OBJECTIVETo establish a three-step purification method of preparative-scale antiCD20 (Fab')2 using AKTA prime.

METHODSAntiCD20 (Fab')2 was extracted by hyperosmotic solution and then purified by CM sepharose FF, phenyl sepharose FF, and protein G sepharose FF.

RESULTSAround 8 mg anti-CD20 (Fab')2, whose purification was 96.678%, was purified. The antigen-binding activity of antiCD20 (Fab')2 was similar to that of antiCD20 (Fab')2 purified by protein G sepharose FF and S-100.

CONCLUSIONThe three-step purification method can obtain high-purity preparative-scale antiCD20 (Fab')2 in a simple way.

Antibodies ; immunology ; isolation & purification ; Antigens, CD20 ; immunology ; Chromatography ; methods ; Humans ; Immunoglobulin Fab Fragments ; immunology ; isolation & purification

OBJECTIVETo analyze the characteristic of T cell response to specific antigen proteins in patients with hepatitis B virus infection.

METHODS76 cases were recruited, including four groups, acute hepatitis B (AHB), active phase of chronic hepatitis B (CHB), inactive HBV carriers (AsC) and past HBV infection. T cell responses stimulated by 3 antigen specific proteins of HBV were detected using enzyme linked immunospot (ELISPOT) assay.

RESULTS(1) There were no significant difference in frequencies to HBsAg, HBcAg and HBeAg in AHB and CHB. The frequencies to HBsAg and HBcAg in AsC were lower than that to HBeAg, and the frequencies to HBsAg in group of past HBV infection were significantly lower than that to HBcAg and HBeAg. (2) The frequencies to HBsAg in AHB and CHB both were higher than in group of past HBV infection. The frequencies to HBcAg of AHB, CHB and AsC were higher than that of group of past HBV infection. (3) There were no significant difference in magnitude to HBsAg, HBcAg and HBeAg in AHB and AsC. In CHB, the magnitude to HBsAg was lower than that to HBcAg. The magnitude of in group of past HBV infection were HBcAg > HBeAg > HBsAg. (4) In four groups, the sequence of the magnitude to HBsAg from high to low was AHB, CHB, group of past HBV infection and AsC. The magnitude to HBcAg in of AsC was lower than other three groups. As to the magnitude to HBeAg, the difference was no significant between any two groups except between AHB and CHB.

CONCLUSIONSThe T cell responses in group of AsC to HBeAg were the highest, while the T cell responses to HBcAg were the highest in group of other groups.

Hepatitis B ; immunology ; virology ; Hepatitis B Antibodies ; immunology ; Hepatitis B Core Antigens ; immunology ; Hepatitis B Surface Antigens ; immunology ; Hepatitis B e Antigens ; immunology ; Hepatitis B virus ; immunology ; isolation & purification ; Humans ; T-Lymphocytes ; immunology

OBJECTIVETo establish an improved procedure for isolation and identification of epitopes from a random peptide library displayed on the bacterial surface.

METHODSEpitopes were screened from FliTrx random peptide library by a monoclonal antibody 3B9 against HBV-PreS2 protein. The enrichment was monitored in each round. Higher affinity clones were obtained by increasing the washing strength and randomly selected for sequencing and Western blot analysis.

RESULTSClones specifically binding to antibody were enriched in each round. Ten sequences were obtained from sixteen sequenced clones, seven of them contained the common motif RXRGXY with high homogeneity to 135-140 amio acids in HBV-PreS protein and have positive results in Western blot analysis. The other three sequences have no typical motif RXRGXY and showed different Western blot results.

CONCLUSIONSIt's easy and quick to drive epitopes from a random peptide library displayed on the bacterial surface.

Amino Acid Sequence ; Animals ; Antigens, Viral ; immunology ; Bacterial Proteins ; immunology ; Flagellin ; immunology ; Hepatitis B Surface Antigens ; genetics ; immunology ; isolation & purification ; Immunodominant Epitopes ; immunology ; Molecular Sequence Data ; Peptide Library ; Protein Precursors ; genetics ; immunology ; isolation & purification

OBJECTIVETo evaluate the accuracy of the Helicobacter pylori (H. pylori) stool antigen (HpSA) test and ImmunoCard STAT HpSA in the primary diagnosis of H. pylori infection.

METHODSWe searched Medline (1966-2007.4), EMbase (1985-2007.4), Chinese Journals Full-text Database (CJFD) (1994-2007) etc. to identify Clinical Trials of ImmunoCard STAT HpSA for the primary diagnosis of H. pylori infection. Meta-analysis was conducted using the method recommended by The Cochrane Collaboration Center.

RESULTSEleven trials were included with pooled sensitivity, pooled specificity as 0.93 (95% CI: 0.91-0.94), 0.93 (95% CI: 0.90- 0.95), respectively. Pooled positive likelihood ratio and pooled negative likelihood ratio were 12.01 (95% CI: 8.90-16.19), 0.08 (95% CI: 0.07-0.11), respectively with the pooled diagnostic odds ratio as 160.14(95% CI :100.43-255.34). The area under the summary receiver operating characteristic (SROC) was 0.974 +/- 0.005.

CONCLUSIONImmunoCard STAT HpSA appeared to be an accurate non-invasive method for the initial diagnosis of H. pylori infection.

Antigens, Bacterial ; immunology ; Feces ; microbiology ; Helicobacter Infections ; diagnosis ; immunology ; Helicobacter pylori ; immunology ; isolation & purification ; pathogenicity ; Reagent Kits, Diagnostic ; Sensitivity and Specificity

This article aimed to study the antigenicity of nucleocapsid proteins (NPs) in six pathogenic phleboviruses and to provide theoretical evidence for the development of serological diagnostic reagents. NPs of six pathogenic phleboviruses were expressed and purified using a prokaryotic expression system and rabbits were immunized with individual recombinant NPs. Cross-reactions among NPs and rabbit sera were determined by both indirect ELISA and Western blotting analyses, and the sera titer was determined by indirect ELISA. Furthermore, sera from SFTS patients were also detected by each recombinant NP as a coating antigen using indirect ELISA. The cross-reactions and the sera titer were subsequently determined. Both the concentration and purity of recombinant NPs of six pathogenic phleboviruses met the standards for immunization and detection. The results of indirect ELISA and Western blotting showed that each anti-phlebovirus NP rabbit immune serum had potential serological cross-reactivity with the other five virus NP antigens. Furthermore, the sera from SFTS patients also had cross-reactivity with the other five NP antigens to a certain extent. Our preliminary study evaluated the antigenicity and immune reactivity of six pathogenic phleboviruses NPs and laid the foundation for the development of diagnostic reagents.
Animals ; Antibodies, Viral ; immunology ; Antigens, Viral ; genetics ; immunology ; Cross Reactions ; Humans ; Nucleocapsid Proteins ; genetics ; immunology ; Phlebotomus Fever ; diagnosis ; immunology ; virology ; Phlebovirus ; classification ; genetics ; immunology ; isolation & purification ; Rabbits

Antigens, Bacterial ; immunology ; Antigens, Surface ; immunology ; China ; epidemiology ; Diarrhea ; microbiology ; Escherichia coli Infections ; epidemiology ; microbiology ; Escherichia coli O157 ; classification ; immunology ; isolation & purification ; Humans

House dust mites produce inhalant allergens of importance to allergic patients. We measured the major group 1 allergens, Der p 1 and Der f 1, from the house dust mites Dermatophagoides pteronyssinus and Dermatophagoides farina, respectively in 100 randomly selected domestic homes from Cheonan, Korea. Dust samples were collected by vacuuming from the living room floor and 1 mattress in each home. Der p 1 and Der f 1 were measured by double monoclonal ELISA. Der p 1 levels were very low, with geometric mean levels for floors and mattresses being 0.11 microgram/g (range: 0.01-4.05) and 0.14 microgram/g (range: 0.01-30.0), respectively. Corresponding levels of Der f 1 were higher, 7.46 microgram/g (range: 0.01-262.9) and 10.2 microgram/g (range: 0.01-230.9) for floors and mattresses, respectively. D. farinae appears to be the dominant house dust mite in Cheonan.
Animals ; Antigens, Dermatophagoides/immunology/*isolation & purification ; Bedding and Linens ; Dust/analysis ; Floors and Floorcoverings ; Housing ; Humans ; Korea ; Pyroglyphidae/*immunology

OBJECTIVETo investigate the virulence characteristics of two fixed strains (CTN and aG) and a street strain (HN10) of rabies viruses isolated in China.

METHODSICR mice of different age groups were inoculated with CTN, aG and HN10 rabies virus strains via the intracracerebral (i.c.) or intramuscular (i.m.) routes, and observed for 20 days.

RESULTSThe CTN strain was pathogenic to 7-day-old suckling mice that received i.c. inoculations and 3-day-old suckling mice that received i.m. inoculations. The aG strain was pathogenic to 4-week-old mice that received i.c. inoculations and 7-day-old suckling mice that received i.m. inoculations. The HN10 strain was pathogenic to mice of all age groups via both inoculation routes. In moribund mice, the viruses had spread to most regions of the brain. The CTN and HN10 strains had similar dissemination patterns in the brain; both viral antigens could be found in the dentate gyrus (DG), whereas few viral antigens were present in the DG from specimens that had been infected with the aG strain.

CONCLUSIONA comprehensive sequence analysis of the G protein suggested that differences in gene sequences may be responsible for producing strain-specific differences in pathogenicity and distribution in the brain.

Animals ; Antigens, Viral ; immunology ; Brain ; immunology ; virology ; China ; Mice ; Mice, Inbred ICR ; Nucleocapsid Proteins ; immunology ; Rabies ; virology ; Rabies virus ; immunology ; isolation & purification ; pathogenicity

OBJECTIVEThrough detecting the standard preparation with series of concentration to indirectly calculate the anti-HBs concentration of the serum samples, a suitable anti-HBs quantitative method for our laboratory was found after comparing the two kinds of methods.

METHODSDetecting the anti-HBs standard preparation with series of concentration by RIA method, standard curvilinear equations were obtained by the means of fitting the detected result and the corresponding concentration by log-log model and exponential curve model respectively. Then the fitting efficiency of two curves was compared. By calculating the concentrations of the reference using two standard curvilinear equations, we can compare the accuracy of two quantitative methods.

RESULTThe error mean square of the exponential curve model is low as 1.2971 and the determinate coefficient is close to 1 with the value of 0.9904. The average concentrations (n=6) of the detected reference calculated by two curvilinear equation with the actual concentration of 30.0 mIU/mL are (32.28 +/- 1.06) and (31.91 +/- 1.06) mIU/ mL respectively. The concentration calculated by exponential curve model is only 6.37% higher than the actual concentration.

CONCLUSIONFitting by exponential curve model is more practical to estimate the actual concentration of the serum samples those will be detected. It can be used as an optimal quantitative method to detect anti-HBs concentration.

Hepatitis B ; blood ; immunology ; virology ; Hepatitis B Antibodies ; blood ; immunology ; Hepatitis B Surface Antigens ; blood ; immunology ; Hepatitis B virus ; immunology ; isolation & purification ; Humans ; Male ; Radioimmunoassay ; methods

OBJECTIVETo prepare eukaryotic expression of rotavirus (RV) SA11 capsid protein VP7, and to generate and purify yolk immunoglobulin (IgY) antibodies against the recombinant VP7 from Roman hens.

METHODSMA104 cells were infected with the standard SA11 strain and the culture fluid was collected. A DNA fragment of 978 bp encoding SA11 VP7 was obtained by RT-PCR amplification from genomic RNA of RV SA11. The PCR products were ligated to pMD18-T vector following the confirmation by DNA sequencing and sub-cloned into pPICZalphaB. The recombinant pPICZalphaB-SA11 VP7 was transformed into E coli Top10. The plasmids were linearized by digestion of BstXI and transformed into Pichia pastoris X-33 through electroporation by DNA sequencing. The transformants were induced with methanol for expression. The cultural supernatant was subjected to SDS-PAGE and Western blotting. Fusion expression was purified through the column of affinity chromatography. IgY was identified and purified by SDS-PAGE and Western blotting from eggs of Roman hens immunized with recombinant SA11 VP7.

RESULTSThe RNA extracted from the RV culture fluid consisted of 11 bands visualized by silver staining. The expression vector pPICZalphaB-SA11 VP7 was constructed and the fusion protein in Pichia pastoris X-33 was harvested and purified. The recombinant SA11 VP7 with molecular weight of 40 200 was identified by Western blotting. The IgY antibodies against the recombinant SA11 VP7 were produced with a purity of 95 percent and yield of 10.2 mg per egg.

CONCLUSIONThe preparation of IgY antibodies to recombinant SA11 VP7 might lay a foundation for the development of vaccines and diagnostic techniques.

Animals ; Antigens, Viral ; genetics ; immunology ; metabolism ; Capsid Proteins ; genetics ; immunology ; metabolism ; Chickens ; Cloning, Molecular ; Immunoglobulins ; immunology ; isolation & purification ; Recombinant Proteins ; genetics ; immunology ; metabolism