[Research progress of influenza vaccination, pneumococcal vaccination and COVID-19 vaccination among cancer patients].

This article reviews the relevant studies on the efficacy and safety of influenza, pneumococcal and COVID-19 vaccination among tumor patients worldwide in recent years. By combing and analyzing the retrieved literature, the results show that influenza and pneumococcal vaccination can significantly reduce the morbidity and hospitalization rate of infectious diseases in tumor patients, reduce the risk of cardiovascular events and death, and significantly improve survival prognosis. COVID-19 vaccination can also protect tumor patients, especially those who have completed full dose vaccination. Authoritative guidelines and consensuses worldwide all recommend that tumor patients receive influenza, pneumococcal and COVID-19 vaccines. We should carry out relevant researches, as well as take effective measures to strengthen patient education, so that tumor patients can fully experience the health protection brought by the vaccine to this specific group.

Application of convalescent plasma from patients with COVID-19 treatment of Coronavirus Disease 2019

The pandemic of Coronavirus Disease 2019 (COVID-19) in 2020 has posed a great challenge to global public health resources. Since there are no specific antiviral drugs at present, convalescent plasma (CP) from patients who have recovered from COVID-19 is one of the specific biologic therapies being considered to treat severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Preliminary studies have shown that the CP containing high titer neutralizing antibody against SARS-CoV-2 is safe and promising in blocking viral replication and improving patients'clinical symptoms. In this article, we briefly summarize the application of CP in treatment of COVID-19, and explores possible action mechanism, relevant clinical research and possible influencing factors of clinical effect, which may be helpful to the rational application of CP in treatment of COVID-19. Copyright © 2021 Changchun Institute of Biological Products. All rights reserved.

Specificity of 2019-nCoV nucleic acid detection kit (fluorescence PCR)

Objective To evaluate the specificity of three consecutive batches of 2019-nCoV nucleic acid detection kit (fluorescence PCR) manufactured by Shanghai GeneoDx Biotech Co., LTD. Methods A total of 55 common respiratory pathogens, including endemic human coronaviruses (HKU1, OC43, NL63 and 229E), severe acute respiratory syndrome conronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS), seasonal influenza virus, rhinovirus, adenovirus, Klebsiella pneumonia and Mycobacterium tuberculosis, were grouped and used for verification of cross reactivity of the detection kit. According to the requirements in the Key Points of Technical Review for Registration of 2019 New Coronavirus Nucleic Acid Detection Reagents issued by Center for Medical Device Evaluation, National Medical Products Administration (NMPA), human mucoprotein, human blood, phenylephrine, oxymetazoline, sodium chloride (including those as preservatives) and other 29 interfering substances were selected to verify the anti-interference substances of this kit. Results In the verification for cross reactivity, the test results of mixed positive samples by the three consecutive batches of kit were positive, while those of negative samples were negative, indicating a coincidence rate of accuracy of 100%. The cross-reactive substances showed no effect on the test result by the kit. All the test results of positive and borderline positive samples were positive, while those of negative samples were negative, indicating a coincidence rate of accuracy of 100%. All the 29 kinds of endogenous / exogenous interfering substances showed no influence on the test results by this kit. Conclusion Hie new coronavirus 2019-nCoV nucleic acid detection kit (fluorescence PCR method) manufactured by Shanghai GeneoDx Biotech Co., LTD. showed no cross-reactivity with 55 common respiratory pathogens, while showed anti-interference properties against endogenous and exogenous interfering substances such as host tissue, common respiratory pathogen and common drugs for respiratory diseases in clinic. The specificity test result of the kit met the requirements for registration of 2019 new coronavirus nucleic acid detection reagents. The test results of three consecutive batches of kits were highly stable. Copyright © 2021 Changchun Institute of Biological Products. All rights reserved.

Progress in research on recombinant vector vaccine against SARS-CoV-2

The global epidemic of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) poses a great threat to human life and health. At present, various types of vaccines have been approved for use worldwide to prevent the spread of the epidemic, among which recombinant vector vaccine plays an important role. Up to May 25, 2021, four vector vaccines have been approved for use in different countries, while 17 ones are in clinical trials and more than 40 ones in preclinical studies. This paper summarizes the research status of recombinant vector vaccine against SARS-CoV-2 in the world.

Collection and quality characteristics of Coronavirus Disease 2019 convalescent plasma

Objective To explore the application and safety of apheresis technology in collection of Coronavirus Disease 2019 (COVID-19) convalescent plasma (CP), and to analyze the quality characteristics of the plasma. Methods The general data of COVID-19 convalescent plasma (CP) donors, including gender, age, date of discharge or release from medical isolation, were collected based on informed consent. After physical examination, the CP was collected by apheresis technology with plasma separator, inactivated with methylene blue, and determined for severe acute respiratory symptom Coronavirus 2 (SARS-CoV-2) nucleic acid and specific antibody (RBD-IgG) against SARS-CoV-2. Results The collection process went well, and no serious adverse events related to plasma collection were reported during or after the collection. The average age of COVID-19 CP donors was 38 years (n = 933). The distributions of blood groups A, B, AB and 0 in RhD (+) COVID-19 CP were 33. 4%, 29. 2%, 10% and 27. 2% respectively. The plasma donation date was 18 d from the discharge date in average. All the test results of SARS-CoV-2 nucleic acid in CP were negative, while the proportion of plasma samples at SARS-CoV-2 antibody titer of more than 1: 160 was 92. 60%. Conclusion Apheresis technology was safe and reliable. The COVID-19 CP contained high titer antibody. Large-scale collection and preparation of inactivated plasma against SARS-CoV-2 played an important role in the treatment of COVID-19.

Application of convalescent plasma from patients with COVID-19 treatment of Coronavirus Disease 2019

The pandemic of Coronavirus Disease 2019 (COVID-19) in 2020 has posed a great challenge to global public health resources. Since there are no specific antiviral drugs at present, convalescent plasma (CP) from patients who have recovered from COVID-19 is one of the specific biologic therapies being considered to treat severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Preliminary studies have shown that the CP containing high titer neu¬tralizing antibody against SARS-CoV-2 is safe and promising in blocking viral replication and improving patients'clinical symptoms. In this article, we briefly summarize the application of CP in treatment of COVID-19, and explores possible action mechanism, relevant clinical research and possible influencing factors of clinical effect, which may be helpful to the rational application of CP in treatment of COVID-19.

Specificity of 2019-nCoV nucleic acid detection kit (fluorescence PCR)

Objective To evaluate the specificity of three consecutive batches of 2019-nCoV nucleic acid detection kit (fluorescence PCR) manufactured by Shanghai GeneoDx Biotech Co., LTD. Methods A total of 55 common respiratory pathogens, including endemic human coronaviruses (HKU1, OC43, NL63 and 229E), severe acute respiratory syndrome conronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS), seasonal influenza virus, rhinovirus, adenovirus, Klebsiella pneumonia and Mycobacterium tuberculosis, were grouped and used for verification of cross reactivity of the detection kit. According to the requirements in the Key Points of Technical Review for Registration of 2019 New Coronavirus Nucleic Acid Detection Reagents issued by Center for Medical Device Evaluation, National Medical Products Administration (NMPA), human mucoprotein, human blood, phenylephrine, oxymetazoline, sodium chloride (including those as preservatives) and other 29 interfering substances were selected to verify the anti-interference substances of this kit. Results In the verification for cross reactivity, the test results of mixed positive samples by the three consecutive batches of kit were positive, while those of negative samples were negative, indicating a coincidence rate of accuracy of 100%. The cross-reactive substances showed no effect on the test result by the kit. All the test results of positive and borderline positive samples were positive, while those of negative samples were negative, indicating a coincidence rate of accuracy of 100%. All the 29 kinds of endogenous / exogenous interfering substances showed no influence on the test results by this kit. Conclusion Hie new coronavirus 2019-nCoV nucleic acid detection kit (fluo¬rescence PCR method) manufactured by Shanghai GeneoDx Biotech Co., LTD. showed no cross-reactivity with 55 common respiratory pathogens, while showed anti-interference properties against endogenous and exogenous interfering substances such as host tissue, common respiratory pathogen and common drugs for respiratory diseases in clinic. The specificity test result of the kit met the requirements for registration of 2019 new coronavirus nucleic acid detection reagents. The test results of three consecutive batches of kits were highly stable.

Development strategies and research progress of SARS CoV 2 neutralizing antibody

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has evolved into a pandemic, which has imposed a burden on the global economy and public health, thus effective response measures are urgently needed. Antibodies have a good historic documented in the prevention and treatment of emerging infectious diseases. At present, hundreds of development projects for SARS-CoV-2 neutralizing antibodies around the world are ongoing by using different strategies, with some in clinical trials. This article reviews the current development strategies and research progress of SARS-CoV-2 neutralizing antibodies in the fields of target selection, antibody screening techinqne, functional evaluation and possible challenges.

Research and development progress of SARS-CoV-2 neutralizing antibody

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has widely spread around the world, exerting great impacts on economic growth and human life. It is the highest priority to develop safe and effective drugs. Neutralizing antibodies have achieved good results in previous clinical applications of some viral infectious diseases. They can be used not only for the short-term prevention of SARS-COV-2 infection, but also for the treatment of corona virus disease 2019 (COVID-19), showing important application value. At present, the research and development of SARS-CoV-2 neutralizing antibody has made its rapid progress in China and abroad. Many antibody drugs have entered clinical trials and been put into emergency use. This article mainly summarizes targets of SARS-CoV-2 neutralizing antibody, screening technologies, drug development progresses and problems to be concerned.

Analysis and evaluation of 670 convalescent plasma samples from patients with COVID-19 infection

Objective: To systematically analyze the 670 convalescent plasma (CP) samples from patients with coro-navirus disease 2019 (COVID-19). Methods: The plasma samples were analyzed and evaluated for routine test items including hepatitis B virus surface antigen (HBsAg), hepatitis C virus (HCV) antibody, human immunodeficiency virus (HIV)-l/HI V-2 antibody, Treponema pallidum (TP) and alanine aminotransferase (ALT) as well as blood group, nucleic acid of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), IgG antibody, methylene blue residue and sterility. Results: A total of 121 substandard plasma samples were detected from 670 convalescent plasma samples, of which substandard IgG antibody titer accounted for the highest proportion of 7. 91%. In the turn of proportions, the blood groups were A (32. 52%), B (29. 94%), 0 (28. 886%) and AB (8. 66%). Ml the test results of nucleic acids of SARS-CoV-2 were negative. A total of 485 samples were from Wuhan, of which the highest proportion (21. 95%) were from the donors at ages of > 30 ∼ 35 years, including 264 males and 221 females. Of the high titer plasma, those at titers of not less than 1: 640 accounted for the highest proportion (77. 43%). Most of the IgG titers in plasma of common patients were not less than 1: 640 > 10 - 20 d, while were less than 1: 160 3 ∼ 10 d, after hospitalization. However, 35 plasma samples were negative for IgG antibody (at titers of less than 1: 80), in 9 of which other pathogens were detected. Conclusion: Unqualified IgG titer was the main reason for unqualified CP. The proportion of CP of group O was lower than that of the group in healthy population. The highest proportion of plasma donors in Wuhan was in the populations at ages of > 30 ∼ 35 years, which was higher in males than in females. Satisfactory immune responses were induced in most of patients in convalescence period, which removed the virus in vivo effectively. High antibody titers were induced > 10 ~ 20 d after hospitalization, making the common cases were not easy to change into severe ones. It was speculated that patients negative for IgG antibody might be infected with other pathogens. © 2020 Changchun Institute of Biological Products. All rights reserved.

[Evaluation of safety of two inactivated COVID-19 vaccines in a large-scale emergency use].

Objective: To evaluate the safety of two inactivated COVID-19 vaccines in a large-scale emergency use. Methods: Based on the "Vaccination Information Collection System", the incidence data of adverse reactions in the population vaccinated with the inactivated COVID-19 vaccines developed by Beijing Institute of Biological Products Co., Ltd and Wuhan Institute of Biological Products Co., Ltd, respectively, in emergency use were collected, and the relevant information were analyzed with descriptive epidemiological and statistical methods. Results: By December 1, 2020, the vaccination information of 519 543 individuals had been collected. The overall incidence rate of adverse reactions was 1.06%, the incidence rate of systemic adverse reactions was 0.69% and the incidence rate of local adverse reactions was 0.37%. The main systemic adverse reactions included fatigue, headache, fever, cough and loss of appetite with the incidence rates of 0.21%, 0.14%, 0.06%, 0.05% and 0.05%, respectively; the main local adverse reactions were injection site pain and injection site swelling with the incidence rates of 0.24% and 0.05%, respectively. Conclusion: The two inactivated COVID-19 vaccines by Beijing Institute of Biological Products Co., Ltd and Wuhan Institute of Biological Products Co., Ltd showed that in the large-scale emergency use, the incidence rate of general reactions was low and no serious adverse reactions were observed after the vaccinations, demonstrating that the vaccines have good safety.

Establishment and validation of competitive ELISA for detecting blocking activity of monoclonal antibody against SARS-CoV-2 RBD

Objective: To establish and verify a competitive ELISA method for the detection of blocking activity of monoclonal antibody against SARS-CoV-2 RBD, and to compare the results by correlation analysis with that of live virus neutralization activity measured by the plaque reduction neutralization test (PRNT). Methods: Using RBD-Fc as coating antigen, ACE2-His and anti-SARS-CoV-2 RBD monoclonal antibodies were added to competitively bind to RBD. Anti-6×his antibody labeled with horseradish peroxidase was used as the secondary antibody. The competitive ELISA method detecting the ability of McAb to block the binding of RBD to ACE2 was established. The specificity, relative accuracy, precision, linearity and range of the method were verified. Seven monoclonal antibodies against SARS-CoV-2 RBD were detected by this method. The results were compared with PRNT method, and correlation analysis was performed. Results: The blocking activity of the relevant anti-SARS-CoV-2 RBD monoclonal antibody on RBD and ACE2 protein can be effectively detected using the established competitive ELISA method. The blocking ability of McAb was dose-dependent and conformed to the four-parameter equation. The samples with theoretical titers of 64%, 80%, 100%, 125% and 156% were determined for 10 times, and the relative bias was within ±20%. The logarithm (abscissa) of theoretical potency value was used for linear regression to the logarithm (ordinate) of the corresponding titer determination value. The regression equation was y=1.156x-0.021 3, in which the slope was between 0.8 and 1.25, meaning good relative accuracy. The geometric coefficient of variation (GCV%) of the relative titers of each titer level were 2.6%, 5.2%, 3.6%, 3.4% and 10.2%, respectively, all of which were less than 20% with good precision. The correlation coefficient of linear regression equation was 0.985, meeting the requirements. The relative accuracy, intermediate precision and linearity of the method all met the requirements of the titer level range was 64%~156%. The detection results of the blocking activity of the 7 RBD monoclonal antibodies showed good correlation with the results of the live virus neutralization activity measured by the PRNT method. Conclusion: A competitive ELISA method for the detection of anti-SARS-CoV-2 RBD monoclonal antibody has been successfully established. The method has satisfied specificity, accuracy, precision and linearity. The results had a good correlation with that by PRNT method. It can be used to indirectly evaluate the neutralizing activity of related SARS-CoV-2 monoclonal antibodies against the live viruses.