A real-world study on the effectiveness of BBIBP-CorV and CoronaVac in Nanjing area.

Since the advent of COVID-19 vaccine, the long-term monitoring and evaluation of vaccine effectiveness worldwide has never stopped. Real-world research of the mainstream vaccines in China (BBIBP-CorV and CoronaVac) is extremely valuable as a supplement to clinical research data. Venous blood of this study was collected from 111 blood donors and from 6 volunteers, who had received 2 doses of SAR-CoV-2 vaccine. Cross-sectional study and cohort study was adopted. Venous blood of 11 COVID-19 convalescent plasma donors was collected as a positive control. The seroconversion rate of neutralizing antibodies in 111 vaccine recipients was 90.99% (101/111); The level of SAR-CoV-2 antibodies peaked around 28 days after inoculation, then fast descended followed by gentle descended until it was still detectable around 280 days later. The changes in antibody levels were similar to those of the 6 participants and those of convalescent plasma donors after infection. 5 of the 6 participants still maintained a high level of neutralizing antibodies (> 60% of the peak value) around 28 days after receiving 2 doses of vaccine; one participant had an antibody reaction that was almost always negative for 4 weeks. BBIBP-CorV and CoronaVac can produce good immune effects in most vaccinators aged 20 to 59 years in Nanjing area. Nevertheless, significant individual discrepancies of the humoral immunity are still existed.

Prevalence of antibody to hepatitis B surface antigen among qualified blood donors in Nanjing, China.

Universal infant hepatitis B vaccination has been implemented more than three decades. This study aimed to determine the prevalence of antibodies to hepatitis B surface antigen (anti-HBs) and to hepatitis B core antigen (anti-HBc) in qualified blood donors in Nanjing, China. Plasmas of 815 qualified blood donors, collected from February through May 2019, were measured for anti-HBs and anti-HBc by enzyme-linked immunosorbent assay. There were 449 (55.1%) male and 366 (44.9%) female blood donors, with a median age of 28.9 years (18-60). The seroprevalence of anti-HBs was 58.8%, with no significant difference in different genders and different age groups. The overall prevalence of anti-HBc was 7.0%, with an increasing trend with age, from 0% in 18-20 years old group to 17.9% in 51-60 years old group (χ2 = 46.7965, p < .0001). The prevalence of anti-HBc in donors born after the implementation of universal hepatitis B vaccination was significantly lower than that in donors born before (1.0% vs 15.5%; χ2 = 63.6033, p < .0001). Our data suggest that more than half of the blood donors in Nanjing are anti-HBs positive. Since a blood recipient usually receives more than one unit of red blood cells or plasma, passively acquired anti-HBs in blood recipients may neutralize hepatitis B virus potentially presented in blood donors with occult hepatitis B infection. In addition, the presence of anti-HBs and/or anti-HBc in blood donors may cause unique hepatitis B serological profile in blood recipients.

Blood Donation Fear, Perceived Rewards, Self-Efficacy, and Intention to Return Among Whole Blood Donors in China: A Social Cognitive Perspective.

With the increasing demand from aging population and seasonal blood shortage, recruiting and retaining blood donors has become an urgent issue for the blood collection centers in China. This study aims to understand intention to donate again from a social cognitive perspective among whole blood donors in China through investigating the association between the blood donation fear, perceived rewards, self-efficacy, and intention to return. A cross-sectional survey was conducted in six cities, which are geographically and socioeconomically distinct areas in Jiangsu, China. Respondents completed a self-administrated questionnaire interviewed by two well-trained medical students. A total of 191 blood donors were included in the current study. Descriptive analysis, correlation analysis, and a generalized linear regression model were used to explore the association between demographic characteristics, psychological factors, and intention to donate again. After controlling other covariates, donors with higher fear scores reported lower intention to return (p = 0.008). Association between self-efficacy and intention to return was statistically significant (p < 0.001), whereas the association between intrinsic rewards (p = 0.387), extrinsic rewards (p = 0.939), and intention to return were statistically insignificant. This study found that either intrinsic rewards or extrinsic rewards are not significantly associated with intention to donate again among whole blood donors in China, and fear is negatively associated with intention to donate again. Therefore, purposive strategies could be enacted beyond appeals to rewards and focus on the management of donors' fear.

Platelet concentrate and type II IL-1 receptor are risk factors for allergic transfusion reactions in children.

PURPOSE: Allergic transfusion reactions (ATRs) are immunological reactions after transfusion. Interleukin-1 (IL-1) is a critical regulator for human diseases. We performed this study to investigate the association of type II IL-1 decoy receptor (IL1R2) expression with ATRs in children. METHODS: Children received blood transfusions between January and December 2019 were included. The age, sex, number and type of blood transfusion, allergic history, and medical history were collected and statistically analyzed. The blood samples were collected from children with and without ATRs for detecting the relative expression IL1R2 mRNA. Logistics regression analysis was performed to identify the risk factors for ATRs in children. The area under the receiver operating characteristic (ROC) curve (AUC) was used to evaluate the predictive performance of risk factors. RESULTS: Totally, 28,840 transfusions in 20,230 children, with 236 ATRs (0.82%) in 117 patients (0.58%) were included. ATRs were common in children at the hematology-oncology department, in children received higher number of blood transfusions, and older children. Platelet concentrate induced a higher incidence of ATRs (3.31%) than red cell concentrate (0.22%, p < 0.0001). After the transfusion, IL1R2 mRNA level was higher in the blood samples in children with ATRs than those without ATRs (p < 0.0001). Logistics regression analysis indicated that platelet concentrate (95% CI 3.555, 293.782) and IL1R2 expression (95% CI 1.171 × 102, 1.494 × 104) were independent risk factors for ATRs in children. IL1R2 expression had high performance in predicting ATRs (AUC = 0.998, 100% sensitivity and 98.85% specificity). CONCLUSION: High IL1R2 expression level in children who received blood transfusions may predict the morbidity of ATR.

Anti-SARS-CoV-2 virus antibody levels in convalescent plasma of six donors who have recovered from COVID-19.

BACKGROUND: Anti-SARS-CoV-2 virus antibody levels in convalescent plasma (CP), which may be useful in severe Anti-SARS-CoV-2 virus infections, have been rarely reported. RESULTS: A total of eight donors were considered for enrollment; two of them were excluded because of ineligible routine check. Of the six remaining participants, five samples were tested weakly positive by the IgM ELISA. Meanwhile, high titers of IgG were observed in five samples. The patient treated with CP did not require mechanical ventilation 11 days after plasma transfusion, and was then transferred to a general ward. CONCLUSIONS: Our serological findings in convalescent plasma from recovered patients may help facilitate understanding of the SARS-CoV-2 infection and establish CP donor screening protocol in COVID-19 outbreak. METHODS: Anti-SARS-CoV-2 antibodies including IgM and IgG were measured by two enzyme-linked immunosorbent assays (ELISA) in convalescent plasma from six donors who have recovered from coronavirus disease 2019 (COVID-19) in Nanjing, China. CP was also utilized for the treatment of one severe COVID-19 patient.

Prevalence of hepatitis E virus in Chinese blood donors.

OBJECTIVE: To investigate the prevalence of hepatitis E virus (HEV) antibodies and RNA in voluntary blood donors, in China. METHODS: Serum samples from blood donors were collected sequentially at six blood donation centres in five geographical regions of China. Donors were stratified between two groups according to their serum alanine aminotransferase (ALT) concentration (≤ 40 U/l and >40 U/l. Enzyme-linked immunosorbent assay and reverse transcription-polymerase chain reaction were used to quantify anti-HEV antibodies and RNA, respectively. RESULTS: In total, 21.1% (172/816) of donors were positive for anti-HEV immunoglobulin (Ig) G (elevated ALT samples group 18.9% [85/450]; normal ALT group 23.8% [87/366]), and 0.5% (four of 816) donors were positive for anti-HEV IgM (elevated ALT group 0.9% [four of 450]; normal ALT group 0% [none of 366]). The rate of anti-HEV IgG seropositivity was significantly higher in male than in female donors. No serum sample tested positive for HEV RNA. CONCLUSION: The prevalence of anti-HEV antibodies in blood donors in China is high, regardless of ALT concentration.

[Development of standardization platform for optical density value based on an improved method].

Due to the high variation in test results of indirect enzyme-linked immuno sorbent assay (ELISA) and complicated steps involved in the process of standardization, a platform used for standardizing the test results from indirect ELISA was developed. The platform was designed based on 'Improved Standardization Method for Optical Density' (I-STOD). Gauss-Newton iteration was applied to estimate parameters in a standard formula. Programming Language VB was used for developing interface of platform. The results indicated that the validity of experiment could be verified through platform. A well determined scope of standardization could be generated. The sample with concentration within the scope was standardized and the degree of dilution was calculated for those outside the scope. The platform was successfully developed which normalized the process of standardization. The function provides the researchers with an effective and convenient tool for quickly achieving standardization of ELISA test results.

Prevalence and prevalence trends of transfusion transmissible infections among blood donors at four Chinese regional blood centers between 2000 and 2010.

BACKGROUND: In China, high prevalence of HBV and HCV parallels with the growing epidemic of syphilis and HIV in the general population poses a great threat to blood safety. This study investigated the prevalence of serologic markers for transfusion transmissible infections (TTIs) among four Chinese blood centers. METHODS: We examined whole blood donations collected from January 2000 through December 2010 at four Chinese blood centers. Post-donation testing of TTIs (HIV, HBV, HCV and syphilis) were conducted using two different enzyme-linked immunosorbent assay kits for each seromarker. The prevalence of serologic markers for TTIs (%) was calculated and additional analysis was conducted to examine donor characteristics associated with positive TTIs serology. RESULTS: Of the 4,366,283 donations, 60% were from first-time donors and 40% were from repeated donors. The overall prevalence of HIV, HBsAg, HCV and syphilis was 0.08%, 0.86%, 0.51% and 0.47%, respectively. The prevalence profile of TTIs varied among different blood centers and appeared at relatively high levels. Overall, the prevalence of HBsAg and HCV demonstrated a decline trend among four blood centers, while the prevalence of HIV and syphilis displayed three different trends: constantly steady, continually increasing and declining among different centers. CONCLUSIONS: This study reflects the risk of TTIs has been greatly reduced in China, but blood transfusion remains an ongoing risk factor for the spread of blood-borne infections, and further work and improvements are needed to strengthen both safety and availability of blood in China.

l-Theanine prevents alcoholic liver injury through enhancing the antioxidant capability of hepatocytes.

l-Theanine is a unique amino acid in green tea. We here evaluated the protective effects of l-theanine on ethanol-induced liver injury in vitro and in vivo. Our results revealed that l-theanine significantly protected hepatocytes against ethanol-induced cell cytotoxicity which displayed by decrease of viability and increase of LDH and AST. Furthermore, the experiments of DAPI staining, pro-caspase3 level and PARP cleavage determination indicated that l-theanine inhibited ethanol-induced L02 cell apoptosis. Mechanically, l-theanine inhibited loss of mitochondrial membrane potential and prevented cytochrome c release from mitochondria in ethanol-treated L02 cells. l-Theanine also prevented ethanol-triggered ROS and MDA generation in L02 cells. l-Theanine restored the antioxidant capability of hepatocytes including GSH content and SOD activity which were reduced by ethanol. In vivo experiments showed that l-theanine significantly inhibited ethanol-stimulated the increase of ALT, AST, TG and MDA in mice. Histopathological examination demonstrated that l-theanine pretreated to mice apparently diminished ethanol-induced fat droplets. In accordance with the in vitro study, l-theanine significantly inhibited ethanol-induced reduction of mouse antioxidant capability which included the activities of SOD, CAT and GR, and level of GSH. These results indicated that l-theanine prevented ethanol-induced liver injury through enhancing hepatocyte antioxidant abilities.

[Mode and size of HPA-typed platelet apheresis donor bank in Chinese Han population].

This study was purposed to determine the mode and size of human platelet antigens (HPA) typed platelet apheresis donor bank. The published data of HPA distribution collected from Chinese Han population of 16 provinces were analyzed. The combined data were tested with the Hardy-Weinberg equilibrium. The results showed that the bb homozygote was not detected in HPA-1, -4, -6, -10, and b gene was not found in HPA-7-9, 11-14, -16. There were 648 combined HPA 1-16 genotypes in Chinese Han population, and the cumulative frequency of 42 combinations higher than 0.001 were 0.9763. The highest frequency (0.2012) in combination was HPA-(7-8-9-11-12-13-14-16) aa - (1-4-5-6-10) aa-2aa-3ab-15ab. The probability of HPA dual antigen mismatch in HPA-15, -3 and -2 was higher than the 0.1, and the probability in the HPA-1, -5, and -6 was between 0.01 - 0.1. The probability of full-match in HPA1-16 antigens was 0.3195 in Chinese Han population after the random blood transfusion. According to the curve drawn by donor number (N) versus frequency (F), the regression equation LogN = -0.4394 x Ln (F) +0.4324 was derived at P = 95%. If the derived frequency (product of HPA frequency and ABO frequency) is 0.005, then the N should be 576.07 at least in Chinese Han population. It is concluded that the mode of regional, multi-center database of HPA-typed platelet apheresis donor bank may be acceptable in Chinese Han population, and the suitable number of HPA-typed platelet donor in one bank may be 600. Therefore, the bank can be used to treat the platelet transfusion refractoriness (PTR) caused by HPA-15, 3 and 2 mismatch mainly, and can be expanded effectively in similar genetic background to deal with the low-frequency HPA antigens mismatch. The number of HPA-typed platelet apheresis donor influences not only on the frequency of HPA, but also on the frequency of ABO group.

[Polymorphism of human killer cell immunoglobulin-like receptor gene in Chinese Jiangsu Han population].

This study was purposed to investigate the distribution of killer cell immunoglobulin-like receptor(KIR)in Jiangsu Han population of China. KIR genomic typing were analyzed by PCR-SSP typing methods in 269 randomly unrelated healthy individuals. The results showed that all 16 known KIR genes were found in Jiangsu Han population, the total KIR genes found in Jiangsu Han population were 34 genes. Out of 34 KIR found genotypes, 15 genotypes (AA1, BX2, BX3, BX4, BX5, BX6, BX8, BX9, BX11, BX13, BX33, BX68, BX69, BX70, BX75) had also been identified in Zhejiang and Hong Kong populations, otherwise, 19 genotypes (BX10, BX12, BX17, BX23, BX26, BX27, BX28, BX31, BX35, BX42, BX47, BX57, BX72, BX74, BX79, BX154, BX188, BX231, BX370) had never been observed in Zhejiang and Hong Kong populations. The rare allele BX42 (detected only in Greece population) and BX231 (detected only in Sweden population) and BX370 (detected only in Macedonia population) were identified in Jiangsu Han population. In conclusion, all 16 known KIR genes were detected in Jiangsu Han population, the total 34 KIR genotypes are found in Jiangsu province, among them the BX42, BX231 and BX370 are rare KIR genotypes.

The false-positive and false-negative predictive value of HIV antibody test in the Chinese population.

OBJECTIVES: To analyse the relationship between the false-positive/false-negative predictive value (FPPV/FNPV) of the HIV-antibody (HIV-Ab) test and prevalence in different Chinese population groups. METHODS: HIV prevalence among different population groups was obtained by a screening survey of blood donors and the national HIV/AIDS surveillance programme in China. Given the sensitivity and specificity of a test kit and the prevalence of HIV infection, the estimated values of FPPV/FNPV were calculated using Bayes' formula. The actual value of FPPV of blood donors was obtained by screening 1,195,286 blood donors. RESULTS: This study indicates that the FPPV of HIV-Ab enzyme-linked immunosorbent assay (ELISA) assays varies widely in different Chinese populations: about 99.5% in the blood donor population, but only 3.2% in the injecting-drug users in high-risk areas. In 1,195,286 sera specimens from the blood donors, 2439 specimens were HIV-Ab positive by third ELISA, and 11 HIV cases were confirmed by Western blot. The HIV prevalence of the blood donor population in this survey was 0.0009% (11/1,195,286), but the HIV-Ab positive rate of third ELISA is 0.2% (2439/1,195,286) and 222 times higher than the prevalence. CONCLUSIONS: Evaluation of HIV prevalence through the HIV-Ab positive rate by third ELISA will significantly overestimate the true prevalence in a low-prevalence population. Individual HIV-infection status should be taken into consideration when analysing the results of HIV-Ab tests in a population with low infection.

[Influence of repeated platelet donation on megakaryopoiesis in donors].

To explore influence of platelet donation on donor's megakaryocytopoiesis, platelet counts and plasma concentrations of thrombopoietin (TPO), interleukin-3 (IL-3), IL-6 and nitric oxide (NO) were determined in 42 frequent platelet donors (undergoing plateletpheresis more than once a month for 24 months and their mean platelet yield of collection was 2.5 x 10(11)), in 62 limited platelet donors (undergoing plateletpheresis less than once a month for 24 months) after a donation-free period of > 5 weeks and in 40 whole blood donors who never undergoing plateletpheresis after a donation-free period of > 6 months. The results showed that the TPO levels was significantly lower in frequent platelet donors than in limited platelet donors (P < 0.01) and whole blood donors (P < 0.01). There were no significant differences between three groups in platelet counts, IL-3, IL-6 and NO. These findings suggest that the number of megakarocytes significantly increased in frequent platelet donors.

[Analysis of serologic typing error for HLA-A and HLA-B in Chinese].

Serological mistypings of HLA-A and HLA-B in 27 cases were analyzed. The results showed that for HLA-A and HLA-B typing, the rates of incorrect antigen assignments were significantly higher than rates of antigen misses (P < 0.05), but there was no significant difference between HLA-A and HLA-B typings. The frequencies of miss-assigned HLA-A and HLA-B specificities were A1 (66.7%), A3 (50.0%), A11 (13.5%), A9 (11.8%), A19 (7.1%), and B16 (50.0%), B48 (43.9%), B15 (16.7%), B40 (11.1%), B13 (10.0%) and B17 (9.1%). In conclusion, the serologic and DNA-based typing techniques should be reciprocally complementary in HLA-A and HLA-B typing.