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W J Grimes

Publications and source records attributed to W J Grimes.

At least 37 records · Page 2Linked to original sources
PubMed1982

Heterogeneity of asparagine-linked oligosaccharides of five glycosylation sites on immunoglobulin M heavy chain from mineral oil plasmacytoma 104E.

Mouse myeloma immunoglobulin IgM heavy chains were cleaved with cyanogen bromide into nine peptide fragments, four of which contain asparagine-linked sites of glycosylation. Three of these glycopeptides contain a single site located at asparagines 171, 403, and 563 in the sequence of the intact heavy chain. Another glycopeptide contains two sites of glycosylation at asparagines 332 and 364. All sites contain multiple oligosaccharide structures with a trend towards increased processing from the COOH to the NH2 terminus. Structures present at asparagine 563, located only exclusively high mannose oligosaccharides. Asparagine 403, located penultimate to the COOH terminus, has a major component that is of a complex nature but is incompletely processed. Other sites contain predominantly complex structures consisting of biantennary or triantennary branches. The unusual structure found at asparagine 403 contains fucose even though only one branch has been processed to a terminal galactose. These studies suggest that each site has a unique set of heterogeneous oligosaccharides derived from a complex processing system which utilizes a combination of "position completeness" and polypeptide structure to determine final carbohydrate structure.

Amino Acid Sequence↗
PubMed1979

Two-dimensional electrophoresis of membrane proteins from normal and transformed cells.

We have compared cell surface proteins and glycoproteins from normal and transformed cells by two-dimensional electrophoresis. The tumor lines studied include viral and spontaneous transformants which cause tumors that either regress, or grow progressively and kill the host. After the cells were labeled, crude membranes were prepared, and their protein components were resolved by two-dimensional electrophoresis. Cells were labeled with either [35S]methionine, [14C]glucosamine, or 125I-lactoperoxidase. This allows comparison of cell-cell differences in surface structure as well as membrane proteins and glycoproteins. We have demonstrated that not all transformed cell lines give a characteristic "transformed" protein pattern. Many of the differences between the normal and transformed cell protein patterns may be related to alterations in the carbohydrate of membrane glycoproteins. A correlation can be made between the patterns obtained for cell lines and the immunogenicity and tumorigenicity of these cells in vivo.

Animals↗
PubMed1978

Isolation and characterization of a tumor cell surface antigen from spontaneously transformed BALB/c mouse fibroblasts.

This work describes the detection, isolation, and partial characterization of a BALB/c mouse fibroblast cell surface antigen. This antigen migrates as a polypeptide of approximately 100,000 daltons in a discontinuous sodium dodecyl sulfate/polyacrylamide gel electrophoresis system, can be labeled by either lactoperoxidase-catalyzed cell surface 125I iodination or metabolic incorporation of [3H]glucosamine, and can be isolated by concanavalin A affinity chromatography. This cell surface glycoprotein is antigenic in BALB/c mice and has been correlated with the rejection of immunogenic tumor cells. Also, antiserum specific for Moloney leukemia virus precipitates the 100,000-dalton cell surface protein from viral and immunogenic spontaneous transformants. This virus-related antigen comigrates on sodium dodecyl sulfate gels with the major iodinated cell surface protein of these transformants. Rabbit antiserum to the purified antigen demonstrates a marked preference for the surfaces of immunogenic tumor cells as compared with normal cells and nonimmunogenic tumor cells.

Animals↗
PubMed1977

A comparison of membrane components of normal and transformed BALB/c cells.

Membrane glycolipids, glycoproteins, and surface proteins of normal and transformed BALB/c cell lines have been compared. Several virally and spontaneously transformed cell lines showed differences in membrane components compared to normal A31 cells. These differences consisted of increased amounts of simpler gangliosides, absence of the large external transformation sensitive (LETS) protein, and the appearance of a major new glycoprotein band of about 105 000 molecular weight. In contrast, the spontaneously transformed cell line that caused the fastest growing tumors in vivo and the most rapid animal death (3T12T) did not have these changes. A31 and 3T12T glycolipid profiles appear similar as did glycoproteins and cell surface proteins detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. When Pronase-generated glycopeptides were analyzed by Sephadex G-50 chromatography, and enrichment in faster-eluting species was seen in two killing tumor lines (c5T and 3T12T) compared to A31. Regressing tumor lines (MSC, c5) did not show this change. Isolated membrane glycoproteins yield glycopeptides of different sized after Pronase digestion. In addition, several 3T12T glycoproteins yield glycopeptides that are larger than those from the corresponding glycoproteins of A31 cells. It appears that glycopeptide alterations associated with transformation occur in several membrane glycoproteins.

Animals↗
PubMed1977

Chemical and immunological studies of cell surfaces from normal and transformed cells.

Immunological and chemical studies of cell surfaces from normal and transformed BALB/c fibroblasts have shown alterations associated with transformation. The cells studied include normal lines which do not cause tumors when injected into BALB/c mice, viral transformants, and spontaneous transformants which cause tumors that either regress or grow progressively, killing the host. The spontaneously transformed progressors include cell lines which are immunogenic and nonimmunogenic as determined by the ability of tumor excision to protect an animal from subsequent rechallenge by tumor cells. Tumor-bearing mice produce lymphocytes which are nonspecifically cytotoxic for all the normal and transformed lines. Some of the cell lines induce specific antibody formation in BALB/hosts. Antisera have been prepared in rabbits which are specific for the transformed cell lines. These antisera can be used to determine specific surface changes on the transformed cells. Chemical studies have shown glycolipid alterations between the normal cells and some, but not all, of the transformants. Glycoproteins labeled by lactoperoxidase-125I or [3H] glucosamine were compared by SDS gel electrophoresis. Results from these studies do not show changes associated with malignancy. Individual glycoprotein regions from gels were treated with pronase, and the glycopeptides compared by Sephadex G50 chromatography. Alterations in glycopeptides from several cellular glycoproteins are the only changes which appear to be associated with malignancy.

Animals↗
PubMed1976

Formation of mannosyl-lipids by an ectomannosyltransferase in suspensions of BALB/c fibroblasts.

A mannosyltransferase has been detected in suspensions of BALB/c fibroblasts incubated with GDP-[14C] mannose. The experimental evidence indicates the cell surface as the most likely site for the enzyme. The transferase synthesizes both glycolipids and glycoproteins. The lipid compounds have properties suggestive of lipid-linked mono- and oligosaccharides which can function as intermediates in glycoprotein synthesis. The formation of these compounds by a cell surface enzyme suggests that lipid-linked intermediates may play an important role in the glycosylation of membrane components.

Adenosine Monophosphate↗
PubMed1976

Ectogalactosyltransferase studies in fibroblasts and concanavalin A-stimulated lymphocytes.

In this communication, we have demonstrated that hydrolysis of the nucleotide sugar can cause errors in the detection of an ectoglycosyltransferase. Spleen cell suspensions can incorporate radioactivity when incubated with labeled UDP-galactose, but all the activity is due to decomposition of the nucleotide sugar and uptake of the free sugar. The fibroblast cell lines can incroporate carbohydrate directly from UDP-galactose. Several criteria are presented with can be used to demonstrate that a nucleotide sugar is the direct carbohydrate donor.

Galactose↗
PubMed1976

Carbohydrate compositions of normal, spontaneously transformed, and virally transformed cells derived from BALB/c mice.

Carbohydrate compositions of chloroform: methanol-soluble and -insoluble complex polysaccharides have been studied in cell lines derived from BALB/c mice. The cells used in these studies include normal cells, spontaneous and viral transformants that cause tumors that regress, and spontaneous and viral transformants that cause progressively growing tumors that kill immunocompetent BALB/c mice. The carbohydrates were determined by gas-liquid chromatography. Some of the transformed cell lines compared with normal cells have altered carbohydrate compositions, including decreased sialic acid levels and decreased N-acetylgalactosamine in chloroform: methanol-soluble material. Significant decreases in total carbohydrates of chloroform: methanol-soluble material were also observed in some of the transformed cells. However, these changes alone do not predict cancer. Transformed cell lines that cause progressively growing tumors tend to have fewer alterations in carbohydrates of complex polysaccharides than lines causing tumors that regress.

Animals↗
PubMed1975

A comparison of glycosyltransferase activities and malignant properties in normal and transformed cells derived from BALB/c mice.

The ability of suspensions of BALB/c cells to catalyze the incorporation of nucleotide sugars into complex polysaccharides has been compared. These cells have previously been characterized for concanavalin A-induced agglutinability, tumorigenicity, and malignancy. All of the cell lines tested catalyze transfer of the sugar moieties of cytosine 5-monophosphate N-acetylneuraminic acid, uridine 5-diphosphate galactose, uridine 5-diphosphate N-acetylgalactosamine, uridine 5-diphosphate N-acetylglucosamine, uridine 5-diphosphate glucose, and guanidine 5-diphosphate monnose into glycoproteins and glycolipids. While some transformed lines exhibit alterations in transferase levels, others cannot be distinguished from normal cells. Normal cells, transformed cells that cause tumors that regress, and transformed cells that cause tumors that kill an immunologically competent host show growth-dependent changes in transferase activities. Determining the ability to catalyze carbohydrate transfer is insufficient for predicting the tumorigenic and malignant properties of a cell line.

Agglutination↗
PubMed1973

Dibutyryl cyclic adenosine 3'5' monophosphate, sugar transport, and regulatory control of cell division in normal and transformed cells.

Swiss 3T3 cells exhibit contact-regulated cell growth and have a lower ability to transport 2-deoxyglucose than polyoma (Py)-transformed 3T3 cells. Py3T3 cells treated with dibutyryl cyclic adenosine 3'5' monophosphate (dBcAMP) and theophylline have reduced cell growth and transport 2-deoxyglucose at the same rate as normal 3T3 cells. Evidence that the cessation of cell growth and reduced transport abilities in Py3T3 cells does not represent a return to contact-regulated growth comes from the following observations. First, treating high density Py3T3 cells with dBcAMP allows more than two doublings of cell number, even though ability to transport 2-deoxyglucose is returned to levels equal to those of normal 3T3 cells. Second, dBcAMP prevents serum-stimulated increases in 2-deoxyglucose transport in Py3T3 but not in 3T3 cells.

Agglutination↗
PubMed1971

Contact-inhibited revertant cell lines isolated from SV40-transformed cells. I. Biologic, virologic, and chemical properties.

Two contact-inhibited "revertant" cell lines were isolated from an SV40-transformed mouse 3T3 cell line (SV-3T3) after exposure to 5-fluoro-2'-deoxyuridine. Revertant cells resembled 3T3 cells morphologically and grew to saturation densities which were similar to those of 3T3 cells; however, revertant cells readily formed both single and multinucleated giant cells in confluent cultures. SV40 virus was rescued from revertant cells by fusion with permissive monkey cells. The rescued virus transformed 3T3 cells with the same efficiency as wild type virus, and produced transformed colonies which were phenotypically similar to those produced by wild type virus. The revertant cells also resembled normal 3T3 cells in that they contained higher quantities of sialic acid than SV-3T3 cells. An inverse correlation was found between the saturation density of cells and their sialic acid content. Collagen content, however, of revertant cells was similar to that of SV-3T3 cells. The data presented suggest that the property of contact inhibition in revertant cells is related to the sialic acid content of the plasma membrane and that changes in sialic acid content of transformed cells are not directly specified by the viral genome.

Animals↗
PubMed1971

Modification of Sindbis virus glycoprotein by host-specified glycosyl transferases.

The amino acid sequence of the membrane glycoprotein of Sindbis virus is specified by the viral genome, but it has not been determined whether the carbohydrate portion of this molecule is specified by the cell or by the virus. We have examined two of the enzyme activities which catalyze transfer of monosaccharides to glycoprotein (sialyl and fucosyl transferases). Comparison of particulate enzyme preparations from infected and uninfected cells showed no difference in either the specific activity or acceptor specificity of these enzymes. This is impressive in view of the fact that the Sindbis membrane glycoprotein is the only glycoprotein synthesized in the infected cell. It was also determined that sialyl transferase from uninfected cells is capable of transferring ((3)H) sialic acid to acceptor prepared from Sindbis membrane glycoprotein. These results imply that at least some of the carbohydrate of the virus glycoprotein can arise by host modification.

Acrylates↗