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

OBJECTIVETo prepare monoclonal antibodies specific for M1 protein of H5N1 subtype human influenza virus, this work may provide new tool in rapid diagnosis and study of type A influenza virus.

METHODSBALB/c mice were immunized with purified recombinant H5N1 (A/Anhui/1/2005)/M1 protein expressed in E. coli. Spleen cells of the immunized mice were fused with sp2/0 cells to produce hybridoma cell lines. ELISA was performed to identify the monoclonal antibody against M1 protein of H5N1. Immunofluorescence assay (IFA) were applied to identify the specificity of these antibodies.

RESULTSThree hybridoma cell lines steadily secreting anti-H5N1/M1 McAb were obtained, and their cross reactivity was confirmed by cross-reaction test and IFA.

CONCLUSIONMonoclonal antibodies immunized with H5N1 subtype influenza virus M1 protein are cross-reactive, which can be used to detect different subtype of influenze virus type A.

Animals ; Antibodies, Monoclonal ; analysis ; immunology ; Antibodies, Viral ; analysis ; immunology ; Cell Line ; Cross Reactions ; Dogs ; Humans ; Influenza A Virus, H5N1 Subtype ; genetics ; immunology ; Influenza, Human ; immunology ; virology ; Mice ; Mice, Inbred BALB C ; Viral Matrix Proteins ; genetics ; immunology

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

OBJECTIVETo prepare monoclonal antibodies (McAbs) against VP1 capsid protein of Enterovirus 71.

METHODSTwo peptides, SP55 and SP70, containing amino acid 163-177 and 208-222 of VP1, were synthesized respectively. Immunized BALB/c mice with the synthetic peptides to establish the hybridoma cell strains secreting specific McAb to VP1. After the specific McAbs were prepared, identified and analyzed the titer by indirect ELISA assay. The positive clones were selected and their neutralization titer were determined by neutralization test.

RESULTSTwo high titered anti-VP1 antibodies secreted by the hybridoma cells showed good neutralization reaction with enterovirus 71 on RD cells, and the neutralization titer were 1:8 and 1:16 respectively.

CONCLUSIONTwo high titered anti-VP1 antibodies, with good neutralization activity, secreted by the hybridoma cells, which lays the foundation for further study.

Animals ; Antibodies, Monoclonal ; analysis ; immunology ; Antibodies, Viral ; analysis ; immunology ; Capsid Proteins ; analysis ; immunology ; Enterovirus ; chemistry ; immunology ; Enterovirus Infections ; diagnosis ; immunology ; virology ; Enzyme-Linked Immunosorbent Assay ; Humans ; Male ; Mice ; Mice, Inbred BALB C ; Neutralization Tests

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