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D Moradpour

Publications and source records attributed to D Moradpour.

70 records · Page 4Linked to original sources
PubMed1996

Efficient gene transfer into mammalian cells with cholesteryl-spermidine.

The naturally occurring polyamine spermidine was covalently conjugated with cholesterol, resulting in a novel cationic compound that mediates efficient gene transfer into mammalian cells. Using reporter plasmids coding for firefly luciferase and beta-galactosidase, a simple procedure was developed allowing highly reproducible and efficient transient and stable transfection of HuH-7 cells. Transfection efficiency could be further increased when a fusogenic peptide derived from the influenza virus hemagglutinin HA2 aminoterminal sequence was included in the cholesteryl-spermidine-DNA complex. Cholesteryl-spermidine (Transfectall) represents a novel cationic compound for efficient transfection of cultured cells in vitro and has the potential to be used for gene transfer in vivo.

3T3 Cells↗
PubMed1996

Characterization of three novel monoclonal antibodies against hepatitis C virus core protein.

Three novel monoclonal antibodies (MAbs) were established against a recombinant hepatitis C virus (HCV) core protein derived from cloned genotype 1b HCV cDNA. MAbs C7-50 and C8-59 recognize a conserved linear epitope represented by amino acid residues 21 to 40 of the nucleocapsid protein. MAb C8-48 is directed against a strain-specific conformational epitope located within the first 82 amino acids. A sensitive two-site MAb-based immunoradiometric assay was established using antibodies directed against distinct epitopes on the nucleocapsid protein. Processed 21 kDa core protein was detected by immunoblotting in human hepatocellular carcinoma cell lines and primary adult rat hepatocytes transfected with a cytomegalovirus promoter-driven expression construct. Immunofluorescence microscopy studies revealed a granular and vesicular cytoplasmic staining pattern. MAb C7-50 was used successfully to detect HCV core antigen in chronically infected chimpanzee liver tissue. These MAbs represent important reagents for the study of HCV biology and for the development of immunodiagnostic assays.

Animals↗
PubMed1996

Expression and immune response to hepatitis C virus core DNA-based vaccine constructs.

Hepatitis C virus (HCV) is a major worldwide cause of acute and chronic hepatitis, cirrhosis, and hepatocellular carcinoma. The development of vaccines against HCV have been complicated by the high variability of the envelope region, and it is likely that the cellular immune responses to viral structural proteins may be important for eradicating persistent viral infection. Recently, it was reported that the injection into muscle cells of plasmids encoding viral genes resulted in the generation of strong cellular immune responses. We constructed vectors that express the highly conserved HCV core gene. In this regard, the pHCV 2-2 construct contained the entire HCV core region and pHCV 4-2 contained both the 5' noncoding region and the core gene. Cellular expression of HCV core protein was assessed following transfection into human and murine cell lines, and higher intracellular levels of the 21-kd core protein were observed with pHCV 2-2. These HCV core DNA constructs were used to immunize BALB/c mice and produced low-level anti-HCV core humoral immune responses. To assess cytotoxic T-lymphocyte (CTL) activity generated in vivo, a cloned syngeneic SP2/O myeloma cell line constitutively expressing HCV core protein was established and inoculated into BALB/c mice to produce growth of plasmacytomas. Strong CTL activity was generated because the tumor size and weight in pHCV 2-2-immunized mice were remarkably reduced compared with mice injected with mock DNA. Spontaneous CTL activity was also exhibited by splenocytes in an in vitro cytotoxicity assay. These investigations demonstrate that plasmid constructs expressing HCV core protein generate strong CTL activity, as assessed both in vivo and in vitro, and are promising candidates as antiviral agents.

Animals↗
PubMed1995

Specific targeting of human hepatocellular carcinoma cells by immunoliposomes in vitro.

The monoclonal antibody AF-20 was raised against the human hepatocellular carcinoma (HCC) cell line FOCUS and binds with high affinity to a rapidly internalized 180-kd homodimeric glycoprotein that is abundantly expressed on the surface of human HCC and other human cancer cell lines. Immunoliposomes were produced by covalently coupling AF-20 to liposomes containing carboxyfluorescein. Interaction of immunoliposomes with various HCC cell lines in vitro was quantitatively assessed by flow cytometry and qualitatively analyzed by fluorescence microscopy. Liposomes bearing an isotype-matched nonrelevant monoclonal antibody (MAb) and cell lines not expressing AF-20 antigen served as controls. AF-20-immunoliposomes specifically bound to HCC and other human cancer cell lines expressing the AF-20 antigen and were rapidly internalized at 37 degrees C. Interaction of AF-20-conjugated liposomes with these cell lines was between 5 and 200 times greater than that of unconjugated liposomes, whereas no difference was observed between control liposomes bearing a nonrelevant antibody and unconjugated liposomes. Specificity of liposome-target cell interaction was confirmed by competitive inhibition assays. Kinetic analysis showed rapid association of AF-20 immunoliposomes with target cells, with saturation conditions being reached after 60 minutes. We conclude that the MAb AF-20 directs highly efficient, specific, and rapid targeting of immunoliposomes to human HCC and other human cancer cell lines in vitro. This targeted liposomal delivery system represents a promising approach for the development of immunotargeted diagnosis and therapy strategies against HCC.

Antibodies, Monoclonal↗
PubMed1994

Chlorpromazine-induced vanishing bile duct syndrome leading to biliary cirrhosis.

We describe a 33-yr-old pregnant woman in whom a primary biliary cirrhosis-like syndrome developed after 2 wk of chlorpromazine therapy. The clinical course was characterized by severe jaundice lasting 22 mo, intense pruritus, fever, steatorrhea, high alkaline phosphatase levels and hypercholesterolemia. Jaundice resolved with initiation of ursodeoxycholic acid therapy, but subclinical cholestasis and low-level inflammatory activity persisted and ultimately evolved into biliary cirrhosis. The pathological substrate of this severe and prolonged cholestatic reaction was found to be the vanishing bile duct syndrome with a marked transient pseudoxanthomatosis.

Adult↗
PubMed1994

The molecular pathogenesis of hepatocellular carcinoma.

Some of the multiple factors involved in the molecular pathogenesis of hepatocellular carcinoma have been elucidated in recent years but no clear picture of how and in what sequence these factors interact at the molecular level has emerged yet. Transformation of hepatocytes to the malignant phenotype may occur irrespective of the aetiological agent through a pathway of chronic liver injury, regeneration and cirrhosis. The activation of cellular oncogenes, the inactivation of tumour suppressor genes and overexpression of certain growth factors contribute to the development of HCC. There is increasing evidence that the hepatitis B virus may play a direct role in the molecular pathogenesis of HCC. Aflatoxins have been shown to induce specific mutations of the p53 tumour suppressor gene thus providing a clue to how an environmental factor may contribute to tumour development at the molecular level.

Animals↗
PubMed1993

[Disseminated toxoplasmosis in AIDS].

Within one year a 46-year-old HIV-positive man developed Pneumocystis carinii pneumonia, candida oesophagitis and recurrent mucocutaneous herpes simplex infections. He finally developed a constant fever without any infection-localizing features. There was pancytopenia, increased activities of the transaminases, lactate dehydrogenase, amylase and lipase, as well as diffuse ST-segment changes in the ECG and discrete pulmonary infiltrates. The anti-toxoplasmosis titre was 8 IU/ml. Despite extensive diagnostic tests no firm diagnosis could be established. The pulmonary infiltrate and the fever regressed under antibiotic treatment with co-trimoxazole. Two months later his general condition deteriorated again with some disorientation and subfebrile temperature, epididymitis and renewed rise in abnormal laboratory values. For the first time computed tomography showed some punctate contrast-medium concentrations in the subcortical area and the medulla. The patient died on the same day. Histological material obtained at the time of autopsy revealed pseudocysts with Toxoplasma gondii and necrotizing inflammation in the brain, myocardium and lungs, as well as the entire gastrointestinal and urogenital tracts. In addition, cytomegalovirus infection of the lung and adrenals was demonstrated. Anti-toxoplasmosis IgG titre, determined postmortem, again registered a marked rise to 251 IU/ml. This suggests that there was reactivation of the toxoplasmosis as part of the immunosuppression process.

AIDS-Related Opportunistic Infections↗
PubMed1991

[Maculopapular rash, pruritus, upper abdominal pain, attacks of dizziness].

A 48 year old male patient presented with maculopapular rash, pruritus, peptic ulcer disease and attacks of headache and vertigo. Rubbing of the cutaneous lesions led to urticarial whealing which is indicative of abnormal mast cell proliferation in the cutis. Histologic evidence of abnormal mast cell proliferation in biopsy specimens of skin and bone marrow led to the diagnosis of systemic mastocytosis. Treatment with H1 and H2 receptor antagonists was started.

Diagnosis, Differential↗
PubMed1991

[Primary sclerosing cholangitis].

In a 40-year-old patient unexplained recurrent attacks of epigastric colic with transient cholestatic icterus occurred over a 9-year period. When the patient was again hospitalised because of progressive pain-free icterus associated with mild pruritus (alkaline phosphatase 900 U/l, direct bilirubin 305 mumol/l, GOT 187 U/l, GPT 103 U/l) sonography revealed liver enlargement to 17 cm, extended intrahepatic bile ducts and an echodense area of about 1 cm size in the region of the bifurcation of the common hepatic duct. Fine-needle puncture did not yield clear cytological findings. Endoscopic retrograde cholangiopancreatography pointed to sclerosing cholangitis. This diagnosis was confirmed by liver punch biopsy. Since the patient did not agree to a liver transplantation, he was treated with 450 mg ursodeoxycholic acid twice daily, resulting in marked reduction of the liver parameters until severe cholangiosepsis and acute renal failure occurred about 4 months later. The septic condition and its complications could not be managed despite thorough intensive-care measures so that a liver transplant had to be performed after all. Histology of the explantate revealed a cholangiocarcinoma in the region of the bifurcation of the common hepatic duct. At first the patient's condition improved markedly but one and half months later the transplant was rejected and the patient died.

Adenoma, Bile Duct↗
PubMed1990

[Nosebleed, vision disorders].

A 79-year-old man had repeated episodes of nose bleeding, disturbances of vision and anemia. Elevated WBC and lymphocytosis suggested chronic lymphatic leukemia. Serum electrophoresis revealed IgM paraproteinemia. The disease progressed rapidly under appropriate therapy. An autopsy revealed NHL of the lymphoplasmocytoid type (IWF: A--LP-immunocytoma), a NHL carrying a slightly poorer prognosis than classical chronic lymphatic leukemia.

Aged↗
PubMedDate not supplied

Independent regulation of two separate gene activities in a continuous human cell line.

Tetracycline- and ecdysone-responsive systems have recently been developed for regulated gene expression in eukaryotic cells. Using nucleolar-targeted luciferase and beta-galactosidase as reporter proteins we demonstrate that both systems can function simultaneously and independently in a continuous human cell line. Both gene activities could be regulated over a broad range and at the single cell level by the concentrations of tetracycline and muristerone A, respectively, in the culture medium. The strategy described here will allow to investigate the function and interaction of two separate gene activities in a well-defined and reproducible cellular context.

Cell Line↗