Discussion on the factors influencing the curative effect of Tuina (Chinese massage) / 国际中医中药杂志

Tuina (Chinese massage) is an important part of Traditional Chinese Medicine. It is a simple and inexpensive technique, and has shown effectiveness for muscle and bone diseases, visceral diseases, gynecological diseases, and common diseases in children. This paper aims to analyze the factors influencing the effects of Tuina. The factors included the aspects of diagnosis, treatment, prognosis, patient factors and doctor-patient communication. During the treatment of Tuina, doctors should carry out good doctor-patient communication, properly evaluate and exam patients, and clarify diagnosis, take appropriate Tuina techniques according to the patients' constitution, health condition, and comorbidity. Only in such way, could Tuina achieve effectiveness and safety.

Immunogenicity of quadrivalent influenza virus subunit vaccine combined with RFH01 adjuvant in mice / 中华微生物学和免疫学杂志

Objective:To evaluate the immunogenicity of a quadrivalent subunit vaccine combined with RFH01 adjuvant in a mouse model.Methods:Identification tests were performed on four monovalent influenza virus subunit vaccine stock solutions according to the methods described in Part 3 of the Chinese Pharmacopoeia 2020 Edition. In the study of the quadrivalent subunit vaccine combined with RFH01 adjuvant, 460 female BALB/c mice (6-8 weeks old) were randomly divided into 46 groups including experimental groups, vaccine control group, negative control group and blank group with 10 mice in each group. In the study of the quadrivalent subunit vaccine in old and young mice, 80 female 10-month-old and 80 female 10-week-old BALB/c mice were randomly divided into 16 groups ( n=10) including monovalent influenza virus vaccine group, quadrivalent subunit vaccine group, quadrivalent subunit vaccine+ RFH01 adjuvant group, chicken embryo quadrivalent split vaccine control group and PBS group. All mice were immunized by intramuscular injection. At 21 d after the primary immunization, a booster immunization was conducted using the same strategy. Blood samples were collected at 21 d and 42 d after the primary immunization for serum separation. Haemagglutination inhibition (HI) test was performed to detect the antibody levels in mouse serum samples. Results:After the booster immunization, the positive conversion rates in all vaccine+ RFH01 adjuvant groups reached 100%, and the geometric mean titers (GMTs) of serum antibodies were significantly higher than those of the vaccine groups without RFH01 adjuvant. There were significant differences in serum antibody titers between the monovalent/quadrivalent subunit vaccine groups with and without RFH01 adjuvant. After the booster immunization, the titers of serum antibodies against H1N1, H3N2, B/Victoria and B/Yamagata in the 10-week-old mice were significantly higher than those in the 10-month-old mice.Conclusions:The monovalent and quadrivalent influenza virus vaccines in combination with RFH01 adjuvant could elicit higher antibody titers in young (6-10 weeks old) and old (10 months old) mice, showing good immunogenicity.

Purification of H5N1 influenza virus by different chromatography media / 中华微生物学和免疫学杂志

Objective:To purify H5N1 influenza virus concentrate prepared by MDCK cells with a new mixed-mode chromatography medium Capto Core700 and the traditional medium Sepharose 4FF, and to compare the separation and purification efficacy of the two media.Methods:Capto Core700 and Sepharose 4FF were used to purify inactivated H5N1 influenza virus concentrate. The morphology of virus particles in different samples was then observed under a transmission electron microscope. Single radial immunodiffusion (SRID), Folin-Phenol (Lowry) method, double-antibody sandwich ELISA and qPCR were used to detect hemagglutinin, total protein, host cell protein (HCP) and host cell DNA (HCD) before and after purification. The recovery rate of virus antigen and the removal rate of impurities were calculated. The immunogenicity of the viruses purified with different media was analyzed using animal experiments. Difference in the purification efficacy of the two chromatography media was analyzed by t-test. Results:H5N1 influenza viruses purified by Capto Core700 or Sepharose 4FF showed the typical influenza virus morphology under transmission electron microscope. There was no significant difference in the recovery rate of hemagglutinin between the two chromatography media ( P>0.05), but compared with Sepharose 4FF, Capto Core700 had a higher removal rate of impurities (total protein, HCP, HCD) and the difference was statistically significant ( P<0.05). Animal experiments showed that the viruses purified by the two chromatography media had good immunogenicity. Conclusions:Compared with Sepharose 4FF chromatography medium, Capto Core700 could more effectively remove process-related impurities such as HCP, HCD and total protein without affecting the recovery rate of viral antigen. This study provided reference for the development of purification technology in the production of H5N1 influenza virus vaccine in MDCK cells.

Preparation and immunogenicity evaluation of recombinant influenza hemagglutinin trimer vaccine / 中华微生物学和免疫学杂志

Objective:To prepare a recombinant hemagglutinin trimer (HA-Tri) vaccine against influenza viruses and to study its immunogenicity in a mouse model.Methods:A stable CHO cell line that could express HA-Tri was constructed. Western blot, single radial immunodiffusion, protein particle size detection and N-glycosylation site analysis were performed for qualitative and quantitative analysis of the recombinant protein. According to the different treatment conditions such as dosage and adjuvant, BALB/c mice were divided into 11 groups and subjected to consistent immunization procedures. Serum neutralizing antibody titers were measured on 56 d after the first immunization to evaluate the immunogenicity of HA-Tri.Results:The constructed CHO cells could secret and express HA-Tri proteins. The HA-Tri proteins were biologically active and capable of forming precipitation rings in the single radial immunodiffusion. The particle size of HA-Tri was approximately 18.79 nm and 10 N-glycosylation sites were detected, including high mannose, complex glycoforms and heterozygous glycoforms. After prime-boost immunization, there was no statistically significant difference in the titers of neutralizing antibodies induced in mice by 3.75 μg of HA-Tri in combination with RFH01 adjuvant and 15 μg of monovalent vaccine stock solution ( P=0.431 2, U=36). Serum antibody titers in the HA-Tri+ RFH01 groups were higher than those in the corresponding HA-Tri groups without RFH01 adjuvant, and the highest titer was induced in the 15 μg HA-Tri+ RFH01 group, which was 1 280. Conclusions:The recombinant HA-Tri protein was successfully prepared. HA-Tri in combination with RFH01 adjuvant could induce humoral immune responses against influenza viruses in BALB/c mice, which would provide reference for the development of influenza virus recombinant subunit vaccines.

Effects of poly(A) tails with different lengths on mRNA expression in vitro and stability of transcription template in Escherichia coli / 中华微生物学和免疫学杂志

Objective:To investigate the effects of poly(A) tails with different lengths on mRNA expression in vitro and the passage stability of transcription template with poly (A) tail in Escherichia coli ( E. coli). Methods:Plasmids with poly(A) tails of 38, 60, 103, 125 and 126 (60 nt+ 6 nt spacer+ 60 nt) nt were designed and constructed. Then the plasmids were linearized by single enzyme digestion and used as transcription template for preparing enhanced green fluorescent protein (EGFP)-mRNA. EGFP-mRNA containing poly(A) tails of different lengths were transfected into 293T cells and the expression of EGFP was detected by flow cytometry. As to stability test, the template plasmids with poly (A) tail of 125 and 126 nt were transformed into E. coli TransStbl3 and Top10 competent cells. Seven clones were selected for culture and plasmid extraction, and then the plasmids were digested by restriction enzyme and detected by capillary electrophoresis. For passage stability, three correctly sequenced clones of each group were selected for continuous passage at 37℃, and the plasmids were extracted and digested every two generations for capillary electrophoresis. At the same time, the correctly sequenced clones of 125 nt group were also passaged at 30℃, and the plasmids were also extracted and digested every two generations for capillary electrophoresis. Results:The transcription templates with poly(A) tail of different lengths were successfully constructed. Flow cytometry showed that the fluorescence expression of the template plasmids with poly (A) tail of 103 and 125 nt were significantly higher than that of 38 and 60 nt. The fluorescence expression of the plasmid with poly (A) tail of 126 nt was significantly higher than that of all other groups. The percentages of stable sequences of the template plasmid with poly(A) tail of 125 nt in TransStbl3 and Top10 competent cells were 76% and 91%, respectively. The results of continuous passage showed that poly(A) tail of 125 nt could be stable to the 4th generation at 37℃ in both TransStbl3 and Top10 competent cells, and stable to the 16th and 10th generations at 30℃. The percentages of stable sequences of the template plasmid with poly(A) tail of 126 nt in TransStbl3 and Top10 competent cells were 95% and 48%, respectively. The results of continuous passage showed that poly(A) tail of 126 nt could be stable to the 12th generation at 37℃ in both TransStbl3 and Top10 competent cells.Conclusions:The length and composition of poly(A) tail in mRNA affected the expression of target protein. Adding a spacer with a length of 6 nt to poly(A) tail and low temperature culture were both helpful to improve the stability of the template plasmid, which provided a reference for the design and preparation of in vitro transcription template of mRNA vaccine.

Heterologous boost with mRNA vaccines against SARS-CoV-2 Delta/Omicron variants following an inactivated whole-virus vaccine

The coronavirus SARS-CoV-2 has mutated quickly and caused significant global damage. This study characterizes two mRNA vaccines ZSVG-02 (Delta) and ZSVG-02-O (Omicron BA.1), and associating heterologous prime-boost strategy following the prime of a most widely administrated inactivated whole-virus vaccine (BBIBP-CorV). The ZSVG-02-O induces neutralizing antibodies that effectively cross-react with Omicron subvariants following an order of BA.1>BA.2>BA.4/5. In naive animals, ZSVG-02 or ZSVG-02-O induce humoral responses skewed to the vaccines targeting strains, but cellular immune responses cross-react to all variants of concern (VOCs) tested. Following heterologous prime-boost regimes, animals present comparable neutralizing antibody levels and superior protection across all VOCs. Single-boost only generated ancestral and omicron dual-responsive antibodies, probably by "recall" and "reshape" the prime immunity. New Omicron-specific antibody populations, however, appeared only following the second boost with ZSVG-02-O. Overall, our results support a heterologous boost with ZSVG-02-O, providing the best protection against current VOCs in inactivated virus vaccine- primed populations.

Structural basis of a two-antibody cocktail exhibiting highly potent and broadly neutralizing activities against SARS-CoV-2 variants including diverse Omicron sublineages

SARS-CoV-2 variants of concern (VOCs), especially the latest Omicron, have exhibited severe antibody evasion. Broadly neutralizing antibodies with high potency against Omicron are urgently needed for understanding working mechanisms and developing therapeutic agents. In this study, we characterized previously reported F61, which was isolated from convalescent patients infected with prototype SARS-CoV-2, as a broadly neutralizing antibody against all VOCs including Omicron BA.1, BA.1.1, BA.2, BA.3 and BA.4 sublineages by utilizing antigen binding and cell infection assays. We also identified and characterized another broadly neutralizing antibody D2 with epitope distinct from that of F61. More importantly, we showed that a combination of F61 with D2 exhibited synergy in neutralization and protecting mice from SARS-CoV-2 Delta and Omicron BA.1 variants. Cryo-EM structures of the spike-F61 and spike-D2 binary complexes revealed the distinct epitopes of F61 and D2 at atomic level and the structural basis for neutralization. Cryo-EM structure of the Omicron-spike-F61-D2 ternary complex provides further structural insights into the synergy between F61 and D2. These results collectively indicated F61 and F61-D2 cocktail as promising therapeutic antibodies for combating SARS-CoV-2 variants including diverse Omicron sublineages.

Real-world study of the effectiveness of BBIBP-CorV (Sinopharm) COVID-19 vaccine in the Kingdom of Morocco

The Kingdom of Morocco approved BBIBP-CorV (Sinopharm) COVID-19 vaccine for emergency use on 22 January 2021 in a two-dose, three-to-four-week interval schedule. We conducted a case-control study to determine real-world BBIBP-CorV vaccine effectiveness (VE) against serious or critical hospitalization of individuals RT-PCR-positive for SARS-CoV-2 during the first five months of BBIBP-CorV use in Morocco. The study was conducted among adults 18-99 years old who were tested by RT-PCR for SARS-CoV-2 infection between 1 February and 30 June 2021. RT-PCR results were individually linked with outcomes from the COVID-19 severe or critical hospitalization dataset and with vaccination histories from the national vaccination registration system. Individuals with partial vaccination (<2 weeks after dose two) or in receipt of any other COVID-19 vaccine were excluded. Unadjusted and adjusted VE estimates against hospitalization for serious or critical illness were made by comparing two-dose vaccinated and unvaccinated individuals in logistic regression models, calculated as (1-odds ratio) * 100%. There were 348,190 individuals able to be matched across the three databases. Among these, 140,892 were fully vaccinated, 206,149 were unvaccinated, and 1,149 received homologous BBIBP-CorV booster doses. Unadjusted, full-series, unboosted BBIBP-CorV VE against hospitalization for serious or critical illness was 90.2% (95%CI: 87.8% - 92.0%). Full-series, unboosted VE, adjusted for age, sex, and calendar day of RT-PCR test, was 88.5% (95%CI: 85.8% - 90.7%). Calendar day- and sex-adjusted VE ranged from 93.9% to 100% for individuals <60 years, and was 53.3% for individuals 60 years and older. There were no serious or critical illnesses among BBIBP-CorV-boosted individuals. Effectiveness of Sinopharms BBIBP-CorV was consistent with phase III clinical trial results. Two doses of BBIBP-CorV was highly protective against COVID-19-associated serious or critical hospitalization in working-age adults under real-world conditions and moderately effective in older adults. Booster dose VE should be evaluated, as booster doses of BBIBP-CorV are recommended and are being used.

The incidence of COVID-19 infection following emergency use authorization of BBIBP-CORV inactivated vaccine in frontline workers in the United Arab Emirates.

Based on the findings from the Phase III clinical trials of inactivated SARS COV-2 Vaccine, (BBIBP-CORV) emergency use authorization (EUA) was granted for the vaccine to frontline workers in the UAE. A prospective cohort study was conducted among frontline workers to estimate the incidence rate and risk of symptomatic COVID-19 infection 14 days after the second dose of inoculation with BBIBP-CORV inactivated vaccine. Those who received two doses of the BBIBP-CORV vaccine in the period from 14th of September 2020 (first dose) to 21st of December 2020 (second dose) were followed up for COVID-19 infections. 11,322 individuals who received the two-dose BBIBP-CORV vaccine were included and were followed up post the second dose plus fourteen days. The incidence rate of symptomatic infection was 0.08 per 1000-person days (95% CI 0.07, 0.10). The estimated absolute risk of developing symptomatic infection was 0.97% (95% CI 0.77%, 1.17%). The confirmed seroconversion rate was 92.8%. There were no serious adverse events reported and no individuals suffered from severe disease. Our findings show that vaccinated individuals are likely to remain protected against symptomatic infection or becoming PCR positive for SARS COV 2 following the second dose of the vaccination.

Analysis of therapeutic effect and influencing factors of radiofrequency ablation for colorectal cancer liver metastases / 中华放射学杂志

Objective:To explore the efficacy and influencing factors of radiofrequency ablation (RFA) in the treatment of colorectal cancer liver metastases (CRLM).Methods:The clinical and imaging data of 281 patients (477 intrahepatic metastatic tumors) who received percutaneous RFA treatment in Sir Run Run Shaw Hospital, Zhejiang University School of Medicine from December 2009 to December 2020 were retrospectively analyzed. Factors that may affect the efficacy of RFA were recorded, including carcinoembryonic antigen (CEA), differentiation, extrahepatic metastasis, tumor location and size, complications and other information. Patients were followed up through hospital admissions, telephone, etc. The primary endpoints were overall survival (OS) and local tumor progression-free survival (LTPFS). Univariate and multivariate logistic regression models were used to identify predictors of residual tumor. Univariate and multivariate Cox proportional hazards regression were used to identify the influencing factors of LTPFS and OS. The median LTPFS and OS were estimated by the Kaplan-Meier curve and compared by the log-rank test.Results:After RFA, 68 (14.3%) tumor residues were observed. Multivariate logistic regression showed that the risk factors for residual tumor were size ≥20 mm, high-risk and perivascular location, and minimal ablative margin<5 mm. During the follow-up period, the main complication rate was 4.3% (12/281) and the fatality rate was 31.3% (88/281). At the same time, local tumor progression was found in 167 (35.0%) lesions post-RFA. The median time of LTPFS and OS estimated by the Kaplan Meier method were 35.0 (95%CI 26.53-43.48) and 44.0 (95%CI 29.70-58.30) months, respectively. The cumulative proportion of LTPFS and OS were 37.2% and 40.4% respectively in the 5th year. Multivariate Cox proportional hazard regression showed that CEA≥30 ng/ml, tumor size ≥20 mm, and minimal ablative margin<5 mm were risk factors for LTPFS; extrahepatic metastasis, tumor burden>30 mm, and lesion with minimal ablative margin<5 mm were independent risk factors for OS; re-intervention was an independent protective factor for OS.Conclusions:Adequate ablative margin and less tumor burden were beneficial to local tumor control and long-term survival of patients in the RFA treatment; the existence of extrahepatic metastasis was an important risk factor for OS, and re-interventional therapy was beneficial to extend OS.

Prokaryotic expression and serological analysis of the head domain of influenza A virus hemagglutinin / 中华微生物学和免疫学杂志

Objective:To express the head domain of influenza A virus hemagglutinin (HA) in a prokaryotic expression system and to evaluate its immunogenicity.Methods:The genes encoding the HA head domains of H1N1 and H3N2 influenza viruses were cloned into pET-22b(+ ) prokaryotic expression plasmid. After the induction with IPTG, the fusion proteins rH1N1-HA and rH3N2-HA containing HA head domain and His-tag were expressed and obtained from E. coli BL21. SDS-PAGE and Western blot was used to verify the expression of the recombinant proteins. Rabbits were immunized with multiple doses of the purified recombinant proteins to obtain polyclonal antibodies against the HA head domains of H1N1 and H3N2. The immunogenicity of the recombinant proteins was evaluated in BALB/c mice. Results:rH1N1-HA and rH3N2-HA induced protective antibodies (geometric mean titer ≥40) in mice and could be used as protective antigens. Polyclonal antibodies against rH1N1-HA and rH3N2-HA could be used as important materials for Western blot, ELISA and other immunological assays.Conclusions:The HA head domains prepared in this study could be used as protective antigens to induce protective antibodies in mice. Polyclonal antibodies against the HA head domains could be used for immunological and serological studies of influenza A viruses.

Early assessment of the safety and immunogenicity of a third dose (booster) of COVID-19 immunization in Chinese adults / 医学前沿

Inducing durable and effective immunity against severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) via vaccination is essential to combat the current pandemic of coronavirus disease 2019 (COVID-19). It has been noticed that the strength of anti-COVID-19 vaccination-induced immunity fades over time, which calls for an additional vaccination regime, as known as booster immunization, to restore immunity among previously vaccinated populations. Here we report a pilot open-label trial of a third dose of BBIBP-CorV, an inactivated SARS-CoV-2 vaccine (Vero cell), on 136 participants aged between 18 to 63 years. Safety and immunogenicity in terms of neutralizing antibody titers and cytokine/chemokine responses were analyzed as the main endpoint until day 28. While systemic reactogenicity was either absent or mild, SARS-CoV-2-specific neutralizing antibody titers rapidly arose in all participants within 4 weeks, surpassing the peak antibody titers elicited by the initial two-dose immunization regime. Broad increases of cellular immunity-associated cytokines and chemokines were also detected in the majority of participants after the third vaccination. Furthermore, in an exploratory study, a newly developed recombinant protein vaccine, NVSI-06-08 (CHO Cells), was found to be safe and even more effective than BBIBP-CorV in eliciting humoral immune responses in BBIBP-CorV-primed individuals. Together, these results indicate that a third immunization schedule with either homologous or heterologous vaccine showed favorable safety profiles and restored potent SARS-CoV-2-specific immunity, providing support for further trials of booster vaccination in larger populations.

Twelve-month specific IgG response to SARS-CoV-2 receptor-binding domain among COVID-19 convalescent plasma donors in Wuhan

To investigate the duration of humoral immune response in convalescent coronavirus disease 2019 (COVID-19) patients, we conduct a 12-month longitudinal study through collecting a total of 1,782 plasma samples from 869 convalescent plasma donors in Wuhan, China and test specific antibody responses. The results show that positive rate of IgG antibody against receptor-binding domain of spike protein (RBD-IgG) to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the COVID-19 convalescent plasma donors exceeded 70% for 12 months post diagnosis. The level of RBD-IgG decreases with time, with the titer stabilizing at 64.3% of the initial level by the 9th month. Moreover, male plasma donors produce more RBD-IgG than female, and age of the patients positively correlates with the RBD-IgG titer. A strong positive correlation between RBD-IgG and neutralizing antibody titers is also identified. These results facilitate our understanding of SARS-CoV-2-induced immune memory to promote vaccine and therapy development.

Neutralization of SARS-CoV-2 VOC 501Y.V2 by human antisera elicited by both inactivated BBIBP-CorV and recombinant dimeric RBD ZF2001 vaccines

Recently, the emerged and rapidly spreading SARS-CoV-2 variant of concern (VOC) 501Y.V2 with 10 amino acids in spike protein were found to escape host immunity induced by infection or vaccination. Global concerns have been raised for its potential to affect vaccine efficacy. Here, we evaluated the neutralization activities of two vaccines developed in China against 501Y.V2. One is licensed inactivated vaccine BBIBP-CorV and the other one is recombinant dimeric receptor-binding domain (RBD) vaccine ZF2001. Encouragingly, both vaccines largely preserved neutralizing titres, with slightly reduction, against 501Y.V2 authentic virus compare to their titres against both original SARS-CoV-2 and the currently circulating D614G virus. These data indicated that 501Y.V2 variant will not escape the immunity induced by vaccines targeting whole virus or RBD.

Time-series analysis of air pollution effects on diabetes related mortality / 环境与职业医学

Background Diabetes mellitus is a major public health issue at present. Previous studies have shown that ambient air pollution is a risk factor for diabetes. Objective This study aims to explore the acute effects of ambient air pollution on diabetes related death in Shanghai Jing’an District. Methods Daily air pollution data, meteorological data, and diabetes related mortality data in 2013−2019 in Shanghai Jing’an District were collected. A generalized additive model (GAM) was established to conduct time-series analysis on the short-term effect of ambient air pollution on diabetes related mortality, and gender- and age-stratified analysis on susceptibility of various groups to ambient air pollution exposures. Results For every 10 μg·m−3 increase of the concentrations of PM2.5, PM10, SO2, and NO2, the diabetes related mortality increased by 2.47% (95%CI: 1.56%−3.38%), 2.02% (95%CI: 1.29%−2.75%), 5.75% (95%CI: 2.99%−8.58%), and 3.93% (95%CI: 2.49%−5.39%) at lag05 respectively (P<0.05). In the stratified analysis, exposures to increased concentrations of PM2.5, PM10, SO2, and NO2 raised the mortality risks from diabetes in male, female, and ≥65 years oldgroups (P<0.05). However, the differences in mortality risks from diabetes due to air pollution within gender and age groups were statistically insignificant. Conclusion In Shanghai Jing'an District, the elevated levels of ambient air pollutants, including PM2.5, PM10, SO2, and NO2, are significantly associated with the increase of diabetes related mortality, and there are lag effects and cumulative effects. The ≥65 years olds are more susceptible to the impact of air pollution on diabetes related deaths.

Isolation and purification of neuraminidase from influenza vaccine and reference substance preparation / 中华微生物学和免疫学杂志

Objective:To establish a method for isolation and purification of neuraminidase from influenza vaccine and to prepare reference substance for quantitative detection of neuraminidase.Methods:Functional magnetic particles with specific affinity for neuraminidase were prepared. The method for separation and purification of neuraminidase was established based on the magnetic particles. The separation and purification conditions were optimized. The purity of neuraminidase was analyzed and the specificity was verified. The enzyme activity was determined and the protein was quantified.Results:The functional magnetic particles modified with 4-aminophenanthroline were successfully prepared and the method for isolation and purification of neuraminidase based on the magnetic particles was established. The purity of neuraminidase was 98.7%. The concentrations of neuraminidase isolated and purified from the monovalent stock solution of H1N1, H3N2, B/Victoria and B/Yamagate vaccines were 71.50, 100.58, 64.11 and 37.68 μg/ml, respectively, and the enzyme activity remained.Conclusions:The method for isolation and purification of influenza virus neuraminidase was established and the corresponding reference substance was prepared.

Immunogenicity of MDCK cell-based quadrivalent influenza split vaccine with different adjuvants in mice / 中华微生物学和免疫学杂志

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.

Correction: Hyperhomocysteinemia in ApoE-/- Mice Leads to Overexpression of Enhancer of Zeste Homolog 2 via miR-92a Regulation.

[This corrects the article DOI: 10.1371/journal.pone.0167744.].

The feasibility of convalescent plasma therapy in severe COVID-19 patients: a pilot study

Currently, there are no approved specific antiviral agents for 2019 novel coronavirus disease (COVID-19). In this study, ten severe patients confirmed by real-time viral RNA test were enrolled prospectively. One dose of 200 mL convalescent plasma (CP) derived from recently recovered donors with the neutralizing antibody titers above 1:640 was transfused to the patients as an addition to maximal supportive care and antiviral agents. The primary endpoint was the safety of CP transfusion. The second endpoints were the improvement of clinical symptoms and laboratory parameters within 3 days after CP transfusion. The median time from onset of illness to CP transfusion was 16.5 days. After CP transfusion, the level of neutralizing antibody increased rapidly up to 1:640 in five cases, while that of the other four cases maintained at a high level (1:640). The clinical symptoms were significantly improved along with increase of oxyhemoglobin saturation within 3 days. Several parameters tended to improve as compared to pre-transfusion, including increased lymphocyte counts (0.65x109/L vs. 0.76x109/L) and decreased C-reactive protein (55.98 mg/L vs. 18.13 mg/L). Radiological examinations showed varying degrees of absorption of lung lesionswithin 7 days. The viral load was undetectable after transfusion in seven patients who had previous viremia. No severe adverse effects were observed. This study showed CP therapy was welltolerated and could potentially improve the clinical outcomes through neutralizing viremia in severe COVID-19 cases. The optimal dose and time point, as well as the clinical benefit of CP therapy, needs further investigation in larger well-controlled trials. Significance StatementCOVID-19 is currently a big threat to global health. However, no specific antiviral agents are available for its treatment. In this work, we explored the feasibility of convalescent plasma (CP) transfusion to rescue severe patients. The results from 10 severe adult cases showed that one dose (200 mL) of CP was welltolerated and could significantly increase or maintain the neutralizing antibodies at a high level, leading to disappearance of viremia in 7 days. Meanwhile, clinical symptoms and paraclinical criteria rapidly improved within 3 days. Radiological examination showed varying degrees of absorption of lung lesions within 7 days. These results indicate that CP can serve as a promising rescue option for severe COVID-19 while the randomized trial is warranted.

A review of combined immunization: current research situation and its promising future / 中华流行病学杂志

Combined immunization consists of combined vaccines (including polyvalent vaccines) and simultaneous administration of vaccines, aiming to reduce unnecessary inoculating times for children, and to broaden immunization coverage and a significant larger group of population would be benefit from the Expanded Program on Immunization. In this review, we have summarized a list of research papers focused on combined immunization. By scrutinizing the safety and effectiveness outcomes of combined immunization, we provide some suggestions about upgrading the current immunization program as well as research and development of new combined vaccines.