Neural cell adhesion molecule (NCAM) is a glycoprotein expressing on the surface of neurons, glial cells, bone cells and natural killer cells. NCAM plays an important role in the process of cell - cell adhesion and cell migration, and is also a model protein to study polysialic acid. In this paper, NCAM gene from mouse mammary gland cells (NMuMG) was cloned into eukaryotic expression vectors pcDNA3.1(+) and transfected into mutant Chinese hamster ovary cells ldlD-14. The stable transfection over-expressing NCAM was obtained through the G418 selection and confirmed by Western blotting. Due to unique characters of ldlD-14 cells, carbohydrate chain of NCAM molecule can be easily manipulated with or without adding galactose in the serum free medium, and this modification can provide the basis for further studies on the effect of glycosylation on NCAM molecular function.
Animals ; CHO Cells ; Cloning, Molecular ; Cricetinae ; Cricetulus ; Female ; Galactose ; Glycosylation ; Mammary Glands, Animal ; cytology ; Mice ; Neural Cell Adhesion Molecules ; biosynthesis ; Polysaccharides ; chemistry ; Sialic Acids ; chemistry ; Transfection

The purpose of this study was to detect the serum PTK7 level of patients with acute lymphocytic leukemia, and to reveal its clinical value for diagnosis of diseases. A total of 136 patients diagnosed as acute lymphocytic leukemia from May 2012 to April 2014 in our hospital were enroled in this study and were divided into the L1 group (n = 42), L2 (n = 45) and L3 group (n = 49) according cytomorphology, and 48 normal children were selected as control group. Fluorescence quantitative PCR was used to detect mRNA level of PTK7 in peripheral blood mononuclear cells, and Western blot was used to detect PTK7 protein expression. The results showed that the PTK7 mRNA level in L1 group was significantly higher than that in normal group (P = 0.000) . The PTK7 mRNA level in L2 group was significantly higher than that in the L1 group (P = 0.000). The PTK7 mRNA level in L3 group and L2 group had not significantly different between each other (P = 0.123). Serum PTK7 protein level in L1 group was very significantly higher than that in normal group (P = 0.000) . The serum PTK7 protein level in L2 group were very significantly higher than that in the L1 group (P = 0.003) and serum PTK7 protein level in L3 and L2 group had no significance difference (P = 0.312) . It is concluded that the expression level of serum PTK7 protein has a potential clinical value for the diagnosis of acute lymphocytic leukemia, but without specificity for ALL subsets.
Cell Adhesion Molecules ; blood ; genetics ; Humans ; Leukocytes, Mononuclear ; metabolism ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; blood ; diagnosis ; genetics ; RNA, Messenger ; biosynthesis ; blood ; genetics ; Receptor Protein-Tyrosine Kinases ; blood ; genetics

OBJECTIVETo explore the effect of down-regulation of astrocyte elevated gene-1 (AEG-1) expression on cell proliferation and cell cycle of gastric carcinoma cells, and its possible molecular mechanism.

METHODSControl siRNA and AEG-1 siRNA were transfected into gastric carcinoma SGC-7901 cells. 48 h after transfection, the cells were divided into 3 groups including untransfected, siRNA control and AEG-1 siRNA transfection groups. Expressions of AEG-1 mRNA and protein in the 3 group cells were detected by real-time quantitative PCR and Western blot. The changes of cell proliferation were examined using CCK-8 kit, and the cell cycle distribution was detected by flow cytometry. Finally, expressions of cell proliferation and cell cycle related proteins were detected by Western blot.

RESULTSReal-time quantitative PCR and Western blot demonstrated that compared with the untransfected and siRNA control groups, expressions of AEG-1 mRNA and protein were significantly down-regulated in the AEG-1 siRNA transfection group (P < 0.05), but there was no significant difference between the untransfected and siRNA control groups (P > 0.05). Furthermore, in vivo experiment confirmed a significant down-regulation of AEG-1 protein in the AEG-1 siRNA transfection group (P < 0.05). In addition, AEG-1 siRNA obviously inhibited the proliferation of SGC-7901 cells at different time points after transfection with AEG-1 siRNA. The percentage of cells in G0/G1 phase in the AEG-1 siRNA transfection group [(61.26 ± 1.25)%] was significantly higher than those in the untransfected group [(46.17 ± 1.91)%] and siRNA control group [(46.46 ± 1.96)%], and there was a significant difference between them (all P < 0.001). Furthermore, the result of Western blotting revealed that down-regulation of AEG-1 expression evoked the down-regulation of cdk2 and cyclin D1 expressions and elevation of p21 expression in vitro and in vivo.

CONCLUSIONSThe inhibition of cell proliferation and cell cycle arrest mediated by down-regulation of AEG-1 expression may be closely associated with the changes of expression of cell cycle related proteins including cdk2, cyclin D1 and p21.

Animals ; Cell Adhesion Molecules ; biosynthesis ; genetics ; Cell Cycle Checkpoints ; Cell Line, Tumor ; Cell Proliferation ; Cyclin D1 ; metabolism ; Cyclin-Dependent Kinase 2 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p21 ; metabolism ; Down-Regulation ; Female ; Humans ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Neoplasm Transplantation ; RNA Interference ; RNA, Messenger ; metabolism ; RNA, Small Interfering ; genetics ; Stomach Neoplasms ; metabolism ; pathology ; Transfection

Down syndrome cell adhesion molecule (DSCAM) acts as a netrin-1 receptor and mediates attractive response of axons to netrin-1 in neural development. However, the signaling mechanisms of netrin-DSCAM remain unclear. Here we report that AMP-activated protein kinase (AMPK) interacts with DSCAM through its γ subunit, but does not interact with DCC (deleted in colorectal cancer), another major receptor for netrin-1. Netrin-treatment of cultured cortical neurons leads to increased phosphorylation of AMPK. Both AMPK mutant with dominant-negative effect and AMPK inhibitor can significantly suppress netrin-1 induced neurite outgrowth. Together, these findings demonstrate that AMPK interacts with DSCAM and plays an important role in netrin-1 induced neurite outgrowth. Our study uncovers a previously unknown component, AMPK, in netrin-DSCAM signaling pathway.
AMP-Activated Protein Kinases ; antagonists & inhibitors ; genetics ; metabolism ; Animals ; Cell Adhesion Molecules ; genetics ; metabolism ; Cells, Cultured ; HEK293 Cells ; Humans ; Mice ; Nerve Growth Factors ; pharmacology ; Netrin-1 ; Neurites ; physiology ; Neurons ; cytology ; drug effects ; metabolism ; Phosphorylation ; Protein Binding ; Protein Kinase Inhibitors ; pharmacology ; RNA Interference ; RNA, Small Interfering ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; Signal Transduction ; drug effects ; Transfection ; Tumor Suppressor Proteins ; pharmacology

As a severe threat to human health, ischemic brain injury has a very complex pathological mechanism involving excitotoxic amino acids, oxygen free radical formation, nitric oxide (NO), Ca2+ overload and inflammation. Traditional Chinese medicine Qingkailing injection have shown good clinical efficacy in the treatment of cerebrovascular disease, and thus it is very significant to studies on its pharmacological mechanism. This essay summarizes relevant studies on pharmacological mechanism of a new compound traditional Chinese medicine Jingzhiqiangkailing (JZQKL) injection in treatment on cerebral ischemia, and explains the pharmacological mechanism of its single effective compounds and their compatibility in treatment of schemic brain injury in the aspects of regulating inflammatory response, neurotrophic factors, vascular protection, blood-brain barrier (BBB) protection and others, and thus providing information for further studies.
Animals ; Blood-Brain Barrier ; drug effects ; Brain Ischemia ; drug therapy ; Cell Adhesion Molecules ; physiology ; Cytokines ; biosynthesis ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Humans ; Injections ; Nerve Growth Factors ; physiology

OBJECTIVETo construct a eukaryotic expression vector of CD99 gene for transfection into Hodgkin lymphoma L428 cells.

METHODSThe full-length cDNA of CD99 gene was amplified from Jurkat cells by RT-PCR and cloned into the pcDNA3.1(+) vector and transfected into L428 cell line using Lipofextamine 2000. The sequence of CD99 mRNA in the transfected cells was confirmed by restriction endonuclease digestion and DNA sequencing, and the expression of CD99 protein was identified using immunocytochemistry.

RESULTSA gene fragment of 558 bp was amplified from the transfected cells and the sequence was verified by DNA sequencing. Immunocytochemistry identified the presence of CD99 expression in the transfected cells.

CONCLUSIONA eukaryotic expression vector pcDNA3.1(+)-CD99 is successfully constructed and stably expressed in L428 cell line.

12E7 Antigen ; Antigens, CD ; biosynthesis ; genetics ; Base Sequence ; Cell Adhesion Molecules ; biosynthesis ; genetics ; Cell Line, Tumor ; Cloning, Molecular ; Genetic Vectors ; genetics ; Hodgkin Disease ; metabolism ; pathology ; Humans ; Jurkat Cells ; Molecular Sequence Data ; Transfection

To prolong serum half-life of human kallikrein (hK) and enhance its secretion rate, we modified hK gene and constructed a new form of recombinant hK protein (hK'-Fc). We amplified hK gene and Fc sequence, replaced the signal peptide of hK gene with murine signal peptide, constructed native expression plasmid of pcDNA-hK-Fc and modified expression plasmid of pcDNA-hK'-Fc, then transfected to CHO cells respectively. After the stable cell lines were screened, we compared the secretion rate between native fusion protein and modified fusion protein, purified fusion protein through Protein A+G affinity chromatography column and investigated the bioactivity of fusion protein. The results showed that recombinant vectors encoding fusion protein hK-Fc and hK'-Fc were constructed successfully; CHO cell lines stably secreting fusion protein were obtained, the yield is higher than 11 mg/L; Secretion rate was enhanced by 5-10 times after the signal peptide of fusion protein was modified; Fusion protein has enzymatic activity in vitro. The above results could promote the following researches on serum half-life of the fusion protein and develop a new stroke medicine with better clinical efficacy.
Animals ; CHO Cells ; Cell Adhesion Molecules ; biosynthesis ; genetics ; Cricetinae ; Cricetulus ; Humans ; Mice ; Protein Sorting Signals ; genetics ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; physiology ; Tissue Kallikreins ; biosynthesis ; genetics ; Transfection

OBJECTIVETo investigate the significance of trophinin expression in human oocytes and preimplantation embryos.

METHODSThe expression of trophinin in 9 human oocytes, 16 blastomeres and 12 blastocysts were detected by indirect immunofluorescence assay and observed under laser scanning confocal microscope.

RESULTSHuman oocytes, blastomeres and blastocysts were all positive for trophinin expression, and the positivity intensified significantly in the course of the embryonic development (P<0.05).

CONCLUSIONTrophinin may play an important role in human embryo implantation by mediating homophilic adhesion between the embryo and the endometrium during the implantation window.

Blastocyst ; metabolism ; Cell Adhesion Molecules ; biosynthesis ; Female ; Fluorescent Antibody Technique, Indirect ; Humans ; Microscopy, Confocal ; Oocytes ; metabolism ; Pregnancy

OBJECTIVETo clone migfilin-N terminal sequence into E.coli and obtain a fusion protein for preparing rabbit polyclonal antibody against migfilin, thereby facilitating the study of the role of migfilin in the biological behavior of colon cancer.

METHODSBased on human migfilin cDNA sequence, a pair of primers was designed to amplify migfilin-N terminal sequence by PCR. The PCR product was subcloned into the bacterial expression vector pGEX-4T-1 with EcoRI/XhoI sites, and the target recombinant plasmids were identified with enzymatic cleavage followed by DNA sequence analysis. By transforming the expression vector into component E.coli BL(21) cells, the GST-migfilin-N fusion protein was expressed with IPTG induction. Glutathione-sepharose beads were used to purify the fusion protein, and anti-migfilin polyclonal antibody was produced by immunization of rabbits with the purified GST-migfilin N-terminal fusion protein. The resultant anti-migfilin polyclonal antibody was purified by protein A beads and used for Western blotting for detecting migfilin expression in different cell lines.

RESULTS AND CONCLUSIONThe migfilin-N terminal gene fragment was cloned successfully, and purified GST-migfilin N-terminal fusion protein and anti-rabbit migfilin polyclonal antibodies were obtained. Western blot analysis demonstrates that the antibodies specifically detected migfilin expression in the cell lines, which may facilitate further investigation of the role of migfilin in the biology of colon cancer.

Animals ; Antibodies, Monoclonal ; biosynthesis ; immunology ; isolation & purification ; Base Sequence ; Blotting, Western ; Cell Adhesion Molecules ; genetics ; immunology ; Cell Line, Tumor ; Cloning, Molecular ; Colonic Neoplasms ; genetics ; metabolism ; pathology ; Cytoskeletal Proteins ; genetics ; immunology ; DNA, Complementary ; chemistry ; genetics ; Escherichia coli ; genetics ; Humans ; Molecular Sequence Data ; Rabbits ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; immunology ; Reverse Transcriptase Polymerase Chain Reaction ; Sequence Analysis, DNA

The aim of this study was to evaluate the effect of all-trans retinoic acid (ATRA) on cell adhesion molecule expression and adhesion capacity of bone marrow stromal cells (BMSC) in patients after conditioning treatment for peripheral blood stem cell transplantation (PBSCT). BMSC of 27 patients before and after conditioning treatment for PBSCT were cultured in vitro. After treated with ATRA at 0.01, 0.1, or 1 micromol/L, expression of intercellular adhesion molecule-1 (ICAM-1) protein and vascular adhesion molecule-1 (VCAM-1) protein were detected by flow cytometry, and soluble ICAM-1 (sICAM-1) protein was determined by using radioimmunoassay. Then BMSC was co-cultured with CD34+ cells, and adhesion rate of BMSC to CD34+ cells was measured. The results showed that after pretreatment with conditioning regimen for PBSCT, the expressions of ICAM-1 and VCAM-1 proteins in BMSC and the expression level of sICAM-1 protein in supernatant of BMSC culture were down-regulated, and the adhesion rate of BMSC to CD34+ cells was decreased, after administration of ATRA, the expression of ICAM-1 protein in BMSC, sICAM-1 protein in culture medium and adhesion rate of BMSC to CD34+ cells all increased significantly, but expression of VCAM-1 protein changed no significantly. It is concluded that the ATRA can partly restore adhesion function of BMSC injured by pretreatment for PBSCT and contribute to hematopoietic reconstitution.
Adolescent ; Adult ; Antigens, CD34 ; Antineoplastic Agents ; pharmacology ; Bone Marrow Cells ; metabolism ; pathology ; Cell Adhesion ; drug effects ; Cell Adhesion Molecules ; biosynthesis ; genetics ; Child ; Coculture Techniques ; Hematologic Neoplasms ; metabolism ; pathology ; therapy ; Humans ; Middle Aged ; Peripheral Blood Stem Cell Transplantation ; Stromal Cells ; metabolism ; pathology ; Tretinoin ; pharmacology ; Tumor Cells, Cultured ; Vascular Cell Adhesion Molecule-1 ; biosynthesis ; genetics