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Biomedical subjects

G W Warr

Publications and source records attributed to G W Warr.

At least 73 records · Page 4Linked to original sources
PubMed1979

The immunoglobulin-like T-cell receptor. I. In situ demonstration of immunoglobulin Fab-region determinants of rodent T- and B-lymphocytes using chicken antibodies.

Antibodies were raised in chickens to the (Fab')2 fragment of normal murine IgG and to the k-myeloma protein MOPC 41. Following appropriate absorptions or purification by immune affinity chromatography the chicken antibodies bound specifically to both T- and B-cells of mice, rats and guinea-pigs as detected by quantitative cytofluorescence, radioactive binding assays and transmission and scanning immunoelectronmicroscopy. These antibodies are directed against polypeptide determinants of the Fab fragment, block antigen binding by purified idiotype-bearing murine antibodies, and provide useful probes for visualization and analysis of immunoglobulin-like surface receptors of rodent B- and T-cells.

Animals↗
PubMed1979

Binding of canine IgM and IgG to protein A of Staphylococcus aureus: a simple method for the isolation of canine immunoglobulins from serum and the lymphocyte surface.

The binding of normal canine serum IgG and IgM to staphylococcal protein A is described. Virtually all (greater than 99%) of IgG and up to 90% of IgM could be removed from canine serum, utilizing this phenomenon. The nature of the bound material was confirmed by immunodiffusion in agar, radioimmunoassay, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Attempts to elute differentially IgG and IgM from protein A-Sepharose columns, using gradients of pH or the chaotropic agent sodium thiocyanate, were unsuccessful. This phenomenon provides a basis for the isolation of canine IgM from serum. Lymphocyte surface IgM, studied by lactoperoxidase-catalyzed membrane radioiodination and solubilization in nonionic detergent, also showed the property of binding to staphylococcal protein A.

Animals↗
PubMed1979

Membrane immunoglobulin is present on thymic and splenic lymphocytes of the trout Salmo gairdneri.

Three rabbit antisera raised to trout IgM showed positive immunofluorescent reactions with lymphocytes of trout spleen and thymus. These antisera showed no detectable cross-reactivity with keyhole limpet hemocyanin, as determined by direct radioimmune precipitation and adsorption, and did not appear to react significantly with carbohydrate moieties on trout IgM, as determined by the failure of proteolytic digests of trout IgM to inhibit in radioimmunoassay against intact trout IgM. Membrane immunoglobulin determinants were detectable on the membrane of both thymocytes and splenocytes with the lactoperoxidase-catalyzed iodination reaction. Radioimmunoassay of lysates of lymphocytes confirmed the association of immunoglobulin with trout thymocytes. By radioimmunoassay, lysates of thymic and splenic lymphocytes contained similar amounts of immunoglobulin, equivalent to approximately 8 X 10(4) molecules of IgM per cell (calculated as the monomer micro 2L2).

Animals↗
PubMed1978

Visualization of a guinea pig T lymphocyte surface component cross-reactive with immunoglobulin.

Thymus-derived lymphocytes (T cells) show exquisite specificity in recognition of antigens, but the nature of the cell surface receptor is controversial. Although antigen recognition mediated by immunoglobulin variable (V) regions remains the minimal hypothesis, it has been extremely difficult to definitely establish the presence of immunoglobulins on these cells. Chicken antibodies, produced against the (Fab')2fragment of mouse immunoglobulin G (IgG) and purified by binding to and elution from IgG-Sepharose 4B, bind to an endogenously synthesized surface component of guinea pig T cells. The binding occurred via a cross-reaction with murine k chain and a heavy chain determinant localized in the Fd region, and was visualized by immunofluorescence and immunoelectronmicroscopy using both transmission and scanning techniques. These data provide direct evidence for the presence of a surface component related to immunoglobulin on T lymphocytes.

Animals↗
PubMed1978

Phylogenetic origins of immune recognition: naturally occurring DNP-binding molecules in chordate sera and hemolymph.

A method is described which allows the isolation of small quantities of DNP-binding antibodies of both high- and low-molecular-weight classes. The only detectable DNP-binding protein in the serum of placoderm-derived vertebrates was immunoglobulin in nature, and of the order of less than or equal to 1% total serum immunoglobulin. Proteins in the serum of the urochordate Pyura stolonifera, which bind to both DNP and erythrocyte antigens, showed charge heterogeneity and an apparent subunit molecular weight of approximately 65,000 to 70,000 daltons.

Animals↗
PubMed1978

Specific immune recognition by lymphocytes: an evolutionary perspective.

In this review, we analyze data pertinent to the origins of specific immune recognition by lymphocytes. The phenomena of immunity in invertebrates and the cells that might be involved in these processes are considered. We conclude that the existence of vertebrate-type immunocompetent lymphocytes in invertebrates is not yet proven. All vertebrates apparently possess immunologically competent lymphocytes, and the following conclusions may be drawn: (1) Specific antigen recognition by lymphocytes of all vertebrates appears to be mediated by membrane-bound immunoglobulins. These immunoglobulins are, in all probability, distinct from secreted, serum immunoglobulins (antibodies), although serum and surface immunoglobulins share combining sites for antigen which are formed of variable regions. (2) There is evidence for similar functional divisions among the immune systems of all vertebrates, as reflected in the results of anatomical, functional, and physicochemical investigations of lymphocytes from animals as diverse as fish and mammals.

Adaptation, Biological↗
PubMed1978

Null cells in the mouse possess membrane immunoglobulins.

Null cells lacking typical T and B cell surface markers were isolated from the spleens of congenitally athymic mice by using either nylon wool or Sepharose macrobeads conjugated with rabbit antibody to mouse IgM to remove B lymphocytes. Although these null cells were negative for surface immunoglobulin by the criterion of immunofluorescence by using rabbit antisera to mouse heavy or light immunoglobulin chains, surface immunoglobulins were readily demonstrable by two alternative and independent techniques. First, by using chicken antibody to the (Fab')2 fragment of mouse IgG, nearly all null cells were positive for immunofluorescence. Second, immunoglobulins could be detected in lysates of null cells radioiodinated by the lactoperoxidase-catalyzed reaction. Analysis of the surface immunoglobulins of null cells by radioimmunoassay and polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate suggested that they are 1) qualitatively similar to those of B cells and 2) present in amounts between 10 and 30% of those of B cells.

Animals↗