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.coli BL21(DE3). Induced by IPTG(isopropyl-beta D-thiogalactoside), GDH was highly expressed in the supernatant after sonication. The soluble recombinant GDH was purified by Source-Q and Source-S chromatography. Enzyme-linked immunosorbent assay and Western blotting were carried out to identify the immunocompetence of the purified product. Results SDS-PAGE analysis showed that the soluble GDH protein accounted for approximately 15% of the total bacterial protein. By two-step ion-exchange chromatography, the purity of GDH reached more than 90% and the GDH possessed high antigenicity. Conclusion The soluble expression of GDH results in an integral three-dimensional structure epitope with high biological activity.

Objective:To clone and express human Fas activation domain(FasAD)with the bioactivity.Methods:The FasAD cDNA was amplified by seminested RT PCR,and then inserted into the prokaryote vector of pTYB12 expressed intein protein to construct the recombinant plasmid of FasAD pTYB12.The FasAD peptide was expressed and purified in IMPACT TM CN system by the method of one step affinity purification.Results:Sequence analysis revealed that cloned FasAD cDNA sequence was completely same as that of Genebank record(M67454).Soluble fusion protein was successfully expressed by induction of IPTG.The FasAD peptide with a molecular weight of 5 000 was obtained by purification and was recognized by the rabbit anti human Fas polyclonal antibody in Western blot analysis.It’s activity of inhibition of apoptosis induced by rhFasL can each to 70% in primary biological detection.Conclusion:The above results indicated that FasAD peptide could be prepared by using the IMPACT TM CN system,thus laid a relatively experimental foundation for further research of relationship between structure, function and interaction with it’s ligands,and for further development of biological immune modulator. [

Innate and adaptive immune responses initiated by infection depend on recognition and control of pathogens by macrophages,dendritic cells,T cells and so on.Notch signaling pathway is a highly conserved pathway,which is activated by interac-tion of receptors and ligands,thus coordinating important life processes of cells.At present,it has been confirmed that Notch signaling pathway is involved in development,differentiation,maturation and activation of many kinds of immune cells,and plays an important role in infectious diseases.In this review,we mainly focus on the role of Notch signaling pathway in immune regulation during different pathogens infection and its interaction with other signaling pathways.Additionally,therapeutic methods and challenges of developing Notch signaling as a target in infectious diseases are also discussed.

Objective To construct a eukaryotic expression plasmid carrying human full-length Notch ligand Delta-like 3 (DLL3) gene and study the effect of DLL3 knockdown and overexpression on the proliferation of gastric cancer cells in vitro. Methods Human full-length DLL3 gene was amplified by PCR and cloned into the eukaryotic expression vector pCMV-Tag4. After verification by restriction enzymes and sequencing, the recombinant DLL3/pCMV-Tag4 vector was transiently transfected into HEK293T cells, in which the expressions of human DLL3 mRNA and protein were detected using real-time quantitative PCR and Western blotting, respectively. The expression of DLL3 in normal gastric epithelial cells and gastric cancer cell lines was detected by qRT-PCR and Western blotting. DLL3/pCMV-Tag4 was transfected into 3 gastric cancer cell lines, and their proliferation was assessed with MTT assay. Human gastric cancer cells MGC803 and MKN45 were also transfected with a specific human DLL3-siRNA to assess the effect of DLL3 down-expression on the cell proliferation. Results The recombinant eukaryotic expression vector DLL3/pCMV-Tag4 was successfully constructed and human full-length DLL3 was expressed in HEK293T cells. MTT assay showed that DLL3 over-expression obviously promoted the proliferation and down-regulation of DLL3 inhibited the proliferation of the gastric cancer cells. Conclusion DLL3 overexpression can promote the proliferation of gastric cancer cells in vitro, and down-regulation of DLL3 inhibits the proliferation of gastrc cancer cells,which provides a novel strategy for targeted thrapy of gastric cancer.

Objective To construct a eukaryotic expression plasmid carrying human full-length Notch ligand Delta-like 3 (DLL3) gene and study the effect of DLL3 knockdown and overexpression on the proliferation of gastric cancer cells in vitro. Methods Human full-length DLL3 gene was amplified by PCR and cloned into the eukaryotic expression vector pCMV-Tag4. After verification by restriction enzymes and sequencing, the recombinant DLL3/pCMV-Tag4 vector was transiently transfected into HEK293T cells, in which the expressions of human DLL3 mRNA and protein were detected using real-time quantitative PCR and Western blotting, respectively. The expression of DLL3 in normal gastric epithelial cells and gastric cancer cell lines was detected by qRT-PCR and Western blotting. DLL3/pCMV-Tag4 was transfected into 3 gastric cancer cell lines, and their proliferation was assessed with MTT assay. Human gastric cancer cells MGC803 and MKN45 were also transfected with a specific human DLL3-siRNA to assess the effect of DLL3 down-expression on the cell proliferation. Results The recombinant eukaryotic expression vector DLL3/pCMV-Tag4 was successfully constructed and human full-length DLL3 was expressed in HEK293T cells. MTT assay showed that DLL3 over-expression obviously promoted the proliferation and down-regulation of DLL3 inhibited the proliferation of the gastric cancer cells. Conclusion DLL3 overexpression can promote the proliferation of gastric cancer cells in vitro, and down-regulation of DLL3 inhibits the proliferation of gastrc cancer cells,which provides a novel strategy for targeted thrapy of gastric cancer.

Macrophage as a crucial component of innate immunity, plays an important role in inflammation and infection immunity. Notch signal pathway is a highly conserved pathway, which regulates cellular fate and participates in numerous pathological processes. At present, a lot of literature has confirmed the role of Notch signaling in regulating the differentiation, activation and metabolism of macrophage during inflammation and infection. This review focuses on how Notch signaling promotes macrophage pro-inflammatory and anti-infective immune function in different inflammatory and infectious diseases. In this regulation, Notch signaling interact with TLR signaling in macrophages or inflammatory-related cytokines including IL-6, IL-12, and TNF-α. Additionally, the potential application and challenges of Notch signaling as a therapeutic target against inflammation and infectious diseases are also discussed.
Humans ; Signal Transduction ; Macrophages ; Cytokines/metabolism* ; Inflammation/metabolism* ; Communicable Diseases ; Receptors, Notch/metabolism*