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Biomedical subjects

M Sarmiento

Publications and source records attributed to M Sarmiento.

47 records · Page 3Linked to original sources
PubMed1980

Cell surface polypeptides of murine T-cell clones expressing cytolytic or amplifier activity.

Murine cytolytic T-cell and amplifier T-cell clones derived from secondary unidirectional mixed leukocyte cultures were labeled with 125I by the lactoperoxidase method and their polypeptide profiles were analyzed by NaDodSO4/polyacrylamide gel electrophoresis. All cytolytic T-cell clones derived from the same mouse strain yeilded similar cell surface polypeptide profiles. However, profiles obtained with three amplifier T-cell clones were strikingly different from each other as well as from those of cytolytic T-cell clones. Comparison of these profiles with those obtained from mixed leukocyte culture cells, whole spleen cells, glass wool/nylon wool-purified splenic T-cells, and thymocytes indicates that cytolytic T-cell clones have a characteristic cell surface polypeptide profile that distinguishes this type of lymphocyte from most other lymphocytes.

Antigens, Surface↗
PubMed1980

IgG or IgM monoclonal antibodies reactive with different determinants on the molecular complex bearing Lyt 2 antigen block T cell-mediated cytolysis in the absence of complement.

Five rat monoclonal antibodies have been derived that express specificities for determinants present on the molecular complex bearing the Lyt 2 antigen. SDS-polyacrylamide gel electrophoresis of 125I-labeled polypeptides precipitated by each of these antibodies reveal 3 components (150,000, 75,000, and 33,000 daltons), and 2 components (44,000 and 33,000 daltons) when analyzed under nonreducing and reducing conditions, respectively. Two of these antibodies are IgG and are specific for the Lyt 2.2 determinant; the other 3 are IgM and react with determinants other than Lyt 2.2, which are nonpolymorphic. Each of the 5 antibodies can block the cytolytic activities of 5-day MLC cells or of cloned cytolytic T cells in the absence of C. Treatment of responding spleen cells with any of these antibodies and C inhibits the generation of cytolytic activity in MLC.

Animals↗
PubMed1979

Membrane proteins specified by herpes simplex viruses. III. Role of glycoprotein VP7(B2) in virion infectivity.

Experiments done with a temperature"sensitive mutant of herpes simplex virus type 1 (HSV-1) have revealed that one of the virisn glycoproteins, designated VP7(B2), is apparently not required for the production of enveloped virus particles, whereas it does play a critical role in virion infectivity. The mutant, designated HSV-1[HFEM]tsB5, fails to accumulate VP7(B2) at nonpermissive temperature and produces virions that lack detectable quantities of this glycoprotein and that have very low specific infectivity. The poor infectivity of the virions is most readily explained by failure of penetration into the host cell rather than by failure of adsorption to cells because it was shown that the VP7(B2)-deficient virions can bind to cells and that polyethylene glycol, an agent known to promote membrane fusion, can significantly enhance infectivity of the adsorbed virions.

Absorption↗
PubMed1979

Membrane proteins specified by herpes simplex viruses. IV. Conformation of the virion glycoprotein designated VP7(B2).

The herpes simplex virus glycoprotein designated VP7(B2) is extracted from virions by nonionic detergent in the form of an oligomer, whereas the other detergent-soluble envelope proteins appear to be extracted as monomers. The subunits of the VP7(B2) oligomer cannot be dissociated by 2-mercaptoethanol and are also resistant to dissociation by a mixture of sodium dodecyl sulfate and 2-mercaptoethanol, except at elevated temperature. The oligomeric form of solubilized VP7(B2) appears to be predominantly dimeric, based on the sedimentation rats in sucrose gradients and the electrophoretic mobilities in sodium dodecyl sulfate-containing acrylamide gels of the undissociated and heat-dissociated forms of VP7(B2).

Glycoproteins↗
PubMed1978

The structural proteins and glycoproteins of herpesviruses: a review.

The virions of different herpesviruses are similar with respect to the number and kinds of constituent polypeptides, in spite of variability in the structures of individual polypeptides. The total number of virion polypeptides and glycopeptides ranges from 20 to 30 for different viruses and, in general, no more than one-quarter of these polypeptides is detectable in naked nucleocapsids, implying that most of the virion polypeptides are acquired during the process of envelopment. Although the functions of most individual structural proteins have not been identified, one can predict that the nucleocapsid proteins serve primarily structural roles or may mediate packaging of the viral genome, that the non-glycosylated envelope proteins play essential roles in the process of envelopment and that the glycoproteins, which are probably all exposed to the virion surface, mediate adsorption to and penetration of the host cell. Two of the herpes simplex virus glycoproteins have been identified as targets of neutralizing antibodies and one of these proteins has been shown to mediate viral penetration, probably by promoting fusion between the virion envelope and cell surface membrane.

Capsid↗
PubMed1975

Comparison of the virion proteins specified by herpes simplex virus types 1 and 2.

Purified herpes simplex virus type 2 (HSV-2) virions were found to contain approximately the same number of polypeptides as HSV type 1 (HSV-1) virions. Comparisons of the structural proteins specified by five independent HSV-2 isolates revealed some minor differences in their electrophoretic profiles on sodium dodecyl sulfate-acrylamide gels; certain invariant features of the electrophoretic profiles, however, allowed clear differentiation between all the HSV-2 isolates and HSV-1.

Electrophoresis, Polyacrylamide Gel↗