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Biomedical subjects

R Maunoury

Publications and source records attributed to R Maunoury.

At least 37 records · Page 2Linked to original sources
PubMed1985

Evidence that mouse astrocytes may be derived from the radial glia. An immunohistochemical study of the cerebellum in the normal and reeler mouse.

Astrocytic cells of unusual aspect can be detected in the cerebellum of normal mice during the first 4 weeks of life. They are visualized with anti-GFAP (glial fibrillary acidic protein), anti-S100 and anti-vimentin immune sera. Their perikaryons, located in the white matter or in the granular layer, extend long processes which are inserted onto the pial surface. These cells may be transitional forms between the radial glial cells and some of the differentiated astroglial elements. These unusual astrocytes are more numerous and heavily stained in the reeler mutant than in the normal mouse and it is suggested that our observations signify some degree of glial immaturity in the cerebellum of the mutant.

Animals↗
PubMed1985

[Simultaneous immunocytochemical demonstration of the centrosphere and nucleolar organizer in cultured human cells].

A rabbit showing natural centrosphere-immunoreactivity was immunized with streptococcus pyogenes type 24 (S 24). During the immunization, an additional NOR-immunoreactivity appeared. This reactivity was not inhibited after the serum absorption by S 24 and seems fortuitous. The simultaneous immunoperoxidase technique staining centrosphere and NOR is described and illustrated during successive phases of mitosis. Unique as of this date, this serum may serve as a useful tool to study the centrosphere and NOR.

Animals↗
PubMed1984

SV40 immortalization of adult human mesenchymal cells from neuroretina. Biological, functional and molecular characterization.

Human adult mesenchymal cells from neuroretina (human choroid cells, HC) have acquired an infinite lifespan, following phenotypic transformation with a wild-type SV40. Immortalized cells (HC/SV40) contain high numbers of free circular viral DNA, and integrated molecules in a head-to-tail array in the cellular DNA. HC/SV40 cells express both the virus-coded "T" antigens and the cell-coded p53 transformation-associated protein. The transformed phenotype was further characterized by loss of contact inhibition of cell division, inability to induce the retraction of a fibrin clot and to spread within fibrin, and the existence of an altered distribution of actin cables. For the first time we also describe a coupling of the immunofluorescence and the quantitative cytofluorometric analyses, a new transformation parameter, since we show that SV40 transformation causes reorganization of the cell membrane by inducing the unmasking of the antigen recognized by the 4F2 monoclonal antibody, which is present in a "cryptic" form in the untransformed cells. Though the HC/SV40 cells have been continuously passaged over a 3-year period, they have not yet achieved a fully malignant phenotype, since they retain serum-dependency and the presence of a well developed fibronectin pericellular network, and they are not tumorigenic in nude mice. Thus this human immortal cell line constitutes a very useful tool for studying the progression toward full malignancy and the relationships between evolution of transformation parameters and changes in the viral and cellular genome interplay.

Adult↗
PubMed1984

[Demonstration of plasmacytes in gingival immune defense units in dermoid cysts of the ovary].

Gingival units of immunological defense have been observed surrounding erupted teeth in the connective tissue of the wall of ovarian dermoid cysts. Using a modified immunoperoxidase technique, the production of IgA, IgG and J chains has been clearly detected. This technique works perfectly on decalcified specimens. Since dermoid cysts are not contaminated, the origin of the plasma-cells in these units is presumed to be triggered by other antigenic factors. These are present in epithelium and provided a possible explanation for the "homing" of lymph-cells migrating from the immune system.

Dermoid Cyst↗
PubMed1984

[Production of monoclonal antibodies against gliofibrillary acid protein (GFAP) and their specificity].

Splenic Mice cells immunized with glial fibrillary acidic protein (GFAP) were fused with SP 2/0 myeloma cells. After screening and cloning we obtained two types of hybridomas. Some of them secrete IgG class antibodies, the others IgM class antibodies. The specificity of these antibodies has been tested by three immunoenzymatic methods. The results are that IgG monoclonal antibodies identify an astrocyte-GFAP specific epitope and IgM monoclonal antibodies cross-react with a common epitope to GFAP and vimentin.

Animals↗
PubMed1983

Heat as a probe of centrosomal function: a phase-contrast and immunofluorescent study of human blood monocytes.

In normal human blood monocytes, the nucleus is indented by the centrosome, which excludes the phase-dense granules that are spread throughout the cytoplasm. Within this paranuclear region, the paired centrioles are marked by immunofluorescent staining with an anti-centrosome antibody directed against the pericentriolar osmiophilic material that appears to serve as microtubule-organizing centers (MTOCs). Congruent paired structures are seen in phase-contrast. Following heat treatment (45 degrees C, 9 min), granules are retracted about a less indented nucleus, and anti-centrosome immunofluorescence is absent or very weak, even though paired centrosomal structures remain at least as phase-dense as in controls. Immunofluorescent staining with antimicrotubule antibody is also essentially lost following heat treatment. These findings are consistent with a heat-induced lesion in the pericentriolar osmiophilic material, which may prove generally useful as a probe of centrosomal function.

Centrioles↗
PubMed1982

[Immunohistochemical localization of the associated proteins of high molecular weight (HMWP 350 K, 300 K) in the nervous system of the rat (author's transl)].

High molecular weight microtubule-associated proteins (HMWP) were localized by immunoperoxidase PAP method in Rat nervous system. With tissue sections obtained after alcohol-acid fixation and embedding in paraffin we have observed that: (1) at low antibody concentrations (5 to 10 micrograms/ml) the staining was specific for the central nervous system (CNS) and the peripheral nervous system (PNS); (2) the staining was found in the neurons of the cerebrospinal axis, of the eye, of the paravertebral chains of the sympathetic system, of the plexuses juxta and intra visceral and also in the cells of the adrenal medulla; (3) the dendrites and the pericaryon are the most stained elements of the CNS and PNS respectively; (4) the HMWP are colocalized with tubulin but the reverse is not the case.

Animals↗
PubMed1982

[In vitro modification of the morphology and the growth of cells infected with scrapie (author's transl)].

Seven cell lines originated either in brains or in neuroblastomas of Mice, were infected with Scrapie. After 12 to 16 in vitro passages, 6 lines out of 7 showed changes of their morphology, and of their growth, resembling those occurring in the course of a malignant transformation. The Scrapie infected cells acquired the capacity to form 2 to 4 times more colonies in liquid medium than the controls, and to develop large tridimensional colonies in semisolid medium. The role of Scrapie in these changes is discussed.

Animals↗
PubMed1981

[Immunoelectron microscopic localization of the centriolar zone in cultured human cells].

Centriolar area of human cells in culture was stained and observed by coupling immunoperoxidase technique and the use of Rabbit natural antibody. This staining showed a component which appears mainly as granular pericentriolar muffs in continuity with lateral projections similar to the satellites which have been described in conventional electron microscopy.

Cells, Cultured↗
PubMed1980

[Immunocytochemical localization in human spermatozoa of tubulin and the associated high molecular weight proteins MAP1 and MAP2].

By immunofluorescent and immunoperoxidase techniques and with the use of highly purified antibodies, tubulin and its associated proteins, MAP1 and MAP2 have been identified and precisely localized in human spermatozoa. In relation to well known structural elements, tubulin appeared localized to the region of the axoneme, the centriolar adjunct and the equatorial part of the acrosome, in contrast MAP1 and MAP2 were localized to the post-nuclear region and in the fibrous sheath of the principal piece of the flagella.

Cell Nucleus↗
PubMed1979

Normal and benzo(a)pyrene-transformed fetal mouse brain cell. I. Tumorigenicity and immunochemical detection of glial fibrillary acidic protein.

Primary cultures of whole brain and cortex cells origination from 14-day-old A/Jax or C3H mouse fetuses were treated with benzo(a)pyrene (B(a)P) for 24 h. After 7 to 8 passages a malignant transformation was observed in the chemically treated whole brain and cortex cultures. Control cultures of cortex remained non-transplantable during the whole experiment (up to 14 passages) whereas in the control cultures originating from whole brain a spontaneous transformation appeared after 11 passages. With horseradish peroxidase-labelled antibody, the specific glial fibrillary acidic protein (GFAP) was detected in both control and transformed total brain and cortex cultures, and in the tumors initiated by the in vitro transformed cells. This finding shows that glialike cells persisted after a long in vitro maintanance and transformation.

Animals↗
PubMed1979

[Spontaneous transformation and long term culture of foetal mouse glial cells (author's transl)].

Six cell lines originated from foetal mouse brain were maintained in vitro for more than two years. The morphology of most of these cultures suggests their glial character. This is corroborated, for some lines, by the presence of specific glial protein (Glial fibrillary acidic protein, or GFAP). Five out of these lines remained not transplantable in animals during all the experiments. However one of them went through a spontaneous transformation at the eleventh population doubling. This culture, after transformation remained glial and when injected in animals, induced GFAP containing tumors.

Animals↗
PubMed1979

[Psychoses, immunity and neurospecific antigens. Current knowledge and perspectives].

Investigations performed by various workers during the last ten years suggest that some forms of mental illness are associated with a variety of immunological reactions. Significant variations in immunoglobulin ratios have been observed in patients with psychotic illness, and cellular and humoral cytotoxic activities against cerebral tissue have been demonstrated in vitro. At the molecular level, several subjects can be proposed for investigation into immunological phenomena in neuropathology. Thus, the neurospecific antigens, which have been isolated by biochemical methods, but the physiological role of which is largely unknown, open news ways to the experimental exploration of psychopathology.

Brain↗
PubMed1978

[Trials of mixed grafts of 5 cell lines from human brain tumors in athymic nude mice].

Five established lines derived from human brain tumors were mixed in pairs and injected into athymic nude Mice. The observation of mixed tumors and patterns of rejection obtained after inoculation enabled us to classify these five lines according to their aggressiveness in a heterologous host. In addition, the SA 52 line induced an inhibitory effect on graft growth (or a facilitation of rejection).

Adenocarcinoma↗