Biomedical subjects

C Grief

Publications and source records attributed to C Grief.

4 recordsLinked to original sources

PubMed1991

Antiviral properties of Ro 31-8959, an inhibitor of human immunodeficiency virus (HIV) proteinase.

Ro 31-8959 inhibits the spread of HIV infection and the production of cytopathic effects in cultures of acutely infected cells. IC50 values for these effects are in the range 0.5-6.0 nM and IC90 values are in the range 6.0-30.0 nM. This inhibitor is effective even when added to cultures at a late stage of infection, after syncytia have started to form. Virus antigen, virus particles and virus cytopathic effects can largely be cleared from cultures treated with compound from 3 days until 6 days post infection. In chronically-infected cells, inhibition of virus maturation can be detected after 24 hours' treatment with 10 nM Ro 31-8959. In addition, a significant reduction of the proteolytic processing of p56 to p24 can be demonstrated in these cells with compound at picomolar concentrations. These properties indicate that Ro 31-8959 is highly effective against HIV with the potential to inhibit acute, established acute and chronic infections.

Antiviral Agents↗

PubMed1991

The assembly of HIV within the Golgi apparatus and Golgi-derived vesicles of JM cell syncytia.

Chronic infection of the T-lymphocyte cell line JM with HIV-1 isolate GB8 results in the formation of multinucleate cells (syncytia). Transmission electron microscopy of these syncytia showed the presence of HIV particles both at the cell surface and within cytoplasmic vesicles. HIV particles were observed in dilated Golgi cisternae and Golgi-derived vesicles and in large vacuoles near the periphery of the syncytia. Immunolabelling was performed using an affinity-purified antiserum to the Golgi enzyme galactosyltransferase. This enzyme was consistently localized within both the Golgi apparatus and within virus-containing vesicles of JM syncytia, indicating that these vesicles originated from the Golgi apparatus.

CD4-Positive T-Lymphocytes↗

PubMed1989

The morphology of simian immunodeficiency virus as shown by negative staining electron microscopy.

Negative staining electron microscopy was used to study sucrose gradient-purified preparations of the simian immunodeficiency virus (SIVmac251). Both isolated and aggregated virus particles were observed together with some free-lying virus cores. The cores were 110 nm long and 25 to 50 nm wide and were mainly conical or wedge-like in shape. Surface projections were seen on the envelope membrane of many of the virus particles; the knobs were approximately 6 nm in length, 10 nm wide and from an end-on view they had a Y or triangular-shaped morphology.

Centrifugation, Density Gradient↗

PubMed1985

Cell wall glycoproteins: structure and function.

Hydroxyproline-rich glycoproteins form an important, but little understood, structural component of most cell walls. Their occurrence, chemistry, synthesis, secretion, cross-linking and functions in higher plant cell walls will be briefly reviewed. Similar molecules also occur in other groups of plants; in particular, in the algae. In many of these they form highly ordered cell surface arrays, and we have studied these by high-resolution electron microscopy and computer image reconstruction. Some resulting three-dimensional models of these are presented. One particular glycoprotein, the major structural component of the cell wall of Chlamydomonas reinhardii, has been investigated in some detail. The chemistry and structure of this glycoprotein, which we have called volvin, has been studied and a family of monoclonal antibodies has been raised against it. Some of these antibodies appear to be specific to oligosaccharide side-chains and allow the localization of these substituents and their sites of synthesis. Immunofluorescence studies have shown that the expression of some of these antigenic determinants is developmentally regulated or cell-cycle-dependent. Immunogold labelling of thin sections has enabled the sites of synthesis and the method of secretion to be determined. These results will be discussed in the context of other cell wall glycoproteins, their relation to other glycoproteins, such as the mating agglutinin, and to their possible functions.

Cell Wall↗