Aim To explore the feasibility of the micro- dynamic chromogenic method for quantitative detection of bacterial endotoxin in recombinant novel coronavirus vaccine ( CHO cell).Methods The micro-dynamic color method of Limulus reagent was used to establish a bacterial endotoxin standard curve.The dilution factor was determined through interference pre -experiment, the recoverv rate of the endotoxin added to the test so- J lution was determined, and the interference test to complete the quantitative detection test of the bacterial endotoxin content in the test product was performed, and the results were compared with those of the gel-clot method.Results Hie linear range of the concentration of the standard curve was 0.02 to 2.0 EU • mL 1 , and the regression equation of the standard curve was lgT =-0.302 7 lgC +2.858 7( r = 0.998 9).When recombinant novel coronavirus vaccine ( CHO cell) was cliluted 40 times or below, the micro -dynamic chromogenic reagent did not interfere with the bacterial endotoxin agglutination reaction, and the recovery rate was 50% to 200%.The test results were consistent with the gel- clot method.Conclusions The micro-dynamic chromogenic method can be used for the quantitative detection of bacterial endotoxins in recombinant novel coronavirus vaccine ( CHO cell) with accurate results, high sensitivity, and process monitoring.

Objective:To prepare 68Ga-2-(4, 7-bis(carboxymethyl)-1, 4, 7-triazonan-1-yl)pentanedioic acid (NODAGA)-YHWYGYTPQNVI (GE11) and evaluate its feasibility of PET imaging for pancreatic cancer. Methods:GE11 peptide was conjugated with NODAGA and then labeled with 68Ga. The labeling yield, radiochemical purity, hydrophilicity, stability and specificity in vitro were determined. Human pancreatic cancer BxPC3 nude mice models ( n=9) were established. MicroPET imaging was then obtained after 30 and 90 min, and mice were sacrificed at 90 min to acquire the radioactivity distribution of main organs and tumors. Pair t test was used to analyze the data. Results:The labeling yield was (73.5±5.4)% and radiochemical purity was more than 98%. After incubation 120 min in mouse serum at 37 ℃, radiochemical purity was more than 92%. The uptake was specific in BxPC3 cell lines. MicroPET images showed that 68Ga-NODAGA-GE11 could accumulate quickly in tumor. Value of tumor uptake was significantly higher than that of normal pancreas at 90 min ((1.38±0.25) vs (0.49±0.07) %ID/g; t=12.67, P<0.05), and the radio-uptake of blood, muscle and bone was lower than that of tumor. Conclusions:68Ga-NODAGA-GE11 is easy to be prepared with high radiochemical purity and good stability, and can specifically target BxPC3 xenograft tumor. However, due to the high uptake in the kidneys and liver, the value of 68Ga-NODAGA-GE11 in PET imaging for pancreatic tumor needs further study.

Objective: To evaluate the immunogenicity, safety, and immune persistence of the sequential booster with the recombinant protein-based COVID-19 vaccine (CHO cell) in healthy people aged 18-84 years. Methods: An open-label, multi-center trial was conducted in October 2021. The eligible healthy individuals, aged 18-84 years who had completed primary immunization with the inactivated COVID-19 vaccine 3 to 9 months before, were recruited from Shangyu district of Shaoxing and Kaihua county of Quzhou, Zhejiang province. All participants were divided into three groups based on the differences in prime-boost intervals: Group A (3-4 months), Group B (5-6 months) and Group C (7-9 months), with 320 persons per group. All participants received the recombinant COVID-19 vaccine (CHO cell). Blood samples were collected before the vaccination and after receiving the booster at 14 days, 30 days, and 180 days for analysis of GMTs, antibody positivity rates, and seroconversion rates. All adverse events were collected within one month and serious adverse events were collected within six months. The incidences of adverse reactions were analyzed after the booster. Results: The age of 960 participants was (52.3±11.5) years old, and 47.4% were males (455). The GMTs of Groups B and C were 65.26 (54.51-78.12) and 60.97 (50.61-73.45) at 14 days after the booster, both higher than Group A's 44.79 (36.94-54.30) (P value<0.05). The GMTs of Groups B and C were 23.95 (20.18-28.42) and 27.98 (23.45-33.39) at 30 days after the booster, both higher than Group A's 15.71 (13.24-18.63) (P value <0.05). At 14 days after the booster, the antibody positivity rates in Groups A, B, and C were 91.69% (276/301), 94.38% (302/320), and 93.95% (295/314), respectively. The seroconversion rates in the three groups were 90.37% (272/301), 93.75% (300/320), and 93.31% (293/314), respectively. There was no significant difference among these rates in the three groups (all P values >0.05). At 30 days after the booster, antibody positivity rates in Groups A, B, and C were 79.60% (238/299), 87.74% (279/318), and 90.48% (285/315), respectively. The seroconversion rates in the three groups were 76.92% (230/299), 85.85% (273/318), and 88.25% (278/315), respectively. There was a significant difference among these rates in the three groups (all P values <0.001). During the sequential booster immunization, the incidence of adverse events in 960 participants was 15.31% (147/960), with rates of about 14.38% (46/320), 17.50% (56/320), and 14.06% (45/320) in Groups A, B, and C, respectively. The incidence of adverse reactions was 8.02% (77/960), with rates of about 7.50% (24/320), 6.88% (22/320), and 9.69% (31/320) in Groups A, B, and C, respectively. No serious adverse events related to the booster were reported. Conclusion: Healthy individuals aged 18-84 years, who had completed primary immunization with the inactivated COVID-19 vaccine 3 to 9 months before, have good immunogenicity and safety profiles following the sequential booster with the recombinant COVID-19 vaccine (CHO cell).
Male ; Cricetinae ; Animals ; Humans ; Adult ; Middle Aged ; Female ; COVID-19 Vaccines ; Immunization, Secondary ; CHO Cells ; COVID-19/prevention & control* ; Recombinant Proteins ; Antibodies, Viral ; Antibodies, Neutralizing

Objective: To evaluate the immunogenicity, safety, and immune persistence of the sequential booster with the recombinant protein-based COVID-19 vaccine (CHO cell) in healthy people aged 18-84 years. Methods: An open-label, multi-center trial was conducted in October 2021. The eligible healthy individuals, aged 18-84 years who had completed primary immunization with the inactivated COVID-19 vaccine 3 to 9 months before, were recruited from Shangyu district of Shaoxing and Kaihua county of Quzhou, Zhejiang province. All participants were divided into three groups based on the differences in prime-boost intervals: Group A (3-4 months), Group B (5-6 months) and Group C (7-9 months), with 320 persons per group. All participants received the recombinant COVID-19 vaccine (CHO cell). Blood samples were collected before the vaccination and after receiving the booster at 14 days, 30 days, and 180 days for analysis of GMTs, antibody positivity rates, and seroconversion rates. All adverse events were collected within one month and serious adverse events were collected within six months. The incidences of adverse reactions were analyzed after the booster. Results: The age of 960 participants was (52.3±11.5) years old, and 47.4% were males (455). The GMTs of Groups B and C were 65.26 (54.51-78.12) and 60.97 (50.61-73.45) at 14 days after the booster, both higher than Group A's 44.79 (36.94-54.30) (P value<0.05). The GMTs of Groups B and C were 23.95 (20.18-28.42) and 27.98 (23.45-33.39) at 30 days after the booster, both higher than Group A's 15.71 (13.24-18.63) (P value <0.05). At 14 days after the booster, the antibody positivity rates in Groups A, B, and C were 91.69% (276/301), 94.38% (302/320), and 93.95% (295/314), respectively. The seroconversion rates in the three groups were 90.37% (272/301), 93.75% (300/320), and 93.31% (293/314), respectively. There was no significant difference among these rates in the three groups (all P values >0.05). At 30 days after the booster, antibody positivity rates in Groups A, B, and C were 79.60% (238/299), 87.74% (279/318), and 90.48% (285/315), respectively. The seroconversion rates in the three groups were 76.92% (230/299), 85.85% (273/318), and 88.25% (278/315), respectively. There was a significant difference among these rates in the three groups (all P values <0.001). During the sequential booster immunization, the incidence of adverse events in 960 participants was 15.31% (147/960), with rates of about 14.38% (46/320), 17.50% (56/320), and 14.06% (45/320) in Groups A, B, and C, respectively. The incidence of adverse reactions was 8.02% (77/960), with rates of about 7.50% (24/320), 6.88% (22/320), and 9.69% (31/320) in Groups A, B, and C, respectively. No serious adverse events related to the booster were reported. Conclusion: Healthy individuals aged 18-84 years, who had completed primary immunization with the inactivated COVID-19 vaccine 3 to 9 months before, have good immunogenicity and safety profiles following the sequential booster with the recombinant COVID-19 vaccine (CHO cell).
Male ; Cricetinae ; Animals ; Humans ; Adult ; Middle Aged ; Female ; COVID-19 Vaccines ; Immunization, Secondary ; CHO Cells ; COVID-19/prevention & control* ; Recombinant Proteins ; Antibodies, Viral ; Antibodies, Neutralizing

Objective: To establish a real-time fluorescence recombinase acid amplification (RAA) method for the detection of adenovirus type 3(HAdV-3)without extraction nucleic acid. Methods: According to the conserved sequence of adenovirus type 3 gene, a pair of primers and a probe were designed, and a real-time fluorescence RAA without extracting nucleic acid was established and optimizing the condition of DNA-free extraction. The sensitivity of the method was analyzed by a series of dilution and the specificity of the method was evaluated by detecting the original samples of other respiratory viruses. The clinical samples of HAdV-3 were detected and compared with the traditional real-time fluorescence quantitative PCR method for nucleic acid extraction. Results: The sensitivity of the real-time fluorescence RAA method was as high as that of qPCR in the detection of 10 series diluted HAdV-3 strains. The highest corresponding CT value of qPCR was 36.87. The sensitivity of the real-time fluorescence RAA method was similar to that of the real-time fluorescence quantitative PCR method . There was no cross-reaction to other common types of respiratory viruses. The two method were used to detect 56 clinical samples at the same time, and the result were completely consistent. Conclusions We provide the first report of the real-time fluorescent RAA assays for the detection of HAdV-3 without extracting nucleic acid and it has high sensitivity and specificity. Is suitable for rapid detection of HAdV-3 in clinical laboratories and on-site unite.