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D Noël

Publications and source records attributed to D Noël.

12 recordsLinked to original sources
PubMed1998

Genetically engineered antibodies in gene transfer and gene therapy.

Our ability to produce and engineer human monoclonal antibodies provides a basis for the development of novel therapeutical strategies against a variety of diseases. These strategies not only include improved passive immunotherapy but also more sophisticated antibody-based gene therapies involving gene transfer approaches. Four of the major applications of antibody gene engineering in the field of gene therapy are reviewed here. These are (1) the redefinition of viral vector tropism of infection for better transduction of cells of therapeutical interest, (2) the grafting of new cell recognition activities to effector cells of the immune system to kill cancer and pathogen-infected cells, (3) the inhibition of cellular and viral functions through intracellular expression of antibody-derived molecules, and (4) the systemic delivery of therapeutic monoclonal antibodies by non-B cells in living organisms.

Antibodies, Monoclonal↗
PubMed1998

Systemic long-term delivery of antibodies in immunocompetent animals using cellulose sulphate capsules containing antibody-producing cells.

Implantation of capsules containing antibody-producing cells into patients would potentially permit systemic long-term delivery of antibodies and might, thus, be useful in the development of surveillance treatments for cancers and severe viral diseases. We show that cellulose sulphate (CS) capsules containing hybridoma cells, when implanted subcutaneously or in the intraperitoneal cavity, can be used for delivering monoclonal antibodies into the blood-stream of immunocompetent mice for at least several months. In contrast to capsules implanted into the intraperitoneal cavity, which remain mobile and nonvascularized, capsules implanted under the skin form neo-organs which become vascularized within days. This may explain the higher blood concentration of the antibody we have observed in the latter case. Importantly, neither an isolating fibrosis nor an obvious inflammatory response was detected at the capsule implantation sites during observation periods as long as 10 months. Finally, no anti-idiotypic immune response against the ectopically delivered antibody was shown to occur. This rules out any potent adjuvant effect of the cellulose sulphate matrix that might have stimulated a neutralizing humoral response. Taken together, our data indicate that encapsulation of antibody-producing cells into CS might be used in antibody-based gene/cell therapy approaches.

Animals↗
PubMed1997

In vitro and in vivo secretion of cloned antibodies by genetically modified myogenic cells.

In vivo production of recombinant antibodies by engineered cells may have applications for gene therapy of certain cancers and of certain severe viral diseases. It would also permit the development of new animal models of autoimmune diseases and new approaches for in vivo ablation of specific cell types for fundamental purposes. Using gene transfer of an anti-human thyroglobulin monoclonal antibody, we show here that several cell types permitting autologous grafting of genetically engineered cells are efficiently able to secrete antibodies in vitro. Those cells include skin fibroblasts, hepatocytes, and myogenic cells. We also show that the secreted antibodies display an affinity for the antigen close to that of the parental antibody, with, however, slight differences varying according to the cell type. This indicates that the foldings of antigen combining sites of antibodies produced in B cell- and non-B cell contexts are very similar. Finally, we report that, when implanted in the forelimb of a mouse, genetically modified myogenic cells are able to secrete antibodies for at least 4 months. Taken together, our observations point to the notion that genetic modification of patient cells may be used for long-term antibody-based gene therapies.

Animals↗
PubMed1997

Towards efficient cell targeting by recombinant retroviruses.

Efficient human gene therapy will rely on efficient gene delivery systems. To date, recombinant, engineered retroviruses are the most widely used vectors for stable clinical gene transfer. However, this technology still suffers from a number of drawbacks that limit its application. The ability to target cells of therapeutic interest, in particular, would improve both the efficiency and the safety of retroviral vectors. It might also allow the development of new animal models of human diseases and probably extend the scope of gene therapy itself.

Gene Transfer Techniques↗
PubMed1997

[Local anesthesia].

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Anesthesia, Local↗
PubMed1996

Targeted infection of human cells via major histocompatibility complex class I molecules by Moloney murine leukemia virus-derived viruses displaying single-chain antibody fragment-envelope fusion proteins.

As an approach to cell targeting by retroviruses, the lack of which constitutes one major limitation of retroviral vector technology, we engineered the Moloney murine leukemia virus ecotropic envelope glycoprotein. When inserted between amino acids 6 and 7 of the latter, a single-chain antibody fragment (ScFv) specific for human major histocompatibility complex class I molecules was shown to be able to redefine the tropism of ecotropic Moloney murine leukemia virus-derived retroviral particles by allowing infection of major histocompatibility complex class I-positive human cells. At variance with other recently described experimental systems, the type of modification adopted here allowed targeted infection in the absence of coexpressed wild-type env-encoded protein molecules. Interestingly, the chimeric ScFv-env protein also retained the ability to recognize the ecotropic receptor and allowed infection of murine cells, albeit at a reduced efficiency.

3T3 Cells↗
PubMed1986

cDNA clones for liver cytochrome P-450s from individual aroclor-treated rats: constitutive expression of a new P-450 gene related to phenobarbital-inducible forms.

Differential hybridization and screening with cloned inserts was used to identify two families of cytochrome P-450 cDNA clones in libraries prepared from total liver poly(A)+RNA of individual Aroclor-treated rats. One family has cDNA inserts for the major phenobarbital-inducible P-450s, P-450b and P-450e. Two types of P-450e inserts were identified. In addition, irregular inserts were characterized from two clones (PB23 and PB24) of this group. The other family has cDNA inserts for the major 3-methylcholanthrene-inducible species, P-450c and P-450d. No coding sequence restriction site variants were detected among 26 P-450d and P-450c inserts analyzed. The restriction map of the irregular 2.2-kb PB23 insert has a P-450b-like portion, followed by a 3' extension that hybridizes to RNAs of 2.7 and 4.8 kb, which are also detectable with a classical P-450b probe. The PB23 insert and the 2.7- and 4.8-kb RNAs presumably represent 3' extensions of P-450b/P-450e mRNAs, polyadenylated at downstream sites. The 858-bp sequence of the PB24 insert encodes the carboxy-terminal portion of a P-450b/P-450e-like protein. There is approximately 20% divergence at the polypeptide level between the PB24 and P-450b/P-450e sequences; nevertheless, they share many essential features. A PB24-specific probe hybridizes to a 1.9-kb RNA species which is present in the liver of untreated rats and which is not appreciably induced by phenobarbital or Aroclor. The PB24 cDNA most likely represents a constitutive cytochrome P-450, related to phenobarbital-inducible forms.

Amino Acid Sequence↗
PubMed1980

Liquid-chromatographic measurement of urinary monosaccharides.

We describe "high-performance" liquid chromatography of urinary monosaccharides on a macroporous anion-exchange resin (Hitachi 3013N), with acetonitrile/water as eluent. The separated xylose, arabinose, D-fructose, mannose, galactose, and D-glucose were detected by means of a post-column reduction reaction of tetrazolium blue. Absolute limits of detection were about 10 ng of monosaccharide. Lactose can also be measured.

Child↗
PubMed1979

[Upper gastrointestinal haemorrhage in the patients aged over 65 years. The contribution of endoscopy (author's transl)].

One hundred and eighty four patients aged over 65 years and hospitalised for gastrointestinal haemorrhage of high origin underwent emergency oesophago-gastro-duodenoscopy. It was thereby possible to make an aetiological diagnosis in 94.5% of cases. The study demonstrated certain special features: the preponderance of acute gastro-duodenal lesions, possibly explained by the high consumption of gastrotoxic drugs in the elderly subject; the relative frequency of oesophagitis (11%), one out of two cases being responsible for the bleeding; the discovery of a hiatal hernia in 59 patients (1/3 of cases), 25% of them bleeding from a lesion directly related to the latter. Bleeding was in large quantity in 57% of cases. Mortality, which was quite high (17%) appeared to be more related to the underlying general condition than to the haemorrhage itself. Endoscopy gave rise to complications in 8 patients, including 3 who died.

Aged↗
PubMed1979

[Hemochromatosis and puryvate kinase deficiency (author's transl)].

A 25-year-old man with familial pyruvate kinase (PK) deficiency who have been given only 6 transfusions during his lifetime died of cardiac failure from hemochromatosis (HC). This previously unreported association of PK and HC deficiency does not appear to be fortuitous but to be related to possible early hemolysis and intramedullary destruction, features of ineffective erythropoiesis. The role of splenectomy in the progression of the HC could, as in some thalassemias, be an unfavourable factor. Serum iron levels should therefore be measured during the course of AHPK.

Adult↗
PubMedDate not supplied

Phagocytosis associated chemiluminescence of hemocytes in Mytilus edulis (Bivalvia).

The respiratory burst associated with phagocytosis by Mytilus edulis hemocytes was investigated by measurement of luminol-dependent chemiluminescence (LDCL). After experimental parameters (number of cells, quantity of stimulus) were determined, the biochemical mechanisms involved in the chemiluminescent process were investigated using inhibitors of oxygen radicals and enzymes. In particular, catechol-like phenols suggested the involvement of NADPH-oxidase and peroxidase in oxidative metabolism of mussel hemocytes. The variability of LDCL response observed among individuals and separated hemocyte subpopulations strongly suggests a variable immunocapacity depending on hemogram composition. Using a specific monoclonal antibody to discriminate different hemocyte types, the eosinophilic granulocytes appeared to exhibit the highest LDCL activity.

Animals↗