ABSTRACT
【Objective】 To investigate the trend of neutralizing antibody level in plasma donors who received the 3rd shot of inactivated novel coronavirus vaccine. 【Methods】 Three commercial ELISA kits for novel coronavirus neutralization antibody detection, manufactured by Company A, B and C, were chosen and screened by Pseudotype Neutralization Test from December 2021 to June 2022. A total of 410 plasma samples from 64 plasma donors who received the 3rd shot of inactivated novel coronavirus vaccine and there after donated plasma within six months were detected by the selected ELISA kit from July to October, 2022. The data were analyzed by Excel 2013 and SPSS 26 software. 【Results】 The high-throughput ELISA kit for SARS-CoV-2 neutralizing antibody detection, manufactured by Company A, was selected for further antibody titer detection. The mixed plasma titers were 1 337.34, 1 148.89, 852.19, 681.38, 556.44 and 457.19 U/mL from 1 to 6 months, respectively, after the 3rd shot of vaccine. The neutralizing antibody titer level began to increase around 7 days after the 3rd shot of vaccine injection and peaked (peak range: 264.07-2 208.39 U/mL, median: 569.34 U/mL) at 1 month (range: 9-43 days, median: 22 days), and then gradually decreased (P<0.05). 【Conclusion】 The neutralizing antibody titer of plasma donors who received the 3rd shot of inactivated novel coronavirus vaccine began to rise around 7 days after vaccination, which reached the peak value at around 1 month and then gradually decreased.
ABSTRACT
【Objective】 To screen the sterilizing-grade filters applicable for production of human coagulation factor Ⅷ/von Willebrand factor complex(FⅧ/VWF)and study the sterilization filtration process. 【Methods】 Four sterilizing-grade filters for FⅧ/VWF were evaluated through indicators such as filtration capacity, filtration flux, recovery rate of FⅧ activity, recovery rate of VWF activity, recovery rate of VWF antigen, recovery rate of protein and VWF molecular distribution. The sterilizing-grade filter with the best filtration performance was selected for further study. The study was designed by general full-factor design to determine the appropriate filitered protein concentration and filitered speed range through evaluating the total filtered protein amount, recovery rate of protein and filtration efficiency, and then the process operation parameters was determined. 【Results】 The filtration flux of Sartobran P, Sartopore 2 XLG, Sartopore Platinum and Sartopore 2 XLI were 1.71±0.01, 1.80±0.01, 1.34±0.01, and 1.81±0.04 L·(m2)-1·min-1, respectively; the recovery rates (%) of FⅧ activity were 97.09±2.82, 99.22±0.99, 96.87±1.85 and 93.76±1.21, respectively; the recovery rates (%) of VWF activity were 98.12±1.42, 99.95±1.85, 94.80±1.62 and 92.09±1.67, respectively. Between Sartopore 2 XLG and Sartobran P, the difference of filtration flux (P<0.001) was statistically significant; between Sartopore 2 XLG and Sartopore Platinum, the differences of the filtration flux (P<0.001) and VWF potency recovery rate (P<0.05) were statistically significant; between Sartopore 2 XLG and Sartopore 2 XLI, the differences of FⅧ potency recovery rate (P<0.01) and VWF potency recovery rate (P<0.01) were statistically significant. The optimal process operating space of Sartopore 2 XLG was protein concentration of 0.45-0.58 mg/mL, and filtration rate of 1.48-2.95 L·(m2)-1·min-1. 【Conclusion】 Sartopore 2 XLG is the most suitable filter for the production of FⅧ/VWF and the DoE test proves that it has good process operation space.
ABSTRACT
Plasma protein products, essential drugs for various clinical diseases, are therapeutic biological products extracted from healthy human plasma. The research and development of new plasma protein products, led by United States and European, has been widely deepened and enhanced. Therefore, accelerating the development of new plasma protein products in China is of great significance. This review summarizes the research and development of plasma protein products that have been marketed abroad but have not produced in China, as well as analyzes the difficulties and prospects of the development of plasma protein products in China.
ABSTRACT
【Objective】 To establish a method for detecting human immunoglobulin Fc function based on surface plasmon resonance technology. 【Methods】 Based on the characteristic that FcγRI can be binded to the Fc segment of IgG, the affinity constant of the sample was detected by surface plasmon resonance, and its Fc function was the KD ratio of the sample to the standard. The method was validated for specificity/specificity, precision and robustness. The method and the pharmacopoeia method were used to detect the Fc function of 30 human immunoglobulins, and the correlation and consistency of the detection results were analyzed. 【Results】 The method validation results showed that this method has strong specificity/specificity (t values were 0.15, 0.22, both P>0.05), good precision (CV value 5.37%~10.69%) and good robustness (CV value 10.06%). The detection results of this method and the pharmacopoeia method have high correlation (r=0.96, P<0.05) and high consistency (Bias-2.060, 95% Limits of Agreement-5.628~1.508). 【Conclusion】 A method for detecting human immunoglobulin Fc function based on surface plasmon resonance has been successfully established.
ABSTRACT
【Objective】 To study the effect of different concentrations of heparin, ATⅢ or a mixture of heparin and antithrombin Ⅲ (ATⅢ) (1∶1)on the activity of human coagulation factor Ⅸ (FⅨ). 【Methods】 The heparin or heparin/ATⅢ with different concentrations were added into human coagulation Ⅸ products or human prothrombin complex (PCC) to prepare heparin or heparin/ATⅢ samples, containing 0, 0.1, 0.3, 0.5, 0.8, 1, 2 and 4 IU per unit. ATⅢ with different concentrations were added into FⅨ or PCC to prepare ATⅢ samples containing ATⅢ 0, 0.1, 0.5 and 1 IU per unit. The FⅨ activity of the samples prepared was tested by one-stage coagulation method. Then corresponding amount of protamine sulfate were added to neutralize heparin or heparin/ATⅢ to detect the FⅨ activity again. Their influence of heparin, ATⅢ and heparin/ATⅢ with different concentrations on the activity of FⅨ were analyzed. 【Results】 When the content of heparin or heparin/ATⅢ was 0, 0.1, 0.3 and 0.5 IU per unit of FⅨ, the detection results of FⅨ titer in samples were consistent. When the content of heparin or heparin/ATⅢ per unit of FⅨ was 0.8, 1, 2 and 4 IU, the detection results of FⅨ titer were all lower than those of samples without heparin. When the ATⅢ content was 0, 0.1, 0.5 and 1 IU, the FⅨ titer of the samples was consistent. 【Conclution】 When the content of heparin or heparin/ATⅢ in the product is less than or equal to 0.5 IU per IU of FⅨ, the step of protamine sulfate adding could be omitted as it has little effect on FⅨ activity. When >0.5 IU per IU of FⅨ, however, protamine sulfate adding, to neutralize heparin, is necessary before FⅨ activity testing.