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A H Whiting

Publications and source records attributed to A H Whiting.

8 recordsLinked to original sources
PubMed1994

Development of an enzyme-linked immunosorbent assay for the detection of IgG subclasses in the serum of normal and diseased dogs.

The present study describes the development of an enzyme-linked immunosorbent assay capable of quantifying serum antibody of all four canine IgG subclasses. A panel of subclass-restricted and subclass-specific monoclonal antibodies was used to measure IgG subclasses in the serum of healthy dogs, as well as in dogs with a range of clinical diseases. The subclasses have been redefined as IgG1, IgG2, IgG3 and IgG4 based on a comparison with the relative concentration and electrophoretic mobilities of human IgG subclasses. In serum samples from healthy dogs, the concentration of IgG1 (mean, 8.17 +/- 0.95 mg ml-1) and IgG2 (mean, 8.15 +/- 3.16 mg ml-1) were very similar and considerably higher than the levels of IgG3 (mean, 0.36 +/- 0.43 mg ml-1) and IgG4 (mean, 0.95 +/- 0.45 mg ml-1). There was no apparent difference in the level of subclasses between the different breeds comprising this normal population. Sera from dogs with a range of immune-mediated or inflammatory diseases all had markedly elevated levels of IgG2 (more than 13 mg ml-1), but IgG1 decreased (less than 4 mg ml-1) to levels below the normal range.

Anemia, Hemolytic, Autoimmune↗
PubMed1994

Preparation of monoclonal antibodies specific for the subclasses of canine IgG.

Canine IgG is composed of four subclasses, which are defined as IgG1, IgG2, IgG3 and IgG4 on the basis of data from fast protein liquid chromatography, and their electrophoretic mobilities and relative concentrations in serum. This paper describes the preparation of mAbs specific for determinants on canine IgG2, IgG3 and IgG4. The mAb specific for IgG2 resulted from a conventional immunisation protocol. The mAb specific for IgG3 was a result of immunisation with IgG3 combined with the suppression of the immune response to IgG1 by passively administered anti-IgG1 antibody. The mAb specific for IgG4 resulted from immunisation with Fab or Fc fragments which were obtained by the cleavage of the IgG4 molecule with papain. The specificity of each mAb was established by using an enzyme-linked immunosorbent assay which showed that all three specific clones recognised a determinant in the Fd region of the canine immunoglobulin molecule.

Animals↗
PubMed1993

The separation and identification by monoclonal antibodies of dog IgG fractions.

Four fractions of IgG from normal dog serum have been successfully isolated by gel filtration followed by protein A and protein G affinity chromatography using the fast protein liquid chromatography (FPLC) system. Protein A chromatography produced three peaks: peak 1 was fallthrough material consisting of components which did not bind to protein A, peak 2 consisted of bound material eluting at pH 6, and peak 3 contained bound material eluting at pH 3.5. The three peaks were then subjected individually to protein G affinity chromatography. Peak 1 from protein A chromatography produced a fallthrough peak followed by a weakly binding component which eluted at pH 8, and was called peak w. Peak 2 from protein A chromatography bound to protein G and eluted as a single peak at pH 3.8, and was called peak x. Peak 3 from protein A chromatography emerged as two separate peaks (y and z) off the protein G column; peak y bound and eluted at pH 4.1, and peak z bound weakly to protein G and emerged as a broad band at pH 8. Peaks w, x, y and z have been named gamma w, gamma x, gamma y and gamma z, respectively, and there purified IgG fractions were used to immunize mice for the preparation of monoclonal antibodies (McAbs). To date, two sets of McAbs have been produced: one which recognizes an epitope present in both gamma w and gamma z fractions and another set of McAbs which recognizes an epitope in the gamma x and gamma y fractions.

Animals↗
PubMed1982

Immunological studies with human aortic elastin.

Antibodies to human fetal aortic elastin were isolated from sheep immunized with alpha-elastin peptides. In preliminary tests of specificity using passive hemagglutination, partial cross-reactivity was demonstrated with alpha-elastin from other species. However, in a double antibody radio-immunoassay alpha-elastin peptides from other mammalian species failed to compete with 125I-labelled human alpha elastin. These results suggest the existence of at least two different antigenic sites on the elastin molecule. One, a high affinity site, demonstrates species specificity at low antigen/antibody concentrations. The other, a low affinity site, is common to mammalian elastins and is demonstrated at high antibody/antigen concentrations. In the radioimmunoassay the antibodies showed considerably less avidity for adult human alpha-elastin than for the fetal antigen. This implies that the species specific site is age-dependent and probably involves the cross-linking region of the elastin molecule. Using the sheep antiserum immunohistochemical staining of elastic tissue has been developed. This should prove to be a useful technique for studying polymeric elastin in intact tissue by light microscopy and at the ultrastructural level.

Adult↗
PubMed1979

Molecular weights and Stokes radii of soluble elastins.

Soluble elastin was isolated from lathyritic chick aorta using neutral salt solutions in the presence of beta-amino propionitrile. The effect of a carboxy-methylation step in conjunction with proteolytic inhibitors was investigated. Hydrodynamic (Stokes) radii of soluble elastins were measured by gel filtration and the molecular size and weight distribution in purified fractions are reported.

Amino Acids↗
PubMed1977

The coacervate-sol transition observed with alpha-elastin and its N-formyl O-methyl derivative.

The coacervate phase produced by raising the temperature of solutions of blocked alpha-elastin has water content and fibrillar structure at electron microscope level similar to fibrous elastin (Cox, B.A., Starcher, B.C., Urry, D.W. (1973) Biochim, Biophys. Acta 317, 209-213). The stability ranges of the coacervates under varying conditions of temperature, pH, salt concentration and concentration of added organic solvent have been investigated with results that suggest a marked sensitivity of elastin conformation to solution conditions.

Elastin↗