Objective To explore the efficacy and protective mechanism of calpain, a calcium activated neutral proteinase as a vaccine candidate molecule. Methods Anti calpain sera were prepared by immunized BALB/c mice with recombinant calpain. Anti calpain sera, schistosomula of Schistosoma japonicum , and mouse eosinophils were incubated at 37 ?C , 5% CO 2 for 48 hours, and the adherence of eosinophils to schistosomula and its schistosomulacidal efficacy were observed. Results Mice immunized with recombinant calpain produced a high level IgG antibodies specific to the antigen immunized. Immunoblotting analysis showed murine anti recombinant calpain sera bound specifically to recombinant calpain. Ninety six percent of schistosomula were surrounded by cells when incubated with mouse eosinophils, and a significant number of dead schistosomula was observed at 48 hours when incubated with mouse serum and eosinophils as compared with control serum and eosinophils ( P

Objective To investigate the efficacy of sophocarpine in rats with alcoholic liver disease and its effects on the expression of tumor necrosis factor (TNF)-α,interleukin (IL)-6 and transforming growth factor (TGF)-β1.Methods A total of 48 male Sprague-Dawley adult rats were evenly divided into healthy control group,model group,prevention group and treatment group.The rats in the healthy control group were gavaged with 0.9％NaCl every day for 12 weeks.The rats in the model group,prevention group and treatment group were gavaged with alcohol for 12 weeks to establish the model.The prevention group was injected with 20 mg · kg1 · d1 sophocarpine for 12 weeks.Since the fifth week,the treatment group was continuously injected with 20 mg · kg1 · d-1 sophocarpine for eight weeks.The histological changes were evaluated.The serum levels of alanine aminotransferase (ALT), aspartate aminotransferase ( AST ), alkaline phosphatase (AKP),triglyceride (TG) and total cholesterol (TC) were examined.And the expression of TNF-α,IL-6 and TGF-β1 in liver tissue at mRNA and protein level were detected with immunohistochemistry and real-time polymerase chain reaction (PCR) assay.Comparison among groups was perform with single factor analysis of variance,pairwise comparisons with least significant difference method (LSD method),ranked data with Kruskal-Wallis H-test and multiple pairwise comparison with Nemenyi test.Results Compared with model group,hepatic steatosis and inflammatory cell infiltration were significantly improved in the treatment group and prevention group.The levels of ALT (41.40 U/L± 10.53 U/L and 40.75 U/L±6.94 U/L vs 58.37 U/I±5.35 U/L),AST(121.60 U/L±16.24 U/L and 109.50 U/L±9.23 U/L vs 156.63 U/L±32.47 U/L),AKP(114.88 U/L±40.37 U/L and 112.60 U/L±44.34 U/L vs 161.75 U/L±28.95 U/L),TG (4.19 mmol/L±0.99 mmol/L and 2.69 mmol/L± 1.35 mmol/L vs 4.50 mmol/L±0.99 mmol/L) and TC (1.48 mmol/L±0.28 mmol/L and 1.43 mmol/L±0.19 mmol/L vs 1.67 mmol/L±0.20 mmol/L) significantly decreased and the difference was statistically significant ( all P＜0.05).The expression of TNF-α,IL-6 and TGF-β1 at mRNA and protein level in liver tissue of model group were significantly higher than those of healthy control group,prevention group and treatment group.After treated with sophocarpine,the expression of TNF-α(mRNA:1.36 ± 0.08,1.16 ± 0.05 ; protein:3.38 ％ ± 0.82 ％,1.74 ％ ± 0.65 ％ ),IL-6 (mRNA:1.51 ± 0.05,1.39 ± 0.02; protein:5.89％ ± 0.96％,4.26％ ± 0.53％) and TGF-β1 (mRNA:1.39±0.04,1.37±0.02; protein:4.27％ ±0.97％,2.11％ ±0.83％) of treatment group and prevention group at mRNA and protein level significantly lower than those of model group (mRNA:1.81±0.16,1.95 ±0.13,1.84±0.22; protein:5.82％ ± 1.21％,7.63％ ±1.03％,5.33％± 1.12％) and the difference was statistically significant (all P＜0.01).Conclusion Sophocarpine significantly alleviates alcohol induced liver injury in rats,improves liver steatosis and inflammatory reaction degree,which may be related with the downregulation of TNF-α,TGF-β1 and IL-6 expression in liver tissue of ALD rats.

Objective Rab11 GTPases play an essential role in regulating membrane trafficking pathways in eukaryotic cells. Nonetheless, there has been little work done on characterizing the transport machinery of Trichomonas. The aim of this study is to clone and characterize a Rab11 gene of Trichomonas vaginalis.Methods A cDNA expression library was constructed with T. vaginalis total RNA. A cDNA clone, which showed a high degree of homology with Rab proteins of different species, was isolated and sequenced. Sequence analysis was performed using BLASTP, RPS-BLAST and ClustalW programs. The genomic DNA corresponding to the cDNA sequence was amplified using PCR techniques and following by sequencing. Results cDNA with a length of 710 base pairs and an open reading frame of 636 bp was obtained. The deduced amino acid sequence from the open reading frame was found to possess 211 residuals. Sequence analysis demonstrated that this cDNA clone was homologous to the Rab11 subfamily of different species (60% identity and 79% similarity with Arabidopsis thaliana Rab11c, 58% identity and 78% similarity with human Rab11b), and that the amino acid sequence contains all the well known conserved sequence elements of Rab family. Specific Rab motifs were also detected in the deduced amino acid sequence. Phylogenetic analysis showed that its closest homologues are Rab11 proteins from other species. Sequencing of the PCR product of genomic DNA revealed that the genomic DNA sequence encompassing the putative 5'-ATG and 3'-stop codon is identical to the cDNA sequence.Conclusion A cDNA clone corresponding to the T. vaginalis Rab11 gene was obtained.The function of this gene in regulating membrane trafficking pathways of the parasitic protist is still under investigation.

To identify the gene differentially expressed in female Anopheles anthropophagus and to analyze its gene sequence, this gene amplified by PCR was identified by real-time PCR and its cDNA was then amplified with rapid amplification of cDNA ends (RACE) technology. It was found that the expression ratio of the female differentially expressed gene in female and male mosquitoes was 267.49 according to the formula F=2~(-⊿⊿CT).The size of mRNA of the gene was 364 bp, and the amino acid sequence deduced from the open reading frame (ORF) was found to be similar to the sequence of tectin protein of Culex quinquefasciatus and proteins of other species. The mRNA sequence of this gene was submitted to NCBI with a accession number of FJ907236. This gene may provide a foundation for further studies on the biological functions of mosquitoes.

Objective To detect infection of Angiostrongylus cantonensis and examine effection of treatment to prepare monoclonal antibodies(McAbs). Methods Six-week-old BALB/c mice were imrnunized by the intraperitoneal injection of e/s antigens of Angiostrongylus cantonensis. Fusion of splecn cells from immunized mice with prepared SP2/0-Ag14 myeloma cells was performed in RPMI 1640. Fused cells were suspended in RPMI 1640 containing 1% HAT and 20% fetal calf serum and dispensed into 96-well cell culture plates. The supernatants of clones were screened by ELISA with sera of patients of angiostrongyliasis.Distribution of cohere antigen of 12D5 and 21B7 monoclonal antibodies was analyzed with immunohistochemistry. Two McAbs ( 12D5 and 21B7) were applied to detect the circulating antigen (CAg) in the sera of rats infected with A. cantonensis and angiostrongyliasis patients respectively by double antibody sandwich ELISA.Results 12D5 McAb was identified as IgG1 and 21 B7 McAb was IgM. Western blot result showed two McAbs could used to identified 55 × 103 protein of adult worms of A. cantonensis. Cohere antigen of 12D5 and 21B7 monoclonal antibodies were distributed on intestine surface of A. cantonensis. The detection rates of CAg in the sera of infected rats 100% (48/48), the detection rates of CAg in the sera of angiostrongyliasis patients was 100% (32/32). No cross-reaction to sera of patients with other infection of parasites, such as clonochiasis, fasiolopsiasis, ancylostomiasis, trichinosis, anisakiasis as well as schsitosomiasis, and health srea did not reacted with 12D5 and 21B7 McAbs,and detaction rate of antibody of angiostrongyliasis patients only reached 75% (24/32) with antigen of A. cantonensis. Conclusion Cohere antigen of 12D5 and 21B7monoclonal antibodies were antigens of enteric epithelium. Sandwich ELISA with 12D5 and 21B7 McAbs showed high specificity act as detecting CAg of A. cantonensis in sera of infection animal and patients. It is apparent that Sandwich ELISA with 12D5 and 21 B7 is not only rapid and simple without requirement of special instrument, but also rather sensitive and specific for the detection of current infection with A. cantonensis.

To construct a recombinant plasmid Pet23a-M, the gene encoding severe acute respiratory syndrome (SARS) coronavirus membrane protein was amplified by RT-PCR and cloned into the expression plasmid Pet23a. Results of restriction endonuclease analysis, PCR detection and DNA sequencing analysis revealed that the cloned DNA sequence was the same as that reported. The recombinants were transformed into Escherichia coli (E. Coli) BL21 (DE3) and induced by Isopropyl-beta-D-thiogalactopyranoside (IPTG). The expression of 27 kD (1 kD=0.992 1 ku) protein was detected by SDS-PAGE and pured by metal chelated chromatography. Results of Western-blot showed that this expressed protein could react with antibodies in sera of SARS patients during convalescence. This provided the basis for the further study on SARS virus vaccine and diagnostic agents.
Cloning, Molecular ; Escherichia coli/genetics ; Escherichia coli/metabolism ; Membrane Proteins/*biosynthesis ; Membrane Proteins/genetics ; Membrane Proteins/isolation & purification ; Plasmids/biosynthesis ; Plasmids/genetics ; Recombinant Proteins/biosynthesis ; Recombinant Proteins/genetics ; Recombinant Proteins/isolation & purification ; Reverse Transcriptase Polymerase Chain Reaction ; SARS Virus/chemistry ; SARS Virus/*genetics ; Viral Vaccines/biosynthesis

Objective To perform laboratory detection and molecular traceability analysis on a case of imported kala-azar in Shenzhen to determine the infection strain. Methods Bone marrow puncture fluid and blood samples from a case of kala-azar in Shenzhen were collected for laboratory tests. The patient's bone marrow puncture fluid smears were stained with Giemsa and examined under a microscope. Blood samples were examined for antibodies using the rk39 visceral leishmania rapid diagnostic reagent. Whole blood DNA was extracted, and the ITS-1 sequence was amplified by PCR, sequenced and aligned, and a phylogenetic tree was constructed based on the ITS-1 sequence. Results Microscopic examination of the patient's bone marrow smears revealed a large number of Leishmania amastigotes without flagella, confirming the diagnosis of kala-azar. The patient's blood was tested positive with the rk39 rapid diagnostic reagent, and PCR amplification yielded an ITS-1 gene product sequence that matched the expected size. Sequence alignment with the NCBI database showed 100% sequence similarity with the ITS-1 gene sequence of Leishmania infantum, confirming the infecting strain as Leishmania infantum. Phylogenetic tree construction of the amplified ITS-1 sequence revealed clustering into a clade with Leishmania infantum , and close to KC347299, one of the reference sequence selected. Conclusions The case of kala-azar in Shenzhen was caused by Leishmania infantum. Kala-azar still occurs in China, so the diagnostic technology of medical personnel in non-epidemic areas should be strengthened so that they can actively use new diagnostic technologies to assist in diagnosis, thus improving their prevention and control ability of Leishmania parasites.

OBJECTIVETo obtain 1-4 IgG-like domains of mouse vascular endothelial growth factor receptor 2 (VEGFR2) fusion protein (mVEGFR2D1-4/GST) and identify its antiginicity and biological activity.

METHODSThe gene of mVEGFR2D1-4 was amplified by RT-PCR from 14-days embryos of Balb/c mice. The PCR product was cloned into pET-42a prokaryotic expression vector to construct the recombinant plasmid pET-42a-mVEGFR2D1-4, which was transformed into E. coli BL21 (DE3) strain for mVEGFR2D1-4/GST expression. The fusion protein was identified by SDS-PAGE and Western blotting, and the antigenicity of the protein purified by affinity chromatography was characterized by ELISA. The VEGF blocking effect of the purified protein in human umbilical vein endothelial cells (HUVECs) were evaluated in in vitro cell cultures.

RESULTSThe mVEGFR2D1-4 gene was obtained, which had an identical sequence to that retrieved in GenBank. The prokaryotic expression vector for mVEGFR2D1-4 was successfully constructed as confirmed by enzyme digestion and DNA sequencing. Both Western blotting and ELISA demonstrated the antigenicity of the purified mVEGFR2D1-4 fusion protein, which obviously blocked the effect of VEGF in promoting HUVEC proliferation in vitro.

CONCLUSIONThe mVEGFR2D1-4/GST fusion protein obtained shows a strong antigenicity and biological activity to facilitate further study of active anti-tumor immunotherapy targeting VEGFR2.

Animals ; Cell Proliferation ; Escherichia coli ; genetics ; metabolism ; Female ; Gene Expression ; Genetic Vectors ; Human Umbilical Vein Endothelial Cells ; Humans ; Mice ; Mice, Inbred BALB C ; Plasmids ; Recombinant Fusion Proteins ; genetics ; immunology ; isolation & purification ; Reverse Transcriptase Polymerase Chain Reaction ; Vascular Endothelial Growth Factor Receptor-2 ; genetics ; immunology ; isolation & purification

Objective To construct a prokaryotic expression system containing the dense granule protein 4(GRA4) of Toxoplasma gondii,purify the expressed protein and detect its immunogenicity.Methods The specific fragment of GRA4 gene was amplified by PCR.After subcloning the prokaryotic expression recombinant pET,GRA4,the expressed product was purified with His?BindTM affinity chromatography and analyzed by Western blot.BALB/c mice were immunized with the GRA4 recombinant protein,and the antibody IgG titer was detected by ELISA.Results The pET,GRA4 prokaryotic expression system was obtained.The MW of the expressed protein was Mr 40 000 and formed in inclusion body.After purification,the recombinant protein could be specifically recognized by the T.gondii infected rabbit serum.Mice immunized with the purified recombinant protein elicited high titer of IgG antibody.Conclusion The pET,GRA4 recombinant protein was successfully expressed and purified,which shows the immunogenicity.

OBJECTIVETo investigate the influence of electroporation on the immunogenicity of the DNA vaccine pVAX- tG250FcGB.

METHODSThe DNA vaccine pVAX-tG250FcGB was constructed by inserting the coding gene of tG250 fusion genes into the expression vector pVAX. The DNA vaccine was delivered in BALB/c mouse by electroporation or intramuscular injection, and the induced antigen specific immune responses were compared.

RESULTSThe vaccine delivered by electroporation and intramuscular injection both induced immune responses in BALB/c mouse, but electroporation produced an obviously stronger effect than intramuscular injection.

CONCLUSIONElectroporation-mediated DNA vaccine delivery can produce strong immune response in mice and is an effective means for studying the immunogenic effect of DNA vaccine pVAX-tG250FcGB.

Animals ; Antibody Formation ; Antibody Specificity ; Antigens, Neoplasm ; genetics ; immunology ; Electroporation ; Gene Fusion ; Granulocyte-Macrophage Colony-Stimulating Factor ; genetics ; immunology ; HEK293 Cells ; Humans ; Injections, Intramuscular ; Male ; Mice ; Mice, Inbred BALB C ; Plasmids ; Random Allocation ; Recombinant Fusion Proteins ; genetics ; immunology ; Transfection ; Vaccines, DNA ; genetics ; immunology