Objective The study aims to investigate the immunological functions of the nucleocapsid (N) protein of the novel coronavirus Omicron (BA.1, BA.2) and evaluate the differences among different N proteins of mutant strains in immunogenicity. Methods By aligning sequences, the mutation sites of the Omicron (BA.1, BA.2) N protein relative to prototype strain of the novel coronavirus (Wuhan-Hu-1) were determined. The pET-28a-N-Wuhan-Hu-1 plasmid was used as template to construct pET-28a-BA.1/BA.2-N through single point mutation or homologous recombination. The three kinds of N protein were expressed in prokaryotic system, purified through Ni-NTA affinity chromatography, and then immunized into mice. The titer and reactivity of the polyclonal antibody, as well as the expression level of IL-1β and IFN-γ in mouse spleen cells, were detected using indirect ELISA and Western blot assay. Results The constructed prokaryotic expression plasmids were successfully used to express the Wuhan-Hu-1 N, BA.1 N, and BA.2 N proteins in E.coli BL21(DE3) at 37 DegreesCelsius for 4 hours. The indirect ELISA test showed that the titers of polyclonal antibody prepared by three N proteins were all 1:51 200. All three N proteins can increase the expression of IFN-γ and IL-1β cytokines, but the effect of Omicron N protein in activing two cytokines was more obvious than that of Wuhan-Hu-1 N protein. Conclusion The study obtained three new coronavirus N proteins and polyclonal antibodies, and confirmed that mutations in the amino acid sites of the N protein can affect its immunogenicity. This provides a basis for developing rapid diagnostic methods targeting N protein of different novel coronavirus variants.
Animals ; Mice ; SARS-CoV-2/genetics* ; Coronavirus Nucleocapsid Proteins/immunology* ; Nucleocapsid Proteins/isolation & purification* ; COVID-19/immunology* ; Antibodies, Viral/immunology* ; Mice, Inbred BALB C ; Interferon-gamma/metabolism* ; Interleukin-1beta/metabolism* ; Female ; Escherichia coli/metabolism* ; Mutation ; Humans

This study aims to establish an antibody detection method for porcine deltacoronavirus (PDCoV). The recombinant proteins PDCoV-N1 and PDCoV-N2 were expressed via the prokaryotic plasmid pColdII harboring the N gene sequence of the PDCoV strain CH/XJYN/2016. The reactivity and specificity of PDCoV-N1 and PDCoV-N2 with anti-PEDV sera were analyzed after the recombinant proteins were analyzed by SDS-PAGE and purified by the Ni-NTA Superflow Cartridge. Meanwhile, Western blotting and indirect immunofluorescence assay were carried out separately to validate the recombinant proteins PDCoV-N1 and PDCoV-N2. Finally, we established an indirect ELISA method based on the recombinant protein PDCoV-N2 after optimizing the conditions and tested the sensitivity, specificity, and reproducibility of the method. Then, the established method was employed to examine 102 clinical serum samples. The recombinant protein PDCoV-N2 showed low cross-reactivity with anti-PEDV sera. The optimal conditions of the indirect ELISA method based on PDCoV-N2 were as follows: the antigen coating concentration of 1.25 μg/mL and coating at 37 ℃ for 1 h; blocking by BSA overnight at 4 ℃; serum sample dilution at 1:50 and incubation at 37 ℃ for 1 h; secondary antibody dilution at 1:80 000 and incubation at 37 ℃ for 1 h; color development with TMB chromogenic solution at 37 ℃ for 10 min. The S/P value ≥ 0.45, ≤0.38, and between 0.45 and 0.38 indicated that the test sample was positive, negative, and suspicious, respectively. The testing results of the antisera against porcine epidemic diarrhea virus (PEDV), porcine circovirus 2 (PCV2), transmissible gastroenteritis virus (TGEV), foot-and-mouth disease virus (FMDV), and African swine fever virus (ASFV) showed that the S/P values were all less than 0.38. The testing results of the 800-fold diluted anti-PDCoV sera were still positive. The results of the inter- and intra-batch tests showed that the coefficients of variation of this method were less than 10%. Clinical serum sample test results showed the coincidence rate between this method and neutralization test was 94.12%. In this study, an ELISA method for the detection of anti-PDCoV antibodies was successfully established based on the truncated N protein of PDCoV. This method is sensitive, specific, stable, and reproducible, serving as a new method for the clinical diagnosis of PDCoV.
Animals ; Enzyme-Linked Immunosorbent Assay/methods* ; Swine ; Antibodies, Viral/blood* ; Recombinant Proteins/genetics* ; Deltacoronavirus/isolation & purification* ; Coronavirus Infections/virology* ; Swine Diseases/diagnosis* ; Coronavirus Nucleocapsid Proteins ; Sensitivity and Specificity

Adult ; Antibodies, Viral/isolation & purification* ; COVID-19/virology* ; Feces/chemistry* ; Female ; Humans ; Intestines/virology* ; Male ; RNA, Ribosomal, 16S/genetics* ; RNA, Viral/isolation & purification* ; SARS-CoV-2/pathogenicity*

Antibodies, Neutralizing ; Antibodies, Viral/isolation & purification* ; B-Lymphocytes/virology* ; COVID-19/virology* ; Humans ; Immunity/genetics* ; RNA, Viral/immunology* ; SARS-CoV-2/pathogenicity* ; Single-Cell Analysis

OBJECTIVE: To observe the clinical effect of plasma exchange and tocilizumab in treatment of patients with severe coronavirus disease 2019 (COVID-19). METHODS: Six patients with severe COVID-19 admitted in First Affiliated Hospital of Bengbu Medical College from January 25 to February 25, 2020. Three patients were treated with plasma exchange and three patients were treated with tocilizumab. The effect on excessive inflammatory reaction of plasma exchange and tocilizumab was observed. RESULTS: The C-reactive protein (CRP) and IL-6 levels were significantly decreased and the lymphocyte and prothrombin time were improved in 3 patients after treatment with plasma exchange; while inflammation level was not significantly decreased, and lymphocyte and prothrombin time did not improve in 3 patients treated with tocilizumab. CONCLUSIONS For severe COVID-19 patients with strong inflammatory reaction, plasma exchange may be preferred.
Antibodies, Monoclonal, Humanized ; administration & dosage ; Betacoronavirus ; isolation & purification ; Coronavirus Infections ; blood ; immunology ; therapy ; Cytokine Release Syndrome ; therapy ; Humans ; Pandemics ; Plasma Exchange ; standards ; Pneumonia, Viral ; blood ; immunology ; therapy ; Prothrombin Time ; Treatment Outcome

Objective: To explore the relationship between the status of HBsAg-positive infection of mothers and the non/low-response to hepatitis B vaccine of their infants. Methods: A total of 225 pairs of mothers and their infants were recruited in our cohort from June 2011 to July 2013. Infants were given three doses of hepatitis B vaccine at hour 24, first month and month 6(t)h respectively and were followed up for one year after birth. HBV serological markers and HBV DNA in the peripheral blood of both mothers and infants were detected by Electro-chemiluminescence immunoassay and fluorescence quantitative Polymerase Chain Reaction. Results: Six HBV infection models were detected in HBsAg-positive mothers, and "HBsAg (+), HBeAg (+), anti-HBc (+)" (model one) and "HBsAg (+), anti-HBe (+), anti-HBc (+)" (model two) accounted for 92.5%(208/225) of all the models. Rate of non/low-response to hepatitis B vaccine in infants born to mothers in model one was lower than those in model two, the differences are statistically significant (χ(2)=4.80, P=0.029). The rate of non/low-response to hepatitis B vaccine in infants showed a downward trend with the rising of HBeAg level in their mothers (χ(2)=4.86, P=0.028). Results from the unconditional logistic regression analysis showed that the HBeAg of the HBsAg-positive mothers was significantly correlated with the low risk of non/low-response to hepatitis B vaccine in infants (OR=0.598, 95%CI: 0.378-0.947). The positive rate of serum HBV DNA in HBsAg-positive mothers was 54.2%, while the rate of non/low-response to hepatitis B vaccine in infants born to HBV DNA positive mothers was similar to those infants born to HBV DNA negative mothers (χ(2)=0.22, P=0.640). Conclusions: "HBsAg (+), HBeAg (+), anti-HBc (+)" and "HBsAg (+), anti-HBe(+), anti-HBc (+)" were the common models seen in HBsAg-positive mothers, and the rate of non/low-response to hepatitis B vaccine was different between the two models. HBeAg of HBsAg-positive mothers might have positive effects on the immune response to hepatitis B vaccine in infants but the mechanisms remained not clear. HBV DNA of the HBsAg-positive mothers did not seem to be correlated with the immune response to hepatitis B vaccine in infants.
Adult ; Biomarkers/blood* ; DNA, Viral/blood* ; Diagnostic Tests, Routine ; Female ; Hepatitis B/prevention & control* ; Hepatitis B Antibodies/blood* ; Hepatitis B Surface Antigens/blood* ; Hepatitis B Vaccines/pharmacology* ; Hepatitis B e Antigens/blood* ; Hepatitis B virus/isolation & purification* ; Humans ; Infant ; Infectious Disease Transmission, Vertical/prevention & control* ; Mothers ; Pregnancy ; Pregnancy Complications, Infectious/virology*

OBJECTIVETo understand the distributions of DNA and neutralizing antibodies of human papillomavirus (HPV)16, 18 in 18-45 year-old women.

METHODSTotally, 1494 women were enrolled through multistage random sampling in Funing, Jiangsu province. Cervical exfoliated cells were collected from them for HPV DNA testing, and serum samples were taken from them for the detection of HPV16, 18 neutralizing antibodies by using pseudovirion-based neutralization assay(PBNA).

RESULTSAmong the 1494 women, 28(1.9%) and 188(12.6%) were positive for DNA and neutralizing antibody of HPV16 respectively, and 15(1.0%) and 60(4.0%) were positive for DNA and neutralizing antibody of HPV18, respectively. There were no significant differences in the detection rates of DNA and neutralizing antibody of HPV16, 18 among different age groups. About 16.7% of the women were infected with HPV16, 18, or both.

CONCLUSIONIn Funing county of Jiangsu province, most women aged 18-45 years has no immunity to HPV16 and 18, indicating that they are appropriate targets for HPV 16/18 vaccination.

Adolescent ; Adult ; Antibodies, Neutralizing ; isolation & purification ; Antibodies, Viral ; isolation & purification ; China ; DNA, Viral ; isolation & purification ; Female ; Human papillomavirus 16 ; immunology ; Human papillomavirus 18 ; immunology ; Humans ; Middle Aged ; Papillomavirus Infections ; prevention & control ; Papillomavirus Vaccines ; Young Adult

We wished to ascertain the prevalence as well as the genetic and antigenic variation of infectious bronchitis viruses (IBVs) circulating in the Guangxi Province of China in recent years. The S1 gene of 15 IBV field isolates during 2012-2013 underwent analyses in terms of the similarity of amino-acid sequences, creation of phylogenetic trees, recombination, and serologic identification. Similarities in amino-acid sequences among the 15 isolates of the S1 gene were 54.3%-99.6%, and 43.3%-99.3% among 15 isolates and reference strains. Compared with the vaccine strain H120, except for GX-YL130025, the other 14 isolates showed a lower similarity of amino-acid sequences of the S1 gene (65.1-81.4%). Phylogenetic analyses of the S1 gene suggested that 15 IBV isolates were classified into eight genotypes, with the predominant genotype being new-type II. Recombination analyses demonstrated that the S1 gene of the GX-NN130048 isolate originated from recombination events between vaccine strain 4/91 and a LX4-like isolate. Serotyping results suggested that seven serotypes prevailed during 2012-2013 in Guangxi Province, and that only one isolate was consistent with the vaccine strain H120 in serotype (which has been used widely in recent years). The serotype of recombinant isolate GX-NN130048 was different from those of its parent strains. These results suggested that not only the genotype, but also the serotype of IBV field isolates in Guangxi Province had distinct variations, and that increasing numbers of genotypes and serotypes are in circulation. We showed that recombination events can lead to the emergence of new serotypes. Our study provides new evidence for understanding of the molecular mechanisms of IBV variations, and the development of new vaccines against IBVs.
Animals ; Antibodies, Viral ; blood ; Chickens ; China ; Coronavirus Infections ; blood ; veterinary ; virology ; Genetic Variation ; Genotype ; Infectious bronchitis virus ; classification ; genetics ; immunology ; isolation & purification ; Molecular Sequence Data ; Phylogeny ; Poultry Diseases ; blood ; virology ; Sequence Homology, Amino Acid ; Spike Glycoprotein, Coronavirus ; chemistry ; genetics ; immunology

BACKGROUND/AIMS: The relationship between patient survival and biopsy-proven acute rejection (BPAR) in liver transplant recipients with hepatitis C remains unclear. The aims of this study were to compare the characteristics of patients with and without BPAR and to identify risk factors for BPAR. METHODS: We retrospectively reviewed the records of 169 HCV-RNA-positive patients who underwent LT at three centers. RESULTS: BPAR occurred in 39 (23.1%) of the HCV-RNA-positive recipients after LT. The 1-, 3-, and 5-year survival rates were 92.1%, 90.3%, and 88.5%, respectively, in patients without BPAR, and 75.7%, 63.4%, and 58.9% in patients with BPAR (P<0.001). Multivariate analyses showed that BPAR was associated with the non-use of basiliximab and tacrolimus and the use of cyclosporin in LT recipients with HCV RNA-positive. CONCLUSION: The results of the present study suggest that the immunosuppression status of HCV-RNA-positive LT recipients should be carefully determined in order to prevent BPAR and to improve patient survival.
Antibodies, Monoclonal/therapeutic use ; Biopsy ; Cyclosporine/therapeutic use ; Drug Therapy, Combination ; Genotype ; Graft Rejection/mortality/*prevention & control ; Hepacivirus/genetics/isolation & purification ; Hepatitis C/drug therapy/*virology ; Humans ; Immunosuppressive Agents/*therapeutic use ; *Liver Transplantation/adverse effects ; Polymerase Chain Reaction ; RNA, Viral/blood ; Recombinant Fusion Proteins/therapeutic use ; Recurrence ; Retrospective Studies ; Survival Rate ; Tacrolimus/therapeutic use

BACKGROUND/AIMS: To analyze the effects of preexisting lamivudine (LAM) resistance and applying antiviral treatment (adefovir [ADV] add-on LAM combination treatment) on long-term treatment outcomes, and comparing the clinical outcomes of antiviral-naïve chronic hepatitis B patients receiving entecavir (ETV) monotherapy. METHODS: This study enrolled 73 antiviral-naïve patients who received 0.5-mg ETV as an initial therapy and 54 patients who received ADV add-on LAM combination treatment as a rescue therapy from July 2006 to July 2010. RESULTS: During 24-month treatments, the decreases in serum log10HBV-DNA values (copies/mL) were significantly greater in the antiviral-naïve patients treated with ETV than the patients receiving ADV add-on LAM combination treatment. The biochemical response rates for alanine aminotransferase normalization at 6 months (ETV) and 12 months (ADV add-on LAM) were 90.4% (66/73) and 77.8% (42/54), respectively (P=0.048). A Kaplan-Meier analysis indicated that the rates of serologic response, viral breakthrough, and emergence of genotypic resistance did not differ significantly between the two patient groups. There were also no significant intergroup differences in the rates of disease progression (PD) and new development of hepatocellular carcinoma (HCC). CONCLUSION: The long-term clinical outcomes of antiviral-naïve patients treated with ETV and LAM-resistant patients receiving ADV add-on LAM combination treatment were comparable in terms of the emergence of HCC and disease progression.
Adenine/*analogs & derivatives/pharmacology/therapeutic use ; Adult ; Alanine Transaminase/blood ; Antibodies, Viral/blood ; Antiviral Agents/*therapeutic use ; DNA, Viral/blood ; Disease Progression ; Drug Resistance, Viral/drug effects ; Drug Therapy, Combination ; Female ; Follow-Up Studies ; Genotype ; Guanine/analogs & derivatives/pharmacology/therapeutic use ; Hepatitis B e Antigens/blood ; Hepatitis B virus/drug effects/genetics/isolation & purification ; Hepatitis B, Chronic/*drug therapy ; Humans ; Lamivudine/pharmacology/therapeutic use ; Male ; Middle Aged ; Organophosphonates/pharmacology/*therapeutic use ; Treatment Outcome