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F Faure

Publications and source records attributed to F Faure.

At least 37 records · Page 2Linked to original sources
PubMed1988

CD3/Ti gamma A: a functional gamma-receptor complex expressed on human peripheral lymphocytes.

We have recently developed a mAb designated anti-Ti gamma A, which was found to immunoprecipitate from the well characterized CD3+ TCR alpha/beta- F6C7 fetal clone a CD3-associated disulfide-linked gamma-glycoprotein. This antibody recognizes approximately 3% of adult peripheral lymphocytes and delineates a CD2+ CD3+ TCR alpha/beta- CD4- NKH1- subset where expression of CD8 appears to vary widely from one individual to another. In the present study, we have used anti-Ti gamma A mAb to assess whether gamma-chains expressed on these adult lymphocytes are used as functional R. The two activities which have been associated thus far with TCR gamma+ cells, that is, IL-2-dependent proliferation and non-MHC-restricted cytotoxicity, were investigated here by using either resting or activated Ti gamma A+ lymphocytes. On the resting state, these cells (which appear as a very homogeneous population of granular lymphocytes) mediate little if any NK activity that could not be augmented by anti-Ti gamma A mAb. In contrast, after initial stimulation by PHA plus rIL-2 and subsequent culture in the presence of IL-2, activated Ti gamma A+ lymphocytes were strongly lytic against a series of conventional NK target cell lines. This cytotoxic function was either blocked or enhanced by anti-Ti gamma A mAb, depending upon experimental conditions. With respect to proliferation, it was possible to induce responses of resting Ti gamma A+ lymphocytes with antibody-coated CNBr beads only in the presence of exogenous IL-2, whereas, in culture, the same cells proliferated directly and secreted IL-2 after treatment by anti-Ti gamma A beads. Taken together, these data demonstrate that a major subset of circulating CD3+ TCR alpha/beta- lymphocytes use protein products of T cell gamma rearranging genes as functional R structures.

Animals↗
PubMed1988

A unique V-J-C-rearranged gene encodes a gamma protein expressed on the majority of CD3+ T cell receptor-alpha/beta- circulating lymphocytes.

We have recently described an mAb, anti-Ti gamma A, that recognizes an antigenic determinant carried by a TCR gamma chain. This antibody binds to approximately 3% of human PBLs and delineates a CD2+, CD3+, TCR-alpha/beta-, CD4-, CD8+/-, CD5+, NKH1-, and HLA class II- subset. The present study was designed to identify the gene encoding the Ti gamma A epitope. A first analysis was carried out on a previously characterized TCR gamma + fetal-cloned cell line termed F6C7. It was found that F6C7 cells have one gamma rearrangement on each chromosome: one joins V gamma 3 to J gamma 1, and the second joins V gamma 9 to J gamma P. Because only the latter allele appeared to be transcribed in the F6C7 lymphocytes, these data strongly suggested that anti-Ti gamma A mAb is specific for either a V gamma 9 or a V gamma 9-J gamma P-encoded peptide. To confirm this point, we studied an additional series of 13 randomly selected Ti gamma A+ cloned cells derived from peripheral blood of three distinct adult individuals. Each one of these lymphocytes was shown to both possess and transcribe a V gamma 9-J gamma P-C gamma 1-rearranged gene. It is therefore concluded that a predominant subpopulation of CD3+ TCR-alpha/beta- human circulating T lymphocytes (namely, the subset defined by anti-Ti gamma A mAb) surface expresses a gamma protein with a limited potential of variability from one cell to another.

Adult↗
PubMed1988

Triggering of the phosphoinositide transduction pathway by a monoclonal antibody specific for the human gamma/delta T cell receptor.

We have developed a monoclonal antibody (mAb), termed anti-TigammaA, which recognizes an antigenic determinant carried by a variable segment of the T cell receptor (TcR) gamma chain. This determinant, encoded by the V gamma 9 gene, is expressed on approximately 3% of peripheral blood lymphocytes. In the present study, we have found that binding of anti-TigammaA mAb to its specific ligand results in the triggering of the phosphatidylinositol (PI) cycle-related metabolic process. Indeed, an increased labeling of both phosphatidic acid and PI, related to an enhanced turnover of PI cycle-dependent phospholipids, was observed following exposure of 32P orthophosphoric acid-labeled cells to anti-TigammaA mAb. In addition, there was a rapid rise in intracellular free calcium concentrations. Similar experiments have been performed previously on CD3+ TcR alpha/beta- -cells with an anti-CD3 mAB. They predicted that signals produced by the interaction between the second TcR and its ligand(s) would be transmitted via the PI cycle-linked intracellular second messengers. We confirm this hypothesis in an experimental system where stimulation occurs directly through the gamma/delta receptor structure.

Antibodies, Monoclonal↗
PubMed1988

Cloned CD3+ TcR alpha/beta- Ti gamma A- peripheral blood lymphocytes compared to the Ti gamma A+ counterparts: structural differences of the gamma/delta receptor and functional heterogeneity.

We have assessed the organization of T cell gamma rearranging genes (TRG) in circulating TcR gamma/delta+ lymphocytes which do not express V gamma 9-encoded Ti gamma A+ gamma chain. Following purification of the minor TcR gamma/delta+ Ti gamma A- fraction, cloned cell lines were developed from peripheral blood of 5 individuals. Out of the 26 clones studied, only 3 TcR gamma/delta+ Ti gamma A- cells were found to express a disulfide-linked C1-encoded gamma chain. The remaining 23 Ti gamma A- clones with a C2-encoded nondisulfide-linked receptor were found to display rearrangements of various V genes to J2 segments on both chromosomes; there was no predominance of a unique rearrangement even though the TRG-V3 and -V4 genes belonging to subgroup I were frequently employed. Together, these findings further strengthen the hypothesis that lymphocytes with a C gamma 1 encoded chain are produced earlier in T cell ontogeny than the C gamma 2 counterparts. The "non-major histocompatibility complex (MHC) requiring" (i.e., "natural killer-like") cytotoxicity mediated by many TcR gamma/delta+ Ti gamma A- cells appeared to be very low as compared to that of Ti gamma A+ clones. Yet, treatment by the OKT3 monoclonal antibody revealed a strong lytic potential in the Ti gamma A- lymphocytes with little, if any, natural killer-like activity. Thus, with respect to the latter function, a substantial heterogeneity is found in cells expressing distinct gamma chains. In an attempt to characterize undefined specificities of Ti gamma A- lymphocytes, they were screened against a panel of Epstein-Barr virus-transformed B cell lines homozygous for HLA-DR1 to DR10 determinants; one of the clones was found to recognize DR7. In light of reports from other groups describing class I-related specificities, it is apparent that TcR gamma/delta+ lymphocytes are able, like the TcR alpha/beta+, to recognize and kill target cells through either an MHC-dependent (with involvement of either class I or class II gene products) or a non-MHC-requiring pathway.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1988

A novel human V delta gene expressed predominantly in the Ti gamma A fraction of gamma/delta+ peripheral lymphocytes.

We have characterized a functional T cell receptor (TcR) delta transcript in a Ti gamma A+ human cloned cell line derived from peripheral blood. This cDNA includes a novel V gene (V-AB12), whose expression was initially studied in a series of TcR gamma/delta+ clones. Nine Ti gamma A+ clones derived independently from distinct donors have been tested: each of them was found to possess a unique V-AB12/J-IDP2 5.5-kb Eco RI rearrangement, which was constantly transcribed. Surface expression of the protein encoded by this unique rearranged gene was demonstrated by immunoprecipitations performed on three Ti gamma A+ polyclonal cell lines using a specific rabbit heteroantiserum. Further analysis strongly suggested that a monoclonal antibody (mAb), designated anti-BB3, detects a V-AB12-encoded antigenic determinant on the cell surface. Double-color immunofluorescence analysis of peripheral blood lymphocytes from ten donors indicated that most BB3+ cells are recognized by anti-Ti gamma A mAb. In previous studies, we have shown that a majority of TcR gamma/delta+ peripheral T cells expresses a gamma chain including V9 (Ti gamma A) and most frequently JP-encoded peptides. Given the present results on the delta chain, it can be concluded that, in many individuals, a predominant fraction (V gamma 9+/V-AB12+) of circulating CD3+ TcR alpha/beta- T lymphocytes expresses a receptor with little, if any, combinatorial diversity.

Amino Acid Sequence↗
PubMed1988

[Artificial urinary sphincter in the treatment of neurogenic bladder in children].

Over a two years period, the model AS 800 artificial urinary sphincter was implanted in 10 children (mean 14 years old) with incontinence due to a neurogenic bladder (7 spina bifida; 3 sacral agenesis). Goal of continence was achieved in 100% of 7 boys and 3 girls with a follow up between 6-32 months (mean 17 months). Patients selection was rigid and incontinence have failed to response at pharmaceutic manipulation (6) intermittent catheterisation (5) and previous classical surgery enterocystoplasty (2), Young-Dees procedure (1). Age minimum was 8 years. All sphincters were implanted around the bladder neck. Associated surgical techniques were performed in 4 cases: 2 detubularized enterocystoplasties, 1 Teflon injection for vesico ureteral reflux, 1 closure of previous cystostomy. Sphincterotomy was never done. 5 patients are submitted post implantation to intermittent catheterisation without any problem. 2 patients required one revision. Nocturnal desactivation is used in 2 cases. Authors focus on the necessity of correcting previously or at the time of implantation bladder compliance and vesico ureteral reflux.

Adolescent↗
PubMed1988

[Magnetic resonance imaging of high anorectal malformations. A preliminary study apropos of 15 cases].

High level ano-rectal anomalies were evaluated by Magnetic Resonance Imaging (MRI) in 15 patients. One neonate and two infants were evaluated preoperatively. Sagittal slices identified properly the blind rectal end in the 3 cases. Associated anomalies (tethered spinal cord, right ectopic kidney in 1 case, recto-urinary fistula in another case, upper excretory dilatation in 2 cases) were found during the same examination. In the post-operative period (12 cases), major data were obtained on axial transverse slices. When pulled-through intestine is outside the levator sling, re-do-surgery can be indicated. MRI appears as an accurate tool to assess these anomalies.

Adolescent↗
PubMed1987

A novel subset of human lymphocytes with a T cell receptor-gamma complex.

We have previously characterized a CD3+ T cell receptor (TCR) alpha/beta- human fetal cloned cell line, termed F6C7, which surface-expresses a CD3-associated gamma chain identified by anti-NKFi, an mAb with a restricted clonotypic reactivity. Here, we have produced an additional antibody, anti-Ti-gamma A, which recognizes a public epitope of the gamma molecule defined by anti-NKFi. Ti-gamma A is present on approximately 3% of circulating lymphocytes with a wide range (1-15%) among 30 healthy individuals tested. Two-color immunofluorescence experiments performed with anti-Ti-gamma A and BMA 031 mAb (a reagent specific for the TCR-alpha/beta receptor) showed that surface expression of Ti-alpha/beta and Ti-gamma A is mutually exclusive. Moreover, it was found that most Ti-gamma A+ cells are CD2+, CD3+, CD4-, CD5+, NKH1-, HLA class II-negative. In contrast, the expression of the CD8 molecule on these T lymphocytes appears to be variable from one individual to another. Finally, we found that Ti-gamma A+ cells represent a majority of peripheral lymphocytes that express CD3 proteins but not the TCR-alpha/beta heterodimer. The delineation of this unique lymphocyte subset should help further studies on the biology of cells with a CD3-associated gamma complex.

Animals↗
PubMed1987

Cloned human CD3- lymphocytes with natural killer-like activity do not express nor rearrange T cell receptor gamma genes.

Here we report the characterization of T cell receptor (TCR) gene activation in 14 CD3- cloned lymphocytes with natural killer-like activity from different origins. No transcription of either alpha or beta or gamma genes is detected in any of these clones. All J beta, C beta clusters are in germ-line configuration. The 5 presently described J gamma loci (J gamma P1, J gamma P, J gamma 1, J gamma P2, J gamma 2) are also in germ-line configuration on each chromosome. These results indicate that several distinct populations of CD3- cloned NK cells do not use gamma gene products as a recognition structure. Perhaps more importantly, these cells do not appear to be engaged in the earliest presently known stage of T lymphocyte differentiation, namely rearrangement at one of the J gamma loci.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1986

Natural killer clones derived from fetal (25 wk) blood. Probing the human T cell receptor with WT31 monoclonal antibody.

We have conducted a phenotypic and functional analysis of 19 cloned cell lines generated after allogeneic stimulation of circulating lymphocytes from a normal human fetus aged 25 wk. Using a limited series of mAbs (Anti-T3, WT31, T4, T8, and NKH1A), cloned cells were found to fall in three groups. Three clones have a conventional "inducer" phenotype. Three clones have a phenotype (T3+, WT31+, T8+, and NKH1A+) similar to that of certain NK active mature T lymphocytes present in adult peripheral blood. In contrast, 13 cell lines display surface characteristics that have not been described previously. Indeed, they express T3 proteins but not the WT31 determinant. In light of previous studies, these results show that WT31 mAb is a unique reagent directed at an invariant epitope of the human T cell receptor that is not present on all circulating T3+ fetal lymphocytes. Functionally the T3+, WT31+, and NKH1A+ clones were found to kill immunizing LAZ 388 cells, as well as K562, while T3+, WT31- and NKH1A+ clones display NK-like function exclusively. Moreover, only WT31+ lymphocytes present in the cell line used for cloning experiments have the capacity to recognize alloantigen-bearing cells. Together, these data suggest that expression of WT31 may be necessary for recognition of alloantigens, while NK reactions mediated by T3+ lymphocytes are WT31-independent.

Animals↗
PubMed1986

Noninvasive fluorine-19 NMR study of fluoropyrimidine metabolism in cell cultures of human pancreatic and colon adenocarcinoma.

Fluorine-19 NMR spectrometry was used to monitor the metabolism of two antineoplastic fluoropyrimidines, 5-fluorouracil (5FU) and 5'-deoxy-5-fluorouridine (5'dFUrd), in cell cultures of human pancreatic (Capan-1) and colon (HT-29) adenocarcinoma. The preliminary results showed, for the two tumor cell lines treated with 5FU, the presence in nonperfused cells of three signals corresponding to intracellular metabolites: 5FU, F-nucleotides and F-nucleosides. When the cells were perfused only the signals of F-nucleotides and 5FU were present. The F-nucleosides observed during the analysis of the nonperfused cells came from the conversion of F-nucleotides. During the NMR recording of Capan-1 cells at 37 degrees C the first metabolite of the catabolic pathway of 5FU, 5,6-dihydro-5-fluorouracil, occurred. At the beginning of the NMR recording of Capan-1 cells treated with 5'dFUrd, two signals corresponding to F-nucleotides and F-nucleosides (consistent with 5'dFUrd) were observed; during the analysis, a supplementary signal corresponding to 5FU appeared. Even after pretreatment with methotrexate the signal of 5FU incorporated into RNA was not detected. Our experiments, performed in attempts to observe the signal of the ternary complex between thymidylate synthetase (TS), 5-fluoro-2'-deoxyuridine-5'-monophosphate (FdUMP) and 5,10-methylene-tetrahydrofolate (5,10-CH2FH4), allowed detection in some cases of a broad signal, whose chemical shift was similar to that reported in the literature following incubation of TS with FdUMP and 5,10-CH2FH4, but our results were not always reproducible.

Adenocarcinoma↗
PubMed1986

[Digitalized angiography of the thorax in children].

Technical aspects and indications for the use of digital subtraction angiography of thorax in 109 children are discussed, and the interest of this exploratory method emphasized in chronic respiratory disease in children. Results obtained are compared with other investigations for screening of bronchopulmonary dysplasia. Although generally reliable for exploration of thoracic aorta anomalies (coarctation and abnormal vascular arch) it is considered to be incompletely effective for investigation of congenital heart disease.

Acute Disease↗
PubMed1986

[Echographic aspects of candidiasis of the urinary tract in infants. Apropos of 2 cases].

Predisposing factors in two children with urinary tract candidiasis included: neonatal period, uropathy with malformation, massive antibiotic therapy. Ultrasound images showed dilated excretory cavities of variable echo intensities and without posterior shadow cone. Diagnosis was confirmed by urine culture and a satisfactory outcome obtained by specific therapy and surgery for malformations.

Candidiasis↗
PubMed1986

[Enterocystoplasty in the treatment of neurological bladders. Can the results be improved?].

Over a period of 3 years. 10 cases of enterocystoplasties have been done in congenital neurologic bladder in children. Seven patients have been operated using sigmoide (6), caecum (1) in their tubular form. In the last 3 cases sigmoide was used as a patch without any resection of the bladder. Post-operative urodynamic testings were better with sigmoide patch. The authors pointed out this technique.

Adolescent↗
PubMed1985

Tn7-encoded proteins.

Proteins encoded by Tn7 have been studied in Escherichia coli maxicells harbouring either various deleted ColE1::Tn7 plasmids or Tn7 fragments cloned in pBR322. Six Tn7-encoded proteins were detected and named p18, p32, p40, p54, p85-a and p85-b according to their apparent molecular weight. Protein p18 is dihydrofolate reductase type I and p32 is probably the protein conferring resistance to streptomycin/spectinomycin. Both genes map on the left-hand part of Tn7. The genes for the four other proteins are located on the right-hand part of Tn7. We propose that they fully cover a 6.9 kb DNA fragment without any overlapping. Starting from the right-hand end towards the middle of the transposon, these four genes are in the following order: p85-a, p54, p40 and p85-b. Transposition of Tn7 onto E. coli plasmids requires the proteins p85-a, p85-b, p54 and p40. However, transposition onto the chromosome does not require the p85-b and p40 products.

Bacterial Proteins↗
PubMed1985

[Striated and delayed nephrography].

About a case of striated and delayed nephrogram seen on a diabetic child, authors come back to the different etiologies. Among them, the tubular precipitation of Tamm-Horsfall protein seems to be given like on the right possibilities. Whatever is its etiology, the mechanism of striated appearance is always the same, being founded on the radiated disposal of the collecting ducts and on a tubular stasis beeing with iodine concentration.

Adolescent↗
PubMed1984

Pseudotumoral cecum after hydrostatic reduction of intussusception.

The authors report two cases of intestinal intussusception successfully reduced by hydrostatic pressure. A post-reduction filling defect in the cecum disappeared spontaneously on follow-up barium enema, and is therefore consistent with cecal edema. It appears an initial period of close observation for such cases is worthwhile, delaying the decision about surgery until after a follow-up barium enema; this may confirm the disappearance of the filling defect.

Barium Sulfate↗