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B Mely-Goubert

Publications and source records attributed to B Mely-Goubert.

6 recordsLinked to original sources
PubMed1992

Fluorescent staining of the actin cytoskeleton in human lymphocytes, monocytes and polymorphonuclear cells using a DNAse 1/anti-DNAse 1 immunoglobulin fluorescein conjugated system.

The actin associated with membrane-enriched extracts of leukocytes can be quantitated by DNAse 1 inhibition. Using this assay, we previously demonstrated that the actin level in monocytes was significantly higher than that in polymorphonuclear, T and B cells respectively. However, the extracellular location of the actin fraction detected by DNAse 1 inhibition (monomeric "G") remained unclear. This study using the DNAse 1/anti DNAse 1 immunoglobulin fluorescein conjugated system demonstrated that G-actin is present primarily in the cortical cell cytoplasm of leukocytes, in confirmation of our previous biochemical findings. Since the solubilized G-actin activities of membrane-rich lymphoid cell fractions, measured by DNAse 1 inhibition, are a reflection of the migratory potential, this immunofluorescent system may permit identification of the leukocytic cell subpopulations that have a potential for active circulation.

Actins↗
PubMed1988

Cell surface energy and membrane associated actin in lymphocytes.

We have shown previously that membrane associated actin correlates with the migratory abilities of lymphocytes during recirculation, and that cell surface energy correlates with the adhesiveness of lymphocytes to other cells. In this study, measurements of actin content and cell surface energy have been made for various lymphocyte subpopulations to examine the possibility that recirculation ability may be related to nonspecific adhesiveness. We have found that: both cell surface energy and actin content combine to provide a consistent explanation for the relative rates of recirculation of various lymphocyte subpopulations, and cell surface energies and actin contents vary independently in these lymphocyte subpopulations. Comparison of the actin contents and cell surface energies of metastatic and nonmetastatic lymphoma cell lines indicated that the differences in metastatic potential were more likely attributable to specific receptor-ligand interactions than to nonspecific adhesiveness. Cell surface energy and actin content are consistent with the greater adhesiveness of B cells than T cells to nylon wool, providing a physical basis for this common cell separation technique.

Actins↗
PubMed1988

Polymerized actin in lymphoid cells: functional interpretation.

Nitrobenzoxadiazol (NBD) phallacidin, an active fluorescent derivative of the actin-binding mushroom toxin phallacidin provides a convenient actin-specific fluorescent label for cellular cytoskeleton structures. Topographical fluorescent microscopy images of lymphoid cells obtained with NBD-phallacidin staining reveal that the major feature of the cellular cytoskeleton characterized by actin are mainly associated with cell membrane, a pattern that correlates strikingly with their DNAse 1 inhibition. Such actin pools may thus be involved in a membrane-associated protein network controlling membrane viscoplastic deformation and cell motility.

Actins↗
PubMed1983

Distribution of actin content in human B and T lymphocytes by DNAse 1 inhibition test.

The DNAse inhibition assay, which allows for the titration of two forms of soluble actin in cell extracts, has been applied to normal human lymphocytes from peripheral blood. Actin-like activities associated with the membrane-rich fraction of extracts from thymus dependent (T) lymphocytes are significantly higher than those from bone marrow derived (B) lymphocytes, on a per cell basis, provided care is paid to the elimination of monocytic and polymorphonuclear cells which produce significantly higher DNAse 1 inhibition. The apparent discrepancy with a recent report that normal T and B lymphocytes do not differ in their total actin content is discussed with respect to the functional uniqueness of membrane-associated DNAse 1 inhibitions and the importance of using purified lymphocyte populations.

Actins↗
PubMed1981

Actin content in lymphocytes: a proposed correlation with their recirculating properties.

The DNAase inhibition assay, which allows for the titration of monomeric and total actin content per cell, has been applied to various subpopulations of rat lymphocytes. We found that characteristic values are associated with functionally distinct subpopulations. Thus, thymus-dependent (T) lymphocytes have significantly higher monomeric and total actin per cell than bone marrow-derived (B) lymphocytes, irrespective of the separation procedure used (in vitro or in vivo). Moreover, these values appear to increase with the differentiation state of the cells within the T compartment (i.e., from thymus to lymph node to thoracic duct lymphocytes). The fact that the observed trends overlap the known in vivo recirculating abilities of the populations tested prompted us to discuss the possible involvement of intracellular actin in the control of the cell-surface deformability.

Actins↗