1.Expression of human HZF1 in E. coli and preparation of antibody against human HZF1 protein.
Han PENG ; Xin ZHANG ; Zhan-Wen DU ; Jun-Wu ZHANG
Acta Academiae Medicinae Sinicae 2007;29(6):772-776
OBJECTIVETo express human HZF1 fusion protein in E. coli and to obtain an anti-HZF1 antibody.
METHODSA DNA fragment encoding non-zinc finger region of HZF1 protein was inserted into pET30a vector to get the recombination expression plasmid pET30a-HZF1. E. coli was transformed with pET30a-HZF1 and the selected clones were cultured with isopropy-beta-D-thiogalactoside induction. The proteins were prepared from the culture and the fusion protein was purified by Ni column. Rabbits were immunized and reinforced three times with the purified fusion protein. The antiserum was collected and the titer and the specificity of the antibody were checked by ELISA and Western blot.
RESULTSAntibody against HZF1 was obtained and its titer was more than 1:100 000, as proven by ELISA. Western blot analysis showed specific reaction between this antibody and HZF1 fusion protein or the endogenetic HZF1 protein in hemin-induced K562 cells.
CONCLUSIONSThe specific antibody against HZF1 is obtained. The antibody may have potential application in farther HZF1 function study and HZF1 determination in tissues and cells.
DNA-Binding Proteins ; genetics ; immunology ; metabolism ; Escherichia coli ; genetics ; metabolism ; Gene Transfer Techniques ; Immune Sera ; immunology ; Recombinant Fusion Proteins ; genetics ; immunology ; metabolism ; Transformation, Bacterial
2.Preparation and identification of polyclonal antiserum against angiotensinogen.
Qing-Jun MENG ; Jian LI ; Wen-Hong ZHANG ; Le-Ning ZHANG ; Li-Fan ZHANG
Acta Physiologica Sinica 2003;55(1):110-113
For studying the expression and distribution of angiotensinogen (AGT), the C-teminus of rat AGT gene was expressed in E.coli. Rabbits were immunized with expressed AGT protein and sera from different rabbits were raised. ELISA showed a high titre (1:25600) of the antiserum. With the antiserum, Western blotting recognized not only the prokaryotic expressed AGT, but also the endogenous AGT protein in liver tissue of both rats and humans. Using this antiserum, immunohistochemistry showed the expression of AGT protein in islet cells of human pancreas as well as in epithelium of human bile duct. These results suggest that the prokaryotic expressed AGT protein is an effective immunogen for the preparation of anti-AGT antiserum. Our present work provides an important tool for study of the pathophysiological role of AGT as well as local renin-angiotensin system.
Angiotensinogen
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genetics
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immunology
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Animals
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Antibodies, Monoclonal
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biosynthesis
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Escherichia coli
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genetics
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metabolism
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Humans
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Immune Sera
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biosynthesis
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immunology
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Immunization
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Rabbits
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Rats
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Recombinant Proteins
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biosynthesis
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genetics
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immunology
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Renin-Angiotensin System
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physiology
3.Identification of VP3 antigenic epitopes of infectious bursal disease virus.
Xiao-yun DENG ; Yu-long GAO ; Hong-lei GAO ; Xiao-le QI ; Xiao-yan WANG ; Xiao-mei WANG
Chinese Journal of Virology 2007;23(4):305-311
Infectious bursal disease virus(IBD) causes infectious bursal disease (IBD), which infects bursal of chicken and can evoke immune suppression. This study identified the antigenic epitopes of four McAbs to IBDV VP3(HRB-3F, HRB-7B, HRB-7C and HRB-10E)with pepscan. A set of 17 partially overlapping or consecutive peptides (P1-P17) spanning VP3 were expressed for epitope screening by pepscan. Finally, two antigenic epitopes, 109-119aa and 177-190aa of IBDV VP3, were identified by Western blot and ELISA. The peptides on epitopes could react with IBDV, and they had better immunnogenicity. The sequences of epitopes were compared with that of several other IBDV strains in the same region, and was found they were totally homologous. This study showed the two epitopes were novel conserved linear B cell epitopes on the VP3 of IBDV. This study provides basis for the development of immunity-based prophylactic, therapeutic and diagnostic measures for control of IBD and further for structural and functional analysis of IBDV.
Animals
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Antibodies, Monoclonal
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immunology
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Antibodies, Viral
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blood
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immunology
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Blotting, Western
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Capsid Proteins
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genetics
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immunology
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metabolism
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Enzyme-Linked Immunosorbent Assay
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Epitopes
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genetics
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immunology
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metabolism
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Immune Sera
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immunology
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Immunization
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Immunohistochemistry
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Infectious bursal disease virus
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genetics
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immunology
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metabolism
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Mice
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Mice, Inbred BALB C
4.Prokaryotic expression and antigenic activity analysis on the matrix protein genes of two strains of human metapneumovirus recently identified in Beijing.
Shou-Chun CAO ; Yuan QIAN ; Guo-Hua LI ; Ru-Nan ZHU ; Lin-Qing ZHAO ; Ya-Xin DING
Chinese Journal of Virology 2007;23(1):60-62
Human metapneumovirus (hMPV) is a recently identified respiratory virus more like human respiratory syncytial virus in clinical symptoms. Matrix protein (M) is one of the most important structural proteins. For further studying of hMPV, the full length of M genes from the recombinant plasmid pUCm-M1816 and pUCmM1817 were cloned by PCR and sub-cloned into the pET30a(+) vector, which is a prokaryotic expression vector, after dual-enzyme digestion with Bam HI and Xho I. The positive recombinated plasmids were transformed into E. coli BL21 (DE3) and expressed under the inducing of IPTG. Target proteins were characterized by SDS-PAGE and Western blotting. In this article, we' ve successfully constructed the recombinated plasmids pET30a-M1816 and pET30a-M1817 which have correct open reading frames confirmed by dual-enzyme digestion analysis and sequencing. The fusion proteins with 6 x His-N were highly produced after inducing by 1mmol/ L IPTG at 37 degrees C. A unique protein band with approximate 27.6 kD was characterized by SDS-PAGE. Most of the target protein existed in inclusion body. Western blot analysis showed that the target protein has specific binding reaction to rabbit antiserum against polypeptides of the matrix protein of hMPV. So the M genes were highly expressed in the prokaryotic system and the expressed M proteins have specific antigenic activities. It can be used for further studying of hMPV infections in Beijing.
Animals
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Antigens, Viral
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genetics
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immunology
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metabolism
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Blotting, Western
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China
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Gene Expression
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Genetic Vectors
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genetics
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Humans
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Immune Sera
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immunology
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Metapneumovirus
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genetics
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immunology
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metabolism
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Plasmids
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genetics
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Prokaryotic Cells
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metabolism
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Rabbits
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Species Specificity
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Viral Structural Proteins
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genetics
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immunology
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metabolism
5.A Novel Polyclonal Antiserum against Toxoplasma gondii Sodium Hydrogen Exchanger 1.
Bin XIAO ; Zhenzhan KUANG ; Yanli ZHAN ; Daxiang CHEN ; Yang GAO ; Ming LI ; Shuhong LUO ; Wenbo HAO
The Korean Journal of Parasitology 2016;54(1):21-29
The sodium hydrogen exchanger 1 (NHE1), which functions in maintaining the ratio of Na+ and H+ ions, is widely distributed in cell plasma membranes. It plays a prominent role in pH balancing, cell proliferation, differentiation, adhesion, and migration. However, its exact subcellular location and biological functions in Toxoplasma gondii are largely unclear. In this study, we cloned the C-terminal sequence of T. gondii NHE1 (TgNHE1) incorporating the C-terminal peptide of NHE1 (C-NHE1) into the pGEX4T-1 expression plasmid. The peptide sequence was predicted to have good antigenicity based on the information obtained from an immune epitope database. After induction of heterologous gene expression with isopropyl-b-D-thiogalactoside, the recombinant C-NHE1 protein successfully expressed in a soluble form was purified by glutathione sepharose beads as an immunogen for production of a rabbit polyclonal antiserum. The specificity of this antiserum was confirmed by western blotting and immunofluorescence. The antiserum could reduce T. gondii invasion into host cells, indicated by the decreased TgNHE1 expression in T. gondii parasites that were pre-incubated with antiserum in the process of cell entry. Furthermore, the antiserum reduced the virulence of T. gondii parasites to host cells in vitro, possibly by blocking the release of Ca2+. In this regard, this antiserum has potential to be a valuable tool for further studies of TgNHE1.
Animals
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Cell Line
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Immune Sera/genetics/immunology/*metabolism
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Male
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Mice
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Protozoan Proteins/genetics/*metabolism
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Rabbits
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Recombinant Proteins/immunology
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Sheep
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Sodium-Hydrogen Antiporter/genetics/immunology/*metabolism
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Toxoplasma/genetics/immunology/*metabolism
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Toxoplasmosis/parasitology/prevention & control
6.Prokaryotic expression, purification of human LINGO-1(aa76-319) and preparation of its polyclonal antibody.
Jun LV ; Xin LU ; Xiao-Dan JIANG ; Chang-Chen HU ; Ying-Qian CAI ; Mou-Xuan DU ; Yu-Xi ZOU ; Ling-Sha QIN
Journal of Southern Medical University 2009;29(11):2175-2178
OBJECTIVETo express and purify the fusion protein of extracellular domain of human Ig domain-containing, neurite outgrowth inhibitor (Nogo) receptor-interacting protein-1 (LINGO-1(aa76-319)) in prokaryotic cells and prepare the rabbit anti-LINGO-1 polyclonal antibody (pAb).
METHODSThe 732 bp DNA sequence of hLINGO-1(aa76-319) was obtained from pCMV-SPORT6 by PCR and inserted into pET30a(+) plasmid to construct the prokaryotic expression plasmid pET30a(+)-hLINGO-1(aa76-319), which was subsequently transformed into E.coli. The target fusion protein was expressed with IPTG induction and purified by Ni(2+)-NTA affinity chromatography column. The antiserum against hLINGO-1(aa76-319) was obtained from the rabbits immunized with hLINGO-1(aa76-319), and the titer of the pAb was determined using enzyme linked immunosorbent assay (ELISA) and its specificity identified using Western blotting.
RESULTSThe prokaryotic expression plasmid pET30a(+)-hLINGO-1(aa76-319) was constructed successfully. Efficient expression of the target fusion protein was achieved with IPTG induction at the optimal concentration of 0.4 mmol/L and culture temperature at 37 degrees celsius; for 2.5 h. The hLINGO-1(aa76-319) fusion protein was effectively expressed in E.coli as inclusion bodies, and the soluble protein was obtained through denaturation and refolding procedures, and the purified fusion protein showed a purity above 90%. The titer of the anti-hLINGO-1(aa76-319) pAb obtained by immunizing the rabbits with the purified protein reached 1:1.6x10(6), and Western blotting confirmed its good specificity.
CONCLUSIONThe fusion protein hLINGO-1(aa76-319) with high purity has been obtained and the anti-hLINGO-1(aa76-319) pAb obtained shows a high titer and good specificity, which provide important experimental basis for further functional investigation of LINGO-1.
Animals ; Antibodies ; immunology ; isolation & purification ; Antibody Specificity ; Escherichia coli ; genetics ; metabolism ; Humans ; Immune Sera ; immunology ; Membrane Proteins ; biosynthesis ; genetics ; immunology ; Nerve Tissue Proteins ; biosynthesis ; genetics ; immunology ; Plasmids ; genetics ; Rabbits ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; immunology
7.Human CD96 gene cloning, expression and identification.
Jian-ming ZENG ; Fei LIU ; Ping-hai TAN ; Li-na WANG ; Mo LI ; Zhong-hua CHEN ; Song LI ; Yi-fei LONG ; You-qiang LI ; Cha CHEN
Journal of Southern Medical University 2011;31(7):1232-1235
OBJECTIVETo construct and express human CD96 gene outer membrane domain (hCD96om) in prokaryotic cells and prepare rabbit polyclonal antibody of hCD96om.
METHODShCD96om was amplified by RT-PCR from the peripheral blood of patients with acute myeloid leukemia and inserted into prokaryotic expression vector pET32a(+) to construct the recombinant plasmid pET32-CD96. The expression of hCD96om was induced by IPTG in BL21(DE3) cells, and the expression product was identified by Western blotting. The anti-hCD96 polyclonal antibody was prepared by immunization of rabbits with the fusion protein. The specificity of anti-hCD96 antibody was determined by Western blotting.
RESULTShCD96om protein was expressed in E.coli BL21(DE3) cells in the form of inclusion body, with a relative molecular mass around 37 kD. Western blotting showed a specific reaction of the prepared antiserum with the 70 kD protein extracted from human leukemia cell line HL-60 cells and with the 37 kD hCD96om fusion protein.
CONCLUSIONThe CD96 gene of human has been successfully cloned and expressed in BL21(DE3) cells, and its rabbit polyclonal antibody has been obtained.
Animals ; Antibodies ; immunology ; metabolism ; Antigens, CD ; biosynthesis ; genetics ; immunology ; Base Sequence ; Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Humans ; Immune Sera ; biosynthesis ; Immunization ; Leukemia, Myeloid, Acute ; immunology ; Molecular Sequence Data ; Neoplastic Stem Cells ; immunology ; Rabbits ; Recombinant Proteins ; biosynthesis ; genetics ; immunology
8.Expression, antiserum preparation and bioactivity assays of insect neurotoxin LqhIT2.
Chinese Journal of Biotechnology 2008;24(10):1761-1767
According to the codon bias of Pichia pastoris, the mature insect neurotoxin gene LqhIT2 was synthesized based on its amino acid sequence and was cloned to vector of PET-30a (+) and pPIC9K respectively. The fusion protein expressed in Escherichia. coli was induced with IPTG and purified with Ni-NTA His Bind Column. The purified fusion protein was used to immunize BALB/c mice, and antiserum obtained was highly specific with the titer of over 1:128 000. Using the antiserum, high-level expression transformants of P. pastoris were screened by dot blotting. The highest expression of recombinant LqhIT2 was about 9 mg/L in baffled flasks. The fusion protein of LqhIT2 expressed in E. coli was not toxic to locust, but the recombinant LqhIT2 expressed in P. pastoris had insecticidal activity against locust through injection.
Animals
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Escherichia coli
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genetics
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metabolism
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Immune Sera
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biosynthesis
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Immunization
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Mice
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Mice, Inbred BALB C
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Neurotoxins
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biosynthesis
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genetics
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immunology
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Pichia
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genetics
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metabolism
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Recombinant Fusion Proteins
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biosynthesis
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genetics
;
immunology
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Scorpion Venoms
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biosynthesis
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genetics
;
immunology
9.Cloning and expression of Chlamydia trachomatis OmcBc gene and antigenicity analysis of the protein.
Jie WANG ; Ying-qian ZHANG ; Guang-ming ZHONG ; Ping YU
Journal of Southern Medical University 2010;30(7):1558-1561
OBJECTIVETo investigate the antigenicity of recombinant Chlamydia trachomatis (Ct) OmcBc protein and search for the new target for early diagnosis of Chlamydia infection and Chlamydia vaccine development.
METHODSThe C fragment of OmcB encoding the amino acids from T270 to T553 was amplified from Chlamydia serovar D genomic DNA. The pGEX-6p-Ct OmcBc expression plasmid was constructed and transformed into E.coli XL-1blue. The expression of recombinant Ct OmcBc protein was induced by IPTG. Serum samples were collected from 120 patients with urogenital Chlamydia infection. The antiserum samples were collected from 7 New Zealand white rabbits and 5 Balb/C mice immunized subcutaneously and intraperitoneally with Ct serovar D inactivated EB, respectively, and from 9 Balb/C mice intranasally infected with Ct serovar D live EB. The anti-Chlamydia specific antibody were titrated by an immunofluorescence assay (IFA). The reactivity of the recombinant OmcBc protein with all the above antisera was detected by ELISA.
RESULTSThe pGEX-6p-Ct OmcBc expression plasmid was successfully constructed. DNA sequencing showed that the inserted OmcBc was about 852 bp, encoding a protein with 284 amino acids. The expression of the recombinant GST-OmcBc was induced by IPTG, producing a fusion protein with a molecular weight of about 57 kD. The titer of the specific antibodies to Chlamydia in all the antisera was high. ELISA results showed strong reactivities of the recombinant GST-OmcBc fusion protein with all the above antisera.
CONCLUSIONSOmcBc protein is an immunodominant protein of Chlamydia. The recombinant GST-OmcBc with strong antigenicity may provide a basis for further study of early diagnosis of chlamydia infection and development of Chlamydia vaccine.
Animals ; Antibodies, Bacterial ; blood ; Antigens, Bacterial ; immunology ; metabolism ; Bacterial Outer Membrane Proteins ; genetics ; immunology ; Chlamydia trachomatis ; genetics ; immunology ; metabolism ; Cloning, Molecular ; Genes, Bacterial ; Humans ; Immune Sera ; immunology ; Mice ; Mice, Inbred BALB C ; Plasmids ; Rabbits
10.Reconstruction of Leptospira interrogans lipL21 gene and characteristics of its expression product.
Dong-jiao LUO ; Ye HU ; R H DENNIN ; Jie YAN
Journal of Zhejiang University. Medical sciences 2007;36(5):458-464
OBJECTIVETo reconstruct the nucleotide sequence of Leptospira interrogans lipL21 gene for increasing the output of prokaryotic expression and to understand the changes on immunogenicity of the expression products before and after reconstruction, and to determine the position of envelope lipoprotein LipL21 on the surface of leptospiral body.
METHODSAccording to the preferred codons of E.coli, the nucleotide sequence of lipL21 gene was designed and synthesized, and then its prokaryotic expression system was constructed. By using SDS-PAGE plus BioRad agarose image analysor, the expression level changes of lipL21 genes before and after reconstruction were measured. A Western blot assay using rabbit anti-TR/Patoc I serum as the first antibody was performed to identify the immunoreactivity of the two target recombinant proteins rLipL21s before and after reconstruction. The changes of cross agglutination titers of antisera against two rLipL21s before and after reconstruction to the different leptospiral serogroups were demonstrated using microscope agglutination test (MAT). Immuno-electronmicroscopy was applied to confirm the location of LipL21s.
RESULTThe expression outputs of original and reconstructed lipL21 genes were 8.5 % and 46.5 % of the total bacterial proteins, respectively. Both the two rLipL21s could take place immune conjugation reaction with TR/Patoc I antiserum. After immunization with each of the two rLipL21s in rabbits, the animals could produce specific antibody. Similar MAT titers with 1:80 - 1:320 of the two antisera against rLipL21s were present. LipL21 was confirmed to locate on the surface of leptospiral envelope.
CONCLUSIONLipL21 is a superficial antigen of Leptospira interrogans. The expression output of the reconstructed lipL21 gene is remarkably increased. The expression rLipL21 maintains fine antigenicity and immunoreactivity and its antibody still shows an extensive cross immunoagglutination activity. The high expression of the reconstructed lipL21 gene will offer a favorable condition to use its product for further developing a novel universal vaccine as well as detection kit of leptospirosis.
Amino Acid Sequence ; Animals ; Antigens, Bacterial ; genetics ; immunology ; metabolism ; Bacterial Outer Membrane Proteins ; genetics ; immunology ; metabolism ; Bacterial Vaccines ; immunology ; Base Sequence ; Blotting, Western ; Cloning, Molecular ; Electrophoresis, Polyacrylamide Gel ; Escherichia coli ; genetics ; Immune Sera ; immunology ; Leptospira interrogans ; genetics ; immunology ; ultrastructure ; Lipoproteins ; genetics ; immunology ; metabolism ; Microscopy, Immunoelectron ; Molecular Sequence Data ; Rabbits ; Recombinant Fusion Proteins ; genetics ; immunology ; metabolism ; Sequence Analysis, DNA ; Vaccines, DNA ; immunology