioidosis is a particularly dangerous infection with endemic distribution caused by the Gram-negative microorganism from the pathogenicity group II Burkholderia pseudomallei. In endemic countries, melioidosis holds one of the leading places in mortality rate after HIV, tuberculosis and, in recent years, COVID-19. The natural ecological pathogen niches are located in tropical and subtropical climate zones, primarily in Southeast Asia and Australia, where its existence as a species is maintained in moist soil and water in a certain temperature environmental range. However, at present, more and more often cases of melioidosis are registered outside endemic territories, which emphasizes the relevance of improving the means and methods of laboratory diagnostics of this disease both for countries located in the zone of natural foci as well as for local healthcare of the countries after importation of this poorly known infection into their territory. In such countries, including the Russian Federation, the population has no natural immunity to the pathogen, and therefore this infection acquires even greater clinical and epidemiological significance. In the Volgograd Plague Control Research Institute, an erythrocyte antigenic melioidosis diagnostic agent for IHA was designed allowing to detect the presence of serum melioidosis antibodies. The diagnostic agent was obtained on the basis of a biological carrier - ram erythrocytes sensitized with isolated protein antigenic complexes of B. pseudomallei. The high analytical characteristics of the diagnostic agent were confirmed on sera models of immunized and recovering experimental animals. Using the obtained set of reagents, the level of serum antibodies against the causative agent of melioidosis was studied in residents from the 3 provinces of Vietnam (Ha Giang, Lang Son and Quang Ninh), as well as in control group composed of residents of the Volgograd region. In samples obtained from a non-endemic region, not more than 25% of cases contained IHA titers at lower than 1:10 dilution, which is apparently due to cross-reactivity of serum immunoglobulins. Positive serum samples from clinically healthy residents of Ha Giang, Lang Son and Quang Ninh provinces were at a titer of 1:10 detected in 71.5%, in dilutions of 1:20-1:80 - in 28.5% of cases. Thus, we believe that serum antibody titer of 1:80 established in the IHA results, has a diagnostic significance, reflecting the intensity of the anti-melioidosis populational immunity.
ABSTRACT
Background: To mitigate the COVID-19 pandemic, many countries have recommended the use of booster vaccinations. The relationship between the degree of adverse vaccine reactions and elevated antibody titers is of interest;however, no studies have investigated the temporal changes in antibody titers based on repeated measurements after a third dose of the BNT162b2 vaccine. Methods: This prospective longitudinal cohort study was conducted with 62 healthcare workers who received a third dose of the BNT162b2 at Okayama University Hospital, Japan. Venous blood draw and fingertip whole blood test sample collection were conducted at the early (3–13 days) and 1-month time points;only FWT sample collection was conducted at the 2-month time point. Information on adverse reactions within 1 week after vaccination was also obtained. The association between fever of 37.5 °C or higher and antibody titers after the third dose of BNT162b2 was examined using a mixed-effects model and Poisson regression with robust variance. Results: A trend toward higher antibody titers in the early period after vaccination was observed in the febrile individuals, but the differences were not significant at 1 and 2 months post-vaccination (the partial regression coefficient for fever was 8094.3 [-1910.2, 18,098.8] at 1 month after vaccination, and 1764.1 [-4133.9, 7662.1] at 2 months after vaccination in the adjusted models). Conclusion: The findings suggest that the presence of fever after the third vaccine does not predict a sustained elevation in serum antibody titers. © 2022 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases
ABSTRACT
Melioidosis is a particularly dangerous infection with endemic distribution caused by the Gram-negative microorganism from the pathogenicity group II Burkholderia pseudomallei. In endemic countries, melioidosis holds one of the leading places in mortality rate after HIV, tuberculosis and, in recent years, COVID-19. The natural ecological pathogen niches are located in tropical and subtropical climate zones, primarily in Southeast Asia and Australia, where its existence as a species is maintained in moist soil and water in a certain temperature environmental range. However, at present, more and more often cases of melioidosis are registered outside endemic territories, which emphasizes the relevance of improving the means and methods of laboratory diagnostics of this disease both for countries located in the zone of natural foci as well as for local healthcare of the countries after importation of this poorly known infection into their territory. In such countries, including the Russian Federation, the population has no natural immunity to the pathogen, and therefore this infection acquires even greater clinical and epidemiological significance. In the Volgograd Plague Control Research Institute, an erythrocyte antigenic melioidosis diagnostic agent for IHA was designed allowing to detect the presence of serum melioidosis antibodies. The diagnostic agent was obtained on the basis of a biological carrier - ram erythrocytes sensitized with isolated protein antigenic complexes of B. pseudomallei. The high analytical characteristics of the diagnostic agent were confirmed on sera models of immunized and recovering experimental animals. Using the obtained set of reagents, the level of serum antibodies against the causative agent of melioidosis was studied in residents from the 3 provinces of Vietnam (Ha Giang, Lang Son and Quang Ninh), as well as in control group composed of residents of the Volgograd region. In samples obtained from a non-endemic region, not more than 25% of cases contained IHA titers at lower than 1:10 dilution, which is apparently due to cross-reactivity of serum immunoglobulins. Positive serum samples from clinically healthy residents of Ha Giang, Lang Son and Quang Ninh provinces were at a titer of 1:10 detected in 71.5%, in dilutions of 1:20-1:80 - in 28.5% of cases. Thus, we believe that serum antibody titer of 1:80 established in the IHA results, has a diagnostic significance, reflecting the intensity of the anti-melioidosis populational immunity. Copyright © 2022 Saint Petersburg Pasteur Institute. All rights reserved.