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Biomedical subjects

J E Butler

Publications and source records attributed to J E Butler.

At least 181 records · Page 10Linked to original sources
PubMed1978

Evaluation of enzyme-linked immunosorbent assay for quantitation by subclass for bovine antibodies.

The enzyme-linked immunosorbent assay (ELISA) was evaluated for use in the quantitative measurement of bovine immunoglobulin IgG1 and IgG2 antibodies. A method for standardization was devised in which IgG1 or IgG2 was directly adsorbed to polystyrene tubes and the actual degree of binding was calculated by using different input amounts of 125I-labeled IgG1 or IgG2. Values for quantity of IgG1 antibodies to human serum albumin were only slightly higher when measured by the ELISA than when measured by quantitative precipitation although the value measured by the ELISA for IgG2 antibodies was twice that determined by quantitative precipitation. This discrepancy could result from conjugate cross reactivity, differences in affinity between antibodies of the 2 subclasses, or the occurrence of IgG2 nonprecipitating antibodies. The danger of overlooking subclass anti-globulin cross reactivity because of the failure to detect it by immunoprecipitation, also is illustrated. In addition, only enzyme-antibody conjugates prepared with specifically purified antibodies were effective, and reproducibility of individual data points required that 4 replicate determinations be performed. Advantages, pitfalls, and limitations of the ELISA are discussed.

Animals↗
PubMed1976

Tickborne oculoglandular tularemia: case report and review of seasonal and vectorial associations in 106 cases.

A patient acquired tickborne oculoglandular tularemia in early summer in rural Virginia. Tick exposure may be a clue to the diagnosis of tularemia in the eastern as well as the western United States, especially in summer months. A review of the experience with tularemia in Virginia for the last 13 years shows a bimodal seasonal incidence of tularemia with an associated vector exposure in 77.4% of 106 cases. The majority of cases occurring during winter months have been associated with rabbit exposure, while those in summer months are often associated with tick exposure.

Aged↗
PubMed1976

Two immunochemically and physicochemically distinct secretory components from rat exocrine secretion.

Two proteins were isolated from rat milk by using ion-exchange and gel filtration chromatography and shown to be secretory components by the criteria of: a) occurrence as free proteins in exocrine secretions, as well as bound to exocrine IgA while absent from serum and serum IgA, b) immunohistochemical localization in the epithelial cells of the gut, c) dissociability from and in vitro binding to 11 S SIgA, d) cross-reactivity with antisera to mouse and bovine secretory components, and e) significant peptide homology with bovine secretory component. The secretory components were immunochemically and physicochemically distinct as shown by: a) the lack of cross-reactivity between their specific antisera and differential reactivity with anti-bovine FSC and anti-mouse SC, b) different electrophoretic mobilities, c) DEAE elution profiles, d) carbohydrate contents, e) molecular weights, and f) apparent polypeptide chain constitution. Another interesting difference in the two is that only one of the components dissociates spontaneously from SIgA. Possible functions of two secretory components are discussed.

Animals↗
PubMed1972

Quantitative changes associated with calving in the levels of bovine immunoglobulins in selected body fluids. I. Changes in the levels of IgA, IgGl and total protein.

Levels of bovine IgA, IgG1 and total protein (TP) were determined in serum, saliva, tears and individual quarter lacteal secretions of six Holstein-Friesian cows sampled from six weeks before to four weeks after parturition. Hierarchal analyses of variance indicated significant variations among weeks, cows and quarters of the udder. A precipitous but non proportional drop in the levels of IgA and IgA1 in lacteal secretions occurred at calving. There was a concomitant increase in IgG1, and decrease in IgA, in serum. Correlation studies supported the concept of selective transport of IgG1 from serum to lacteal secretions in regulated amounts independent of serum IgG1 levels. Changes in the IgG1/TP ratio of serum and lacteal secretions supported the idea of a decrease in the selective transport mechanism. Correlation studies and estimations of secretory IgA (SIgA) in serum suggest that serum IgA is derived from IgA synthesized in secretory tissues. Highly significant correlations between IgA and IgG1 levels in all secretions postpartum suggest that local IgA synthesis and either IgG1 transport or local IgG1 synthesis are initiated by the same stimuli. Although some of the variation in the level reported for IgA and IgG1 in secretions resulted from protein dilution, much of the variation represents physiological differences between individual animals and tissues in the same animal. An IgG2/IgG1 ratio approaching that of serum occurred in a mastitic quarter of one cow. IgA was the principal immunoglobulin in saliva and tears, comprised a greater proportion of the immunoglobulin in milk whey than in prepartum lacteal secretions and was a minor immunoglobulin in bovine serum.

Animals↗
PubMed1971

Physicochemical and immunochemical studies on bovine IgA and glycoprotein-a.

1. Bovine secretory IgA (SIgA) from colostrum (mol. wt. about 410,000) is composed of four alpha-chains (mol. wt. 61,000), four light chains (mol. wt. 23,000) and one molecule of glycoprotein-a (mol. wt. 70,000-86,000). The alpha-chains are antigenically and physicochemically distinct from the heavy chains of IgM, IgG1 and IgG2 while the light chains are identical to those occurring on other bovine immunoglobulins. Glycoprotein-a and bovine free secretory component are identical and the former name should be abolished. Much of this protein is covalently bonded to IgA. 2. The gel filtration behavior of serum IgA suggests it is a dimer. 3. The elution behavior of IgA and SIgA from ion-exchange columns and the solubility characteristic of SIgA in the presence of Zn2+ are similar to those of human and rabbit IgA. 4. The disc electrophoretic behavior of IgA and SIgA are distinct from IgM, dimeric IgG1, 7-S IgG and glycoprotein-a. Dimeric IgG1 (s20,w = 9.5) is abundant in colostrum and is similar in size to SIgA. 5. Bovine IgA shows physicochemical and immunochemical heterogeneity when studied by gel filtration, disc electrophoresis, immunoelectrophoresis and ultracentrifugational analyses. Lacrimal and nasal SIgA possess antigenic determinants absent on colostral SIgA.

Animals↗