OBJECTIVETo investigate the expression of gastrin in human gastric cancer cell line SGC-7901 and the effects of gastrin-17 and anti-gastrin mAb on its growth.

METHODSThe expression of gastrin was determined by immunohistochemistry with anti-gastrin mAb prepared by our group. In a series of experiments, the growth of SGC-7901 cells was evaluated by MTT assay on cells grown in serum-free medium and treated with gastrin-17 and/or anti-gastrin mAb.

RESULTSImmunohistochemical examination of SGC-7901 cells revealed a specific gastrin immunoreactivity. Gastrin-17 significantly stimulated cell growth at the concentrations of 1 x 10(-9) mol/L approximately 1 x 10(-5) mol/L in a dose-dependent manner. The growth of SGC-7901 cells treated with anti-gastrin mAb, either alone or in combination with gastrin-17 (1 x 10(-7) mol/L), was significantly inhibited.

CONCLUSIONGrowth of human gastric cancer cells SGC-7901 can be stimulated in an autocrine fashion. The gastrin-stimulated growth of gastric cancer cells can be blocked by anti-gastrin mAb bound specifically with gastrin. Further study on the significance of anti-gastrin mAb in designing immunotherapy targeting to gastrin or gastrin receptor is warranted.

Antibodies, Monoclonal ; pharmacology ; Cell Line, Tumor ; Cell Proliferation ; Gastrins ; biosynthesis ; genetics ; immunology ; Humans ; Receptor, Cholecystokinin B ; biosynthesis ; genetics ; Stomach Neoplasms ; metabolism ; pathology

The study was purposed to investigate the effects of humanized recombined CD25 monoclonal antibody (rhCD25MAb) on activation and proliferation of T lymphocytes in vitro. Peripheral blood mononuclear cells (PBMNC) were incubated with phytohemagglutinin (PHA). Before or after T cell activation, the cells were cultured with or without rhCD25MAb or cyclosporine A (CsA) in vitro. After 72 hours incubation, the proliferation of lymphocytes was analyzed by MTT assay. The expression of CD3 and CD25 antigens on T lymphocytes were detected by flow cytometry. The levels of sIL-2R in the supernatants were determined with ELISA. The results showed that both rhCD25MAb and CsA could inhibit the proliferation of T lymphocytes significantly in concentration-dependent manner and CsA was more efficient than rhCD25MAb. Both rhCD25MAb and CsA could also decrease the levels of sIL-2R in the supernatant and inhibit the expression of CD25 antigen on T lymphocytes. The level of sIL-2R and the expression of CD25 on T lymphocytes decreases more profoundly in rhCD25MAb group. It is concluded that rhCD25MAb shows strong immunosuppressive activity both before and after T cell activation, suggesting that this agent may be useful in not only prophylaxis but also the treatment of acute graft-versus-host disease.
Antibodies, Monoclonal ; pharmacology ; CD3 Complex ; biosynthesis ; genetics ; Cell Proliferation ; Cells, Cultured ; Cyclosporine ; pharmacology ; Humans ; Immunosuppressive Agents ; pharmacology ; Interleukin-2 Receptor alpha Subunit ; biosynthesis ; genetics ; immunology ; Lymphocyte Activation ; immunology ; Receptors, Interleukin-2 ; analysis ; Recombinant Proteins ; immunology ; pharmacology ; T-Lymphocytes ; immunology

OBJECTIVETo investigate the effect of anti-ICAm-1/LAF-1 McAb on the cytotoxicity of tumor infiltrating lymphocytes from oral squamous cell carcinoma.

METHODSTIL were isolated from fresh tumor tissues in 15 patients with oral squamous cell carcinoma and cultured in vitro. The expression of ICAM-1/LAF-1 in fresh and activated TIL was examined by FACS. The cytotoxicity of TIL against auto tumor cells and the level of TNF-alpha produced by TIL were compared before and after interrupted with anti-ICAM-1/LAF-1 McAb.

RESULTSThe expression of ICAM-1 and LAF-1 in the activated TIL significantly increased comparing with fresh TIL (P < 0.05). Interrupted by anti-ICAM-1 McAb, the cytotoxicity of TIL against auto tumor cell was not significantly changed. Interrupted by anti-ICAM-1 and anti-LAF-1 McAb, the level of TNF-alpha produced by TIL showed no differences comparing with the control (P < 0.05), but the cytotoxicity of TIL against auto tumor cells significantly decreased (P < 0.05).

CONCLUSIONThe effect of anti-LAF-1 McAb may result from steric interference of antigen-nonspecific adhesion process.

Antibodies, Monoclonal ; pharmacology ; Carcinoma, Squamous Cell ; immunology ; pathology ; Cells, Cultured ; Cytotoxicity, Immunologic ; Female ; Humans ; Intercellular Adhesion Molecule-1 ; biosynthesis ; genetics ; Lymphocyte Function-Associated Antigen-1 ; biosynthesis ; genetics ; Lymphocytes, Tumor-Infiltrating ; immunology ; pathology ; Male ; Mouth Neoplasms ; immunology ; pathology

Equine interferon-gamma (eIFN-gamma) expressed both in E. coli and baculovirus were evaluated for antiviral activity against recombinant Vesicular Stomatits Virus expressing green fluorescence protein (rVSV-GFP) in EFK-78 cells. The assays were conducted in 96-well plate. Virus infectivity was measured by quantifying GFP-positive cells, instead of quantifying the CPE reduction. Prior to infection of EFK-78 cells with rVSV-GFP, the cells were incubated with eIFN-gamma. The GFP expression in the EFK-78 cells dramatically decreased in the cells treated with eIFN-gamma in a dose-dependent manner, comparing with the mock-treated cells. The titers of antiviral activity were 1 x 10(3) AU/mL and 1 x 10(5) AU/mL of eIFN-gamma expressed from E. coli and baculovirus, respectively. The antiviral activities of the recombinant eIFN-gamma were highly efficient and specific, as it was blocked by mAbs against eIFN-gamma.
Animals ; Antibodies, Monoclonal ; immunology ; Antiviral Agents ; metabolism ; pharmacology ; Baculoviridae ; genetics ; metabolism ; Escherichia coli ; genetics ; metabolism ; Green Fluorescent Proteins ; metabolism ; Horses ; Interferon-gamma ; biosynthesis ; genetics ; pharmacology ; Recombinant Proteins ; Vesicular stomatitis Indiana virus ; drug effects ; metabolism

OBJECTIVETo investigate the effect of fas gene transfection and monoclonal anti-fas antibody on tumorigenicity and proliferation of transplanted tumor of Tca8113 cell.

METHODSPlasmid including fas gene was transfected into Tca8113 cell by lipofectamine kit. Some transfected cells were treated by monoclonal anti-fas antibody after 48 hours since transfection. Untransfected cell (control), fas-tansfected cell and fas-transfected cell treated with antibody were transplanted to nude mice subcutaneously. Growth of transplanted tumor was observed and recorded regularly. Animals were sacrificed and tumor samples were harvested at the end of experiment. Fas expression in each neoplasm was assessed by RT-PCR. Apoptosis, proliferation and expression of fas protein in tumor tissue were measured by flow cytometry (FCM).

RESULTSTumor occurred much later in fas-transfected group and fas-transfected plus antibody treated group. Growth arrest was found in them. RT-PCR and FCM suggested that fas-transfection up-regulated the expression of fas mRNA and protein, increased apoptosis index (AI). But no effect on proliferation index (PI) was observed. Monoclonal anti-fas antibody did not effect the expression of fas mRNA and protein, but increased AI and decreased PI.

CONCLUSIONFas-transfection suppressing tumorigenesis of Tca8113 cell transplanted in nude mice might be caused by up-regulation of expression of fas gene and enhancement of apoptosis. However, anti-fas antibody suppressing tumorigenesis might be associated with activation of apoptosis and repression of proliferation.

Animals ; Antibodies, Monoclonal ; pharmacology ; Apoptosis ; drug effects ; Carcinoma, Squamous Cell ; metabolism ; pathology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Fas Ligand Protein ; biosynthesis ; genetics ; pharmacology ; Humans ; Mice ; Mice, Inbred BALB C ; Mouth Neoplasms ; metabolism ; pathology ; RNA, Messenger ; genetics ; Transfection

OBJECTIVETo study the regulation of Fc receptor expression by immune complexes (ICs) on neutrophils and U937 cells.

METHODSIgA ICs, IgG1 ICs, IgG2 ICs, IgG3 ICs, IgG4 ICs, and IgM ICs were incubated with neutrophils or U937 cells for 1 h. Then their surface Fc receptors were stained by anti-Fc gammaR I, anti-Fc gammaR II , anti-Fc gammaR III, and anti-Fc alphaR I monoclonal antibodies and analyzed by fluorescent activated cell sorting (FACS).

RESULTSIgG1 ICs and IgG3 ICs up-regulated Fc gammaR II and Fc gammaR III on U937 cells, Fc gammaR I and Fc alphaR I on neutrophils. Almost all ICs down-regulated Fc gammaR II on neutrophils.

CONCLUSIONSICs can regulate Fc receptor expression on neutrophils and U937 cells, among which IgG1 ICs and IgG3 ICs are most effective.

Antibodies, Anti-Idiotypic ; immunology ; Antibodies, Monoclonal ; pharmacology ; Antigen-Antibody Complex ; immunology ; metabolism ; Antigens, CD ; immunology ; Humans ; Immunoglobulin A ; classification ; immunology ; Immunoglobulin G ; chemistry ; classification ; immunology ; metabolism ; Neutrophils ; metabolism ; Receptors, Fc ; biosynthesis ; genetics ; Receptors, IgG ; immunology ; U937 Cells ; immunology

BACKGROUND/AIMS: To develop a novel treatment method for hepatitis B virus (HBV) infection, we aimed to make a human monoclonal antibody inhibiting reverse transcriptase (RT) activity of P protein which was important in HBV replication by using phage display technique. Therefore, we analysed the usability of human monoclonal antibody as a protein based gene therapy. METHODS: Reverse transcriptase/polymerase (RT/POL) functional motif of P protein of HBV was cloned in pMAL-c vector and expressed as maltose binding fusion protein form. The RT/POL recombinant protein (pMRT/POL) was purified by amylose resin column. Using human single chain Fv phage antibody library with 1.1x10(10) size, human antibody against pMRT/POL was selected with BIAcore panning. Selected antibody fragments were analyzed for the activity of RT inhibition. Finally, they were analyzed for the affinity with BIAcore and the complementarity determining regions with nucleotide sequencing. RESULTS: pMRT/POL recombinant protein expressed in E. coli showed RT activity, 1microgram of recombinant protein had an activity equivalent to 5 unit of MMLV RT. By BIAcore panning, we could select 3 clones; POL-A5, POL-B8 and POL-B12. Each clone's RT inhibiting activity were 52-82%, affinity against antigen were 8.15x10(-8) M to 1.75x10(-6) M. CONCLUSIONS: Human monoclonal antibodies produced in this study showed low affinity, but efficiently inhibited the activity of RT in vitro. If POL-A5, POL-B8, and POL-B12 can be converted to intracellular antibody form, it can be used for protein-based gene therapy by inhibiting the replication through the neutralization of polymerase protein of HBV.
Antibodies, Monoclonal/biosynthesis/genetics/*pharmacology ; Complementarity Determining Regions/chemistry ; Gene Products, pol/*antagonists & inhibitors/genetics/immunology ; Genetic Vectors ; Hepatitis B virus/enzymology/genetics ; Humans ; Peptide Library ; RNA-Directed DNA Polymerase/genetics/*immunology ; Recombinant Fusion Proteins/biosynthesis/genetics ; Reverse Transcriptase Inhibitors/chemistry/metabolism/*pharmacology

OBJECTIVETo investigate the blockness effects of purified polyclonal anti-porin I antibody on N. gonorrhoeae adherence to genitourinary tract epithelia of BALB/c mouse.

METHODSPolyclonal anti GST-PI antibody was generated by immunizing rabbit with GST-PI fusion protein which was constructed and expressed by ourselves. The purified immunoglobulin G was obtained by ammonium sulphate deposition and DEAE cellulose chromatography. Mice model of gonorrhea was established. In order to evaluate the effects of PI-IgG on gonococcus adhesion to vagina mucus, the macroscopic and pathological assessing as well as gonococcus culture was employed after gonococcus challenge on PI-IgG immunized mice.

RESULTNo pus and pathological inflammation were observed on mice vagina mucus treated with 1 mg/ml PI-IgG 3 hours before gonococcus challenge. Gonococcus could not be detected in the smears and washing solutions from vagina. Pathological inflammation was found in mice treated with anti PI-IgG, in which the concentrations were lower than 1 mg/ml or the treated time was longer than 3 hours prior to gonococcus challenge.

CONCLUSIONThe purified anti PI-IgG can effectively inhibit the adherence and infection of gonococci to genitourinary tract epithelia of BALB/c mice. In addition, the blocking duration of anti PI-IgG is associated with antibody concentration.

Animals ; Antibodies, Monoclonal ; pharmacology ; Bacterial Adhesion ; drug effects ; Epithelium ; drug effects ; microbiology ; Female ; Glutathione Transferase ; biosynthesis ; genetics ; Gonorrhea ; microbiology ; prevention & control ; Mice ; Mice, Inbred BALB C ; Neisseria gonorrhoeae ; drug effects ; physiology ; Porins ; biosynthesis ; genetics ; immunology ; Rabbits ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; immunology ; Urogenital System ; drug effects ; microbiology

OBJECTIVETo investigate the antitumor efficacy of death receptor 5, its ligand (TRAIL) and DR5mAb in human hepatocellular carcinoma.

METHODSExpression of DR5 in the HCC cell lines HepG2, SMMC 7721 and normal human liver cell line LO2 was measured at mRNA and protein level by semi-quantitative RT-PCR and Western blot, respectively. MTT method was used to measure the cell viability and flow cytometry assay was used to detect apoptosis so as to observe the inhibitory effect of TRAIL and DR5mAb on HCC cells.

RESULTSDeath receptor 5 was highly expressed in the HCC cell lines, but rarely expressed in normal human liver cell line (P < 0.01). With the increase of TRAIL concentration, the cell viability of HCC cells decreased gradually. However, when the concentration of TRAIL was above 1000 ng/ml, HCC cells were resistant to TRAIL, but still sensitive to DR5mAb. After incubation with DR5mAb (1000 ng/ml) for 24 h, the rate of apoptosis in HCC cells reached to 52.45% +/- 0.57%, which was higher than that incubated with TRAIL under the same condition (14.74% +/- 0.48%) (P < 0.05). The cell viability of normal human liver cell line treated with TRAIL tended to decline with the increase of the concentration, which was significantly different from that of matched control group. But DR5mAb had little effect on normal human liver cell line.

CONCLUSIONDeath receptor 5 as a target plays an important role in the course of HCC apoptosis induction. Agonistic monoclonal antibody specific for human DR5 can selectively and effectively kill hepatocellular carcinoma cells in vitro, while is not harmful to normal human hepatocytes. It reveals that DR5mAb might provide a new direction in hepatocellular carcinoma treatment research.

Antibodies, Monoclonal ; pharmacology ; Apoptosis ; drug effects ; Carcinoma, Hepatocellular ; metabolism ; pathology ; Cell Line ; Cell Line, Tumor ; Cell Survival ; drug effects ; Humans ; Liver Neoplasms ; metabolism ; pathology ; RNA, Messenger ; biosynthesis ; genetics ; Receptors, TNF-Related Apoptosis-Inducing Ligand ; biosynthesis ; genetics ; immunology ; TNF-Related Apoptosis-Inducing Ligand ; biosynthesis

OBJECTIVETo observe the preventive effect of multi-glycoside of Tripterygium Wilfordii Hook. f. (GYW) on proteinuria and mesentery injury in experimental mesangial proliferative glomerulonephritis in vivo.

METHODSThe reversible anti-Thyl.1 antibody glomerulo nephritis model of rats was established with monoclonal antibody 1-22-3 and intervened with GTW, and a control group was set up in the same time. Changes of 24h urinary protein excretion, serum creatinine (Scr), blood urea nitrogen (BUN), total plasma protein (TP) and glomerular morphology were observed, and the level of mRNA expression of proliferative factors, including platelet-derived growth factor-BB (PDGF-BB) and transforming growth factor-beta (TGF-beta), in renal tissue was determined.

RESULTSGTW could inhibit proteinuria and mesangial injury in anti-Thyl. 1 antibody nephritis model. The PDGF-BB and TGF-beta mRNA expression in the anti-Thy1.1 antibody nephritis model rats were increased for 2.84 and 1.64 times respectively to those in the normal control group. GTW could down-regulate the over-expression of PDGF-BB mRNA by 33.1%, it was significantly different to that in the control group (P < 0.05).

CONCLUSIONGTW could reduce the proteinuria and inhibit mesangial cells proliferation and extracellular matrix deposition, these effects maybe related to the down-regulating of PDGF-BB mRNA expression.

Animals ; Antibodies, Monoclonal ; immunology ; Drugs, Chinese Herbal ; therapeutic use ; Female ; Glomerular Mesangium ; pathology ; Glomerulonephritis, Membranoproliferative ; chemically induced ; metabolism ; prevention & control ; Glycosides ; isolation & purification ; pharmacology ; therapeutic use ; Phytotherapy ; Plant Extracts ; therapeutic use ; Platelet-Derived Growth Factor ; biosynthesis ; genetics ; Proteinuria ; prevention & control ; Proto-Oncogene Proteins c-sis ; Random Allocation ; Rats ; Rats, Wistar ; Thy-1 Antigens ; immunology ; Transforming Growth Factor beta ; biosynthesis ; genetics ; Tripterygium ; chemistry