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S R Pierce

Publications and source records attributed to S R Pierce.

6 recordsLinked to original sources

Unexpected limitations in the use of commercial antiglobulin reagents.

The majority of antiglobulin sera used in blood banks in the USA are commercially prepared immune rabbit sera, designed to be reactive only with human red blood cells sensitized with immunoglobulins or complement components. Current manufacturing methods result in a product that gives reliable specific reactions provided that the test red blood cells are normal, particularly with respect to sialic acid levels. This report describes our findings of false positive antiglobulin tests caused by incompletely absorbed antiglobulin reagents when cells with low sialic acid levels were tested. An evaluation of nine commercially prepared antiglobulin reagents revealed, in many of them, the presence of anti-species antibody, anti-T, and anti-Tn. Blood bank personnel must be aware of these characteristics especially when testing either enzyme premodified or polyagglutinable cells. The use of incompletely absorbed reagents might account for positive direct antiglobulin tests that are encountered occasionally in apparently normal healthy individuals. Furthermore, recent protocols advocating the use of trypsinized cells for the evaluation of anti-C3d activity of antiglobulin sera are invalid if the reagent is inadequately absorbed of anti-species agglutinins.

Agglutinins

Serologic activity of fatty acid dependent antibodies in albumin-free systems.

Fatty acid dependent agglutinin (FADA) refers to serum with the special ability to cause agglutination of red blood cells in the presence of certain fatty acids. The agglutinating mechanism is unclear. It has been proposed that the agglutinin reacts with albumin that has been conformationally altered by sodium caprylate and that the immune complex is passively adsorbed onto red blood cells. This report presents data that contradicts the proposal assigning a specific role to albumin in the agglutinating mechanism. FADA were isolated by column chromatography of resolubilized euglobulin preparations. No evidence of contamination with albumin was obtained in those IgM fractions possessing FADA activity. We propose, as an alternative explanation, that the serologic activity of FADA depends upon the interaction of IgM agglutinins with haptenic fatty acids.

Antibody Specificity

Coexistent Tk and VA polyagglutinability.

Serologic investigations of the red blood cells of two patients indicated polyagglutination as the cause of compatibility problems. Lectin studies to classify the variety of polyagglutination demonstrated the simultaneous exposure of two latent membrane receptors, Tk and VA. It is proposed that different bacterial enzymes were responsible.

Aged

Auto anti-Kpb associated with weakened antigenicity in the Kell blood group system: a second example.

An 84-year-old woman with intestinal bleeding had marked reduction of red blood cell antigenicity in the Kell system, and a positive direct antiglobulin test caused by auto-anti-Kpb. KX antigen activity of her cell was increased, an observation which supports the belief that KX marks a precursor structure utilized in the normal Kell biosynthetic pathway. It is postulated that reduced Kell antigenicity was an acquired change that resulted from enzymatic degradation, possibly of bacterial origin.

Adolescent