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Biomedical subjects

G W Warr

Publications and source records attributed to G W Warr.

At least 55 records · Page 3Linked to original sources
PubMed1984

Molecular analysis of the lymphocyte membrane.

Methods for the molecular analysis of lymphocyte membranes are reviewed briefly, and wherever possible presented in a manner relevant to comparative studies. The specific areas reviewed include the bulk isolation of lymphocyte membranes, the use of radioisotopes to covalently label lymphocyte membrane molecules, the use of lectins to characterize membrane glycoconjugates, and our current understanding of lymphocyte membrane immunoglobulins.

Animals↗
PubMed1984

Beta 2 microglobulin-like polypeptide of the goldfish, Carassius auratus.

Antisera to human beta 2 microglobulin (beta 2M) detected a plasma membrane molecule on goldfish (Carassius auratus) cells in immunofluorescence. A goldfish molecule detected by radioimmunoassay (RIA) co-eluted with human beta 2M on gel filtration. By affinity chromatography on immobilized antibody to human beta 2M, a molecule was purified (from extracts of goldfish) that showed, on SDS-polyacrylamide gel electrophoresis, a mobility similar to that of human beta 2M (apparent Mr 12,800 +/- 500).

Animals↗
PubMed1983

Lymphocyte heterogeneity in the trout, Salmo gairdneri, defined with monoclonal antibodies to IgM.

A monoclonal antibody to trout serum IgM was tested by immunofluorescence analysis with lymphocytes from thymus, spleen and head kidney. By visual examination, the antibody reacted with only a subpopulation of lymphocytes. The mean values +/- SE for positive cells were 5.2 +/- 2.3% in the thymus, 30.3 +/- 7.9% in the spleen and 12.4 +/- 3.0% in the head kidney. Flow cytofluorometric analysis revealed evidence of heterogeneity by size among the membrane IgM-positive cells of the head kidney and spleen. Depletion of head kidney cells positive for surface IgM by an immune affinity adherence technique of panning, using monoclonal anti-IgM, significantly reduced the mitogenic response to lipopolysaccharide but not to concanavalin A. It is suggested that this information supports the existence of distinct subpopulations of fish lymphocytes that may be homologous in certain respects to mammalian T and B type cells.

Animals↗
PubMed1983

Serological characterization of humoral lectins from the freshwater prawn Macrobrachium rosenbergii.

We have detected and partially characterized multiple lectins present in the serum of the freshwater prawn Macrobrachium rosenbergii. Since agglutination of erythrocytes (RBC) is not abolished by treatment with Vibrio cholerae neuraminidase (VCN), Macrobrachium shows an agglutination pattern different from that of other sialic acid-specific lectins such as Limulus polyphemus lectin. However, after absorption with primate and bird VCN-treated RBC, Macrobrachium serum exhibits high titers with untreated and pronase-treated RBC and no agglutination of VCN-treated RBC, suggesting a typical sialic acid specific lectin agglutination profile. Hemagglutination-inhibition tests indicate that sialic acid containing compounds are the best inhibitors for Macrobrachium lectins. Subterminal sugars and type of linkage are probably important for the lectin binding since bovine submaxillary mucin (containing mainly terminal NANA-alpha-2 6-GalNAc-) is a better inhibitor than fetuin (containing mainly terminal NANA-alpha-2 leads to 3-Gal-) and colominic acid (-NANA-alpha-2 leads to 8-NANA-) is a weak inhibitor.

Animals↗
PubMed1983

Immunoglobulin of the toadfish, Spheroides glaber.

The major serum immunoglobulin of the toadfish, Spheroides glaber, was shown to be a tetrameric IgM-like molecule of probable structure (mu2L2)4. The tetrameric molecule could be dissociated, without reduction, into dimeric and monomeric forms. A low molecular weight immunoglobulin present at levels of about one twentieth of those of the high molecular weight IgM was detected in serum.

Amino Acids↗
PubMed1983

Thymocyte plasma membrane of the rainbow trout, Salmo gairdneri: associated immunoglobulin and heteroantigens.

Thymic lymphocytes of the rainbow trout, S. gairdneri were disrupted and a plasma membrane containing fraction isolated by differential and buoyant density centrifugation. Radioiodine introduced into the membrane by the lactoperoxidase catalyzed reaction and immunoglobulin (identified by radioimmunoassay with monoclonal antibody) both copurified in the plasma membrane fraction. Rabbit antibody raised to the plasma membrane fraction showed a strong reaction with trout lymphocytes in immunofluorescence, was mitogenic for trout lymphocytes, and recognized lymphocyte membrane heteroantigens of molecular weight greater than 70,000 in the thymus and 45,000-95,000 in the head kidney.

Animals↗
PubMed1983

Evidence for the existence of a diverse family of immunoglobulin-related recognition molecules.

All classes of molecule postulated to play a role in recognition or to have some structural homology to immunoglobulins were compared by the S delta Q index of differences in amino acid composition. The results suggest that there is a wide family of immunoglobulin-related molecules that includes vertebrate immunoglobulins, T cell receptors, MHC products, C-reactive proteins, and (some) invertebrate lectins.

Amino Acid Sequence↗
PubMed1983

Xenoantisera against a murine T cell tumor product cross-react with immunoglobulin Fab determinants.

Some murine monoclonal T lymphoma cells express a surface component that reacts with chicken antisera produced against the Fab fragment of normal mouse IgG. In the present study, we use a solid phase immunoadsorbent consisting of affinity-purified chicken anti-Fab coupled to Sepharose to isolate a product produced by the in vitro T cell line, WEHI-7.1. The affinity-purified T cell surface molecule (IgT) migrated on SDS-PAGE as a single band of approximately 65,000 daltons. The object of these studies was to produce xenoantisera against the purified T cell product cross-reactive with Ig determinants and to characterize the antisera. Rabbits immunized with this purified molecule produced antibodies that reacted with Fab fragments of polyclonal mouse IgG and with the myeloma proteins MOPC-104E and MOPC-41, as detected by enzyme-linked immunosorbent assay (ELISA). This binding was eliminated by adsorption of the antisera with normal polyclonal IgG; however, adsorption with fetuin did not significantly affect the reactivity of the antisera. Radioimmune precipitation assays revealed that the rabbit anti-IgT bound to normal murine spleen and thymus cells; this reactivity was abrogated by adsorption with insolubilized polyclonal IgG. Competition radioimmunoassays demonstrated that detergent extracts of the thymus and the spleen contained material that inhibited the precipitation of MOPC-41; nonlymphoid cells lacked such material. The rabbit anti-IgT serum blocked the binding of antigen by normal T cells; adsorption of the antiserum with polyclonal IgG-Sepharose abrogated this blocking capacity. A solid phase immunoadsorbent prepared from the IgG fraction of the rabbit anti-IgT isolated a single component from formic acid-solubilized mouse thymus. This molecule had an approximate mass of 65,000 to 70,000 daltons. The anti-IgT serum isolated surface IgM and IgD from lactoperoxidase-catalyzed radioiodinated B cells. The anti-IgT serum detected IgM and IgG in mouse serum with the use of immunoelectrophoresis. The anti-IgT immunoadsorbent isolated several components from normal mouse serum, that, when analyzed by SDS-PAGE under reducing conditions, revealed bands corresponding to mu-, gamma-, and light chains as well as components that migrated between mu- and gamma-chains, and another component with an approximate mass of 45,000 daltons. Our results with antibodies to a purified T cell product indicate that a surface component of normal T cells and certain monoclonal T cell tumor lines is serologically related to the Fab fragment of serum Ig and is implicated in the binding of antigen.

Animals↗
PubMed1982

Behavior of unreduced polymeric and monomdric immunoglobulins in sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

Investigation of the electrophoretic behavior, in SDS-polyacrylamide and SDS-polyacrylamide-agarose gels, of IgMs and low mol. wt. Igs from four classes of vertebrates, as well as fragments derived from them, was carried out. A clear but unexpected straight-line relationship was observed for all Igs (and fragments) tested when relative mobility was plotted against log mol. wt for the unreduced molecules. Aberrant behavior of the low mol. wt Ig of Bufo marinus was shown to be due to the complete dissociation of the molecule into free light chains and heavy-chain dimers, in the presence of SDS.

Animals↗
PubMed1982

Evidence for low-molecular weight antibodies in the serum of a urodele amphibian, Ambystoma mexicanum.

Adult axolotls (A. mexicanum) were hyperimmunized with the haptenic determinant, azobenzene-arsonate (ARS). Specific antibodies were isolated from their serum by immune-affinity chromatography on immobilized ARS columns. Analysis of the specific ARS-binding molecules by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) indicated that these animals were capable of producing both high molecular-weight (presumably IgM) and low molecular-weight antibodies to the ARS hapten. The low molecular-weight anti-ARS antibody produced by one inbred colony of axolotls did not show any restricted heterogeneity, as assessed by isoelectric focusing. Our results suggest that regulatory events, not the absence of genetic information, may be responsible for the apparent lack of Ig isotype diversity in this species.

Ambystoma↗
PubMed1982

Studies on the contribution of putative anti-carbohydrate antibodies to the specificity of immunofluorescence staining of murine T cells with chicken anti-mouse (Fab')2 reagents.

Despite a large body of immunochemical data indicating that chicken antibodies specifically recognize immunoglobulin-like structures on mammalian T and B cells, the possibility has been raised that the fluorescence staining of murine T cells with chicken antibodies directed against the (Fab')2 fragment of pooled mouse IgG might be due to carbohydrate moieties shared by heavily glycosylated proteins such as fetuin and mucin. Therefore, the presence of antibody activity against these glycoproteins in chicken antisera to mouse IgG (Fab')2 fragments and to MOPC-41 (murine kappa chains) was tested using a double antibody radioimmune assay. No detectable binding of fetuin or mucin was found in our chicken anti(Fab')2 reagent, whereas activity against (Fab')2 fragments was readily detected. In spite of the lack of anti-mucin or anti-fetuin activity, these glycoproteins were capable, along with fetal calf serum, whole mouse IgG, and mouse (Fab')2 fragments, of inhibiting the binding of anti-mouse (Fab')2 to T cells assayed by double immunofluorescence. However, the effective inhibition by fetuin only occurred when very large amounts of the glycoprotein were used, and titration experiments indicated that fetuin, is on a molar basis, at least 60-fold less efficient and inhibitor of the fluorescence reaction than (Fab')2 and nearly 3000-fold less efficient on a molar carbohydrate basis. We conclude that chicken anti-(Fab')2 and anti-mouse kappa chains stain T cells specifically via an immunoglobulin-like determinant and not by anti-carbohydrate activity.

Animals↗
PubMed1980

Surface component of primate thymus-derived lymphocytes related to a heavy chain variable region.

In a study designed to determine whether T cells of man and higher primates express a surface component related to the variable region of immunoglobulin heavy chain (VH), chickens were immunized with the purified VH fragment of a monoclonal Waldenström macroglobulin. The antibody preparation reacted with a mu chain determinant contained in the Fd fragment and with individual determinants characteristic of the orginal Waldenström protein. As estimated by immunofluorescence analysis, a subpopulation of normal human peripheral T cells (approximately 30%) bound the anti-VH antibody. B-Cell lymphoma lines grown in vitro, as well as some T-cell leukemia lines of the cotton-topped marmoset (Sagiunus oedipus), also bound the anti-VH antibody. The VH-bearing component of the T-cell line 70-N-2 was labeled biosynthetically by incorporation of [3H]leucine and was precipitated specifically by anti-VH antibody. This component was characterized by an apparent mass of 70,000 daltons as assessed by polyacrylamide gel electrophoresis under reducing conditions in buffers containing sodium dodecyl sulfate. These data provide direct support for the hypothesis that some T cells express and synthesize a component related to immunoglobulin heavy chains.

Animals↗
PubMed1979

Structural and antigenic studies of an idiotype-bearing murine antibody to the arsonate hapten.

Mice of strain A/J responded to repeated intraperitoneal injection of Limulus hemocyanin derivatized with arsanilic acid by producing large quantities (approximately 5 mg/mL of ascites fluid) of IgG antibodies specific for this hapten. The antibodies possessed a characteristic idiotypic determinant and exhibited restricted heterogeneity as demonstrated by isoelectric focusing and primary N-terminal amino acid sequence analysis of isolated light and heavy polypeptide chains. Both light- and heavy-chain sequences were comparable to those of myeloma proteins in lack of heterogeneity. The N terminus of the light chain exhibited V KI sequence and only one position in the first 30 residues showed more than one amino acid. No variability was observed in the first 10 N-terminal residues of the heavy chain. Rabbit antiserum to the idiotype blocked binding of hapten by the purified antibody. The presence of both light- and heavy-chain antigenic determinants was required for optimal formation of the idiotypic determinant.

Amino Acid Sequence↗