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Objective:To evaluate the immunogenicity of Madin-Darby canine kidney (MDCK) cell-based quadrivalent influenza split vaccine (MDCK-Va) combined with different adjuvants.Methods:Different doses of MDCK-Va and chicken embryo-based quadrivalent influenza split vaccine (egg-Va) were intramuscularly immunized BALB/c mice twice with an interval of three weeks. Serum samples were collected to detect antibody titers using hemagglutination inhibition (HI) assay. BALB/c mice were immunized with different doses of MDCK-Va combined with QS21, AddVax, PolyI∶C, CpG ODN 1826 and AddVax/PolyI∶C (Add/Poly), respectively. HI and microneutralization assays were used to detect antibody titers 21 d after the first and booster immunization. Spleen tissues were collected from the mice immunized with 10 μg MDCK-Va combined with the above adjuvants 5 d after the booster immunization to analyze spleen index and the types of spleen cells.Results:The immunoprotective effect of MDCK-Va was not inferior to that of egg-Va. MDCK-Va combined with each of the above adjuvants could induce higher HI antibody titer than MDCK-Va alone, especially the QS21/Va and Add/Poly/Va groups, and the differences were statistically significant. For H1N1 vaccine, the Pearson′s correlation coefficient ( r) between HI antibody and neutralizing antibody was 0.737-0.910, and for H3N2 subtype vaccine, the value of r was 0.839-0.947. Compared with the MDCK-Va group, the QS21/Va group showed significantly increased spleen index and decreased proportion of single lymphocytes. QS21 and Add/Poly were much better than other adjuvants in stimulating mouse splenic neutrophils and CD4/CD8 cells. Conclusions:Add/Poly had a stronger immune enhancement effect on MDCK-Va, suggesting that it was a potential adjuvant for MDCK-Va. The antibody titer detected by HI and MN assays had a strong positive correlation.
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Objective:To investigate the feasibility of dynamic turbidity method for the detection of bacterial endotoxin content in influenza split vaccine. Methods: According to the bacterial endotoxin detection method described in general rule 1143 in Chinese Pharmacopoeia (2015 edition), the reliability test for standard curves of influenza split vaccine, the interference initial screening test, the interference verification test and the endotoxin content were performed or determined, and the results were compared with those by the gel method for the same batches of vaccine. Results:The results of reliability test for standard curves were accordance with the reg-ulations. In the interference initial screening test, vaccine was diluted by 160 times, 320 times and 640 times, and the recovery was between 50% and 200%, which showed no interference. The results of the interference verification test further proved that vaccine with 640 times dilution had no interference effect on test. The bacterial endotoxin contents of 10 batches of influenza split vaccine deter-mined by the turbidity method were less than the limit value of 20 EU·ml-1 , and the results were the same as those determined by the gel method. Conclusion:It is feasible to detect the content of bacterial endotoxin in influenza split vaccine by the dynamic turbidity method, which is worthy of promoted application.
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PURPOSE: A phase I clinical trial was conducted to evaluate the immunogenicity and safety of newly developed egg-cultivated trivalent inactivated split influenza vaccine (TIV) in Korea. MATERIALS AND METHODS: The TIV was administered to 43 healthy male adults. Subjects with high pre-existing titers were excluded in a screening step. Immune response was measured by a hemagglutination inhibition (HI) assay. RESULTS: The seroprotection rates against A/California/7/2009 (H1N1), A/Perth/16/2009 (H3N2) and B/Brisbane/60/2009 were 74.42% [95% confidence interval (CI): 61.38–87.46], 72.09% (95% CI: 58.69–85.50), and 86.05% (95% CI: 75.69–96.40), respectively. Calculated seroconversion rates were 74.42% (95% CI: 61.38–87.46), 74.42% (95% CI: 61.38–87.46), and 79.07% (95% CI: 66.91–91.23), respectively. There were 25 episodes of solicited local adverse events in 21 subjects (47.73%), 21 episodes of solicited general adverse events in 16 subjects (36.36%) and 5 episodes of unsolicited adverse events in 5 subjects (11.36%). All adverse events were grade 1 or 2 and disappeared within three days. CONCLUSION: The immunogenicity and safety of TIV established in this phase I trial are sufficient to plan a larger scale clinical trial.
Subject(s)
Adult , Humans , Male , Hemagglutination , Influenza Vaccines , Influenza, Human , Korea , Mass Screening , SeroconversionABSTRACT
Objective To evaluate the irnmunogenicity, safety and stability of the manufacture process regarding three consecutive lots of influenza split vaccines (Anflu ). Methods A double-blind, randomized and controlled clinical trial was conducted in healthy volunteers. A total of 566 subjects aged 18 to 60 years were recruited and stratified into four age groups before randomly assigned into four groups. Each group would receive one dose of influenza vaccine from either one of the three lots ofAnflu or one lot of the licensed control vaccine. Each dose of the vaccines contained 15 μg of each of the H1N1, H3N2 and B type antigen. Safety was assessed through 30-minute observation for immediate allergic reaction and three-day observation after vaccination. HI antibody titers were determined before vaccination and on day 21, after vaccination. Results Mild adverse reaction was reported and the overall incidence rates on fever of the four groups were from 1.4% to 2.8% but no significant difference was observed between groups. Seroconversion rates of the three viral strains in four groups were 80.3% and above with fold increase as≥11.1 and protection rate was≥93.4%. For the three lots of investigated vaccines, all of the indexes of the three viral strains in four groups exceeded the standards on EMEA and FDA for influenza vaccine. Conclusion The three consecutive lots of Anflu appeared to be good, with both consistent immunogenieity and safety, indicating the stability of manufacture process.