Elevated DLL3 in stomach cancer by tumor-associated macrophages enhances cancer-cell proliferation and cytokine secretion of macrophages.

Background: The notch signal pathway is important in the development of both tumor-associated macrophages (TAMs) and stomach cancer, but how Notch signaling affects TAMs in stomach cancer is barely understood.

Methods: The expressions of Notch1, Notch2, Notch3, Notch4, hes family bHLH transcription factor 1 (Hes1), and delta-like canonical Notch ligand 3 (DLL3) were detected by Western blot and the expressions of interleukin (IL)-10, IL-12, and IL1-β were detected using enzyme-linked immunosorbent assay after the co-culture of macrophages and stomach-cancer cells. The proliferation and migration of cancer cells were detected using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and scratch assay, respectively, and the cell cycle was detected using Annexin V/propidium iodide assay.

Production of mouse monoclonal antibodies against Helicobacter pylori Catalase and mapping the antigenic epitope by phage display library.

The Catalase of Helicobacter pylori (H. pylori) helps bacteria to protect themselves from oxygen toxicity and damage and have been identified an immunodominant antigen. To obtain mouse monoclonal antibodies (mAbs) against Catalase and to map its antigenic epitope is potentially to develop a vaccine for prevention and treatment of H.

Production of mouse monoclonal antibodies against Helicobacter pylori Lpp20 and mapping the antigenic epitope by phage display library.

Lpp20, an outer membrane protein of Helicobacter pylori (H. pylori), has been identified as an immunodominant antigen. To obtain mouse monoclonal antibodies (mAbs) against it and to map its antigenic epitope is potentially to develop a vaccine for prevention and treatment of H.

[Cloning, expression and identification of catalase of Helicobacter pylori].

Aim: To construct the recombinant plasmid containing catalase (KatA) of Helicobacter pylori (Hp), analyze its nucleic acid sequence, express it in E. coli and study its antigenicity.

Methods: KatA fragments were amplified from Hp chromosomal DNA by PCR.

[Preparation and identification of monoclonal antibodies against Helicobacter pylori].

Objective: To prepare and identify monoclonal antibodies (mAbs) against Helicobacter pylori (Hp).

Methods: BALB/c mice were immunized with the supernatant and precipitation of cultured Hp after ultrasonication and mAbs were obtained by means of hybridoma technique. The resultant mAbs was evaluated for subtype, titer, affinity, and further identified with Lpp20, HspA, urease A, CagA, urease B, and catalase prepared by recombinant expression.

[Preparation of a monoclonal antibodies against Plasmodium falciparum glutamate dehydrogenase and establishment of colloidal gold-immunochromatographic assay].

Objective: To prepare a monoclonal antibodies (mAbs) against glutamate dehydrogenase (GDH) of Plasmodium falciparum (FCC1/HN strain) and establish colloidal gold-immunochromatographic assay (GICA) for diagnosis of Plasmodium falciparum malaria.

Methods: Recombinant GDH was used to immunize Balb/C mice and the mAbs against GDH were prepared using hybridoma technique followed by identification of IgG isotype and its affinity. Protein-G affinity chromatography was employed to purify the antibodies, which were labeled with colloidal gold for establishment of GICA for Plasmodium falciparum detection.

[Preparation of monoclonal antibodies against multiple antigens].

Objective: To prepare monoclonal antibodies (mAbs) against multiple antigens by single cell fusion.

Methods: BALB/c mice were immunized with the multiple antigens, namely alpha fetoprotein (AFP), carcinoembryonic antigen (CEA), HBsAgiHBcAg and HBeAg, and hybridomas were employed using PEG as the fusing agent. The hybridoma cells were respectively screened with AFP, CEA, HBsAg, HBcAg and HBeAg by enzyme-linked immunosorbent assay and limited dilution.

[Role of intron and 5' untranslated region in human thrombopoietin gene expression].

Objective: To study the role of 5' untranslated region (UTR) and intron in the expression of human thrombopoietin (TPO) gene.

Methods: A number of expression vectors containing TPO mini-gene fused to the regulatory elements of cytomegalovirus (CMV) were constructed and transfected via lipofectin into cultured cos-1 cells for transient expression of TPO gene. The cell culture media were analyzed with highly sensitive sandwich enzyme-linked immunosorbent assay (ELISA) 48 h after the transfection.

[Soluble expression of Plasmodium falciparum glutamate dehydrogenase in Escherichia coli, and its purification and identification].

Objective: To make soluble expression of Plasmodium falciparum (FCC1/HN) glutamate dehydrogenase (GDH) in Escherichia coli, purification and immunocompetence identification of the recombinant non-fusion GDH.

Methods: The GDH gene was cloned into prokaryotic expression vector pET23 (a) to form recombinant expression vector pET23 (a)/GDH. pET23(a)/GDH was transformed into E.

[Refolding and purification of Plasmodium falciparum glutamate dehydrogenase fusion protein].

Objective: To establish the method for renaturation and purification of the fusion protein of Plasmodium falfiparum (FCC1/HN ) glutamate dehydrogenase (GDH) with glutathione S-transferase (GST).

Methods: The recombinant plasmid GDH/pGEX-4T-1, encoding the full-length GDH gene, was transformed into E.coli BL21 (DE3) to achieve IPTG-induced high expression of GDH/GST in the form of inclusion bodies identified by SDS-PAGE.

Cloning and sequence analysis of cDNA and genomic DNA of human thrombopoietin gene.

OBJECTIVE: To study the role of thrombopoietin (TPO) gene 5' untranslated region (UTR) and the intron in TPO expression regulation. METHODS: With the mRNA derived from Chinese human fetal liver as the template, full-length TPO cDNA (approximately 1.1 kb) and TPO genomic DNA(6.

[Construction of the recombinant plasmid FasAD-pTYB2 capable of Fas activation domain fusion expression].

Objective: To construct the recombinant plasmid FasAD-pTYB2 for the fusion expression of Fas activation domain (FasAD).

Methods: FasAD cDNA was cloned by semi-nested reverse transcriptase-polymerase chain reaction (RT-PCR), and then inserted into the universal vector of pGEM-T for the identification of its DNA sequence. The target DNA fragment was inserted into the prokaryote vector pTYB2 that expressed intein to construct the plasmid recombinant FasAD-pTYB2 which was induced by isopropylthio-beta-D-galactoside for the expression of the fusion protein.