With the development of bio-technological drugs, drug immunogenicity evaluation has become key factor of clarifying safety and efficacy of these drugs. It has become the focus to establish a stable and reliable evaluation system. Due to the advantages such as continuous real-time monitoring, surface plasmon resonance (SPR) technology has been widely used in bio-technological drugs immunogenicity assessments. Our study applied this technology to detect anti-drug antibody (ADA) of a recombinant human anti-rabies monoclonal antibody NM57 in the sera of 48 volunteers admitted in phase I clinical trials. This method could satisfy the basic requirements of detection of ADA.
Antibodies, Anti-Idiotypic ; analysis ; blood ; immunology ; Antibodies, Monoclonal ; analysis ; blood ; immunology ; Antibodies, Viral ; analysis ; blood ; immunology ; Humans ; Rabies virus ; immunology ; Recombinant Proteins ; analysis ; blood ; immunology ; Surface Plasmon Resonance

Avidin layer was bound on the substrate surface of Silicon wafer modified with aldehyde. The interaction between avidin and biotin was adopted for the immobilization of mouse monoclonal biotin-anti-M13 (antibody GP3)-labeled biotin. The surface was incubated in a solution containing phage M13KO7, which was trapped by the antibody GP3 with the interaction between phage M13KO7 and antibody GP3, resulting in a variation of layer thickness that was detected by imaging ellipsometry. The results showed a saturated layer of antibody GP3 with a thickness about 6.9 nm on the surface of the silicon wafer. The specific interaction between phage M13KO7 and antibody GP3 resulted in a variation of the layer thickness. The layer of phage M13KO7 bound with antibody GP3 was 17.5 nm in the concentration of 1.1 x 10(10) pfu/mL. Each variation of layer thickness corresponded to a concentration of phage M13KO7 in the range of 0.1 x 10(10) approximately 2.5 x 10(10) pfu/mL, with the sensitivity of 10(9) pfu/mL. Compared with other methods, the optical protein-chip requires only short measurement time, is label free, is a quantitative test, and can be visualized. This study could be significant on the investigation of interactions between the antibody and virus, and shows potential in the early diagnosis of virosis.
Animals ; Antibodies, Viral ; immunology ; Bacteriophage M13 ; immunology ; isolation & purification ; Mice ; Protein Array Analysis ; methods

OBJECTIVETo investigate hepatitis E virus (HEV) infection among pigs in Henan province.

METHODSA total of 623 swine sera, collected from 5 districts, were divided into two groups, under 3-month of age and over 3-month of age. They were tested for HEV antigen and antibody by using ELISAs, respectively. The sera positive for HEV antigen were tested for HEV RNA with RT-PCR. The positive products of RT-PCR were cloned and sequenced.

RESULTSThe positive rates of anti-HEV antibody of the groups under 3-month and over 3-month of age were 90.27% and 92.55%, respectively, without statistical difference, while those of HEV antigen were 15.93% and 5.69%, respectively, with significant difference. The positive rates of anti-HEV antibody and HEV antigen were significantly different among different districts. HEV RNA was detectable in 5 of 47 HEV antigen positive samples. The sequence analysis showed that in 4 of 5 specimens the sequence belonged to genotype 4 while in the remaining one the sequence was genotype 1.

CONCLUSIONThe prevalence rate of HEV infection in pigs was high in Henan province and the rate differed in different districts.

Animals ; Antibodies, Viral ; analysis ; immunology ; Antigens, Viral ; analysis ; immunology ; China ; Genotype ; Hepatitis E ; epidemiology ; immunology ; veterinary ; virology ; Hepatitis E virus ; genetics ; immunology ; isolation & purification ; Phylogeny ; RNA, Viral ; analysis ; genetics ; Sequence Analysis, DNA ; Swine ; virology ; Swine Diseases ; epidemiology ; immunology ; virology

Rubella virus (RV), one of pathogens in TORCH syndrome, can lead to anisotropy of the fetus, and therefore it is of great significance to screen RV infection among women at child-bearing age. At the present, the screening of RV infection is mainly based on the ELISA method, the specificity of RV antigens is very important for ELISA tests. The antigenicity of RV is closely associated with its structural proteins, including capsid protein C, and envelope glycoproteins E1 and E2, which are important surface antigens of RV. This paper reviews the advances in the studies on the structure features, immunogenicity and recombinant proteins of the three structural proteins.
Antibodies, Viral ; analysis ; Enzyme-Linked Immunosorbent Assay ; Recombinant Proteins ; immunology ; Rubella virus ; genetics ; immunology ; Viral Core Proteins ; genetics ; immunology ; Viral Envelope Proteins ; genetics ; immunology ; Viral Structural Proteins ; genetics ; immunology

OBJECTIVETo develop the monoclonal antibody against N protein of SARS virus and study its applicability.

METHODSBALB/c mice were immunized with recombinant N protein. Spleen cells were collected and infused with SP2/0 cell. The infused cells were screened for anti-N protein antibody with ELISA. The positive cells were cloned and injected into abdominal cavity. The antibodies were purified from ascites. The affinities of those purified antibodies were analyzed with ELISA. The ELISA for detection of SARS virus antigen was developed by using antibody with the highest affinity. Its sensitivity and specificity were also evaluated primarily.

RESULTSEleven monoclonal cells secreting antibody have been developed. Three of the 11 purified monoclonal antibodies had very high affinity to N protein, while 4 purified McAbs showed very weak reaction to N protein, the affinities of remaining 4 McAbs were in between. The ELISA for detection of SARS virus antigen was developed with McAb 7. Its sensitivity was about 31 PFU/ml and had no cross reaction with other respiratory viruses.

CONCLUSIONThe monoclonal antibody has good specificity and may be used to detect SARS virus antigen. However, its sensitivity is to be evaluated further with clinical samples from SARS patients, especially at acute phase.

Animals ; Antibodies, Monoclonal ; biosynthesis ; Antibodies, Viral ; biosynthesis ; Antigens, Viral ; analysis ; Humans ; Hybridomas ; Mice ; Mice, Inbred BALB C ; Nucleocapsid Proteins ; immunology ; SARS Virus ; immunology ; Sensitivity and Specificity

Animals ; Antibodies, Viral ; analysis ; immunology ; Hemorrhagic Fever with Renal Syndrome ; diagnosis ; immunology ; prevention & control ; Humans ; Periodicals as Topic ; Vaccination

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

OBJECTIVETo better understand the duplication of hepatitis B virus (HBV) in order to improve clinical diagnoses and treatments via quantitative measurement of HBV-DNA and comparison of correlation of HBV-DNA with HBeAg and anti-HBe.

METHODSFor 883 hepatitis B patients with positive HBsAg, HBV-DNA was measured by COBAS AMPLICOR HBV MONITOR reagent and COBAS AMPLICOR quantitative PCR instrument. Microparticle enzyme immunoassay analysis (MEIA) was then carried out with fully automatic enzyme immunoassay analysis instrument made by Abbott Axsym from the U.S. to measure HBeAg and anti-HBe. Correlation was analysed by SPSS.

RESULTS(1)Positive correlation between 690 HBV-DNA positive and HBeAg positive with r= 0. 505 (P< 0.01) was found with mean values as:HBV-DNA:7.12 x 10(12) copies/ml;HBeAg:218.31 S/CO. HBV-DNA:10(4) copies/ml, HBeAg: 104 S/CO; HBV-DNA: 10(5)-10(8) copies/ml, HBeAg: 112 S/CO; HBV-DNA: 10(9)-10(15) copies/ml, HBeAg: 252 S/CO. (2) No correlation was found between 193 HBV-DNA and anti-HBe + with r= -0.052(P= 0.477> 0.05) with Mean: HBV-DNA: 8.0x 10(10) copies/ml anti-HBe: 0.18 S/CO.

CONCLUSIONHBV-DNA and HBeAg appeared to have had linear correlation, showing that HBeAg> 100 S/CO,HBV-DNA> 10(4) copies/ml and hepatitis B virus were reproduced. However, HBV-DNA did not show linear correlation with anti-HBe as HBeAg negative and anti-HBe positive, the level of hepatitis B viral replication decrease slightly. But the virus load is still high. Infectivity can not neglect.

Antibodies, Viral ; analysis ; Carrier State ; DNA, Viral ; analysis ; Hepatitis B ; diagnosis ; genetics ; immunology ; Hepatitis B e Antigens ; analysis ; Hepatitis B virus ; genetics ; immunology ; Humans ; Immunoenzyme Techniques ; Polymerase Chain Reaction ; Viral Load ; Virus Replication

The lack of effective in vitro infection model for hepatitis E virus (HEV) has greatly hindered the quantitative analysis of neutralizing titers of anti-HEV antibodies and human sera, thus impeding further studies of HEV-stimulated antibody responses and the immunological mechanisms. In order to improve this situation, the infection of HepG2 cells that are inefficient for HEV replication was continuously monitored until the viral load reached the limit of detection on day 13, the results of which confirmed the feasibility of using this cell line to establish the infection model. Then, neutralization assays of five anti-HEV murine monoclonal antibodies and serum samples collected from four HEV vaccine recipients (collected before and after vaccination) were performed by 96 multi-channel parallel infections, nucleic acid extraction, and qPCR. The results showed that the cell model can be applied for quantitative evaluation of the neutralizing capacity of different antibodies and antiserum samples from HEV vaccine recipients. In this study, we have successfully established a high-throughput in vitro HEV replication model, which will prove to be useful for the evaluation of HEV vaccines and studies of HEV epitopes.
Animals ; Antibodies, Viral ; analysis ; immunology ; Hepatitis Antibodies ; analysis ; immunology ; Hepatitis E ; immunology ; virology ; Hepatitis E virus ; chemistry ; immunology ; physiology ; High-Throughput Screening Assays ; methods ; Humans ; Mice ; Mice, Inbred BALB C ; Neutralization Tests ; methods ; Virus Replication

Effective and tolerable vaccination is an essential strategy to prevent Japanese encephalitis (JE) in endemic areas. Although the live attenuated SA 14-14-2 JE vaccine (LAJEV) has been widely used since its introduction, the systemic data of LAJEV was very rarely available in Korea. We conducted the open-label, prospective cohort study to assess the immunogenicity and safety of this vaccine. Ninety subjects were enrolled, and LAJEV in a 2-dose primary series was given with a 12-month interval. Neutralizing antibody titers were measured before and after each vaccination, and active monitoring for adverse events was performed. After the first dose, 91.1% of subjects had seroprotection with a geometric mean titer (GMT) of 40.9. Seroprotection rate after the second dose was 97%, and GMT showed an increase of 6.5-fold. Most adverse events following immunization were self-limited, and no serious adverse events were reported until 42 days after each dose. The 2-dose administration of LAJEV in the primary immunization schedule appeared to be highly immunogenic and safe.
Antibodies, Neutralizing/analysis/immunology ; Antibodies, Viral/analysis/immunology ; Antibody Formation ; Child, Preschool ; Cohort Studies ; Encephalitis, Japanese/*prevention & control ; Female ; Humans ; Infant ; Japanese Encephalitis Vaccines/*immunology ; Male ; Prospective Studies ; Vaccination ; Vaccines, Attenuated/*immunology