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M L Beck

Publications and source records attributed to M L Beck.

15 recordsLinked to original sources
PubMed1977

BS II lectin: a second hemagglutinin isolated from Bandeiraea simplicifolia seeds with affinity for type III polyagglutinable red cells.

BS II lectin, a second hemagglutinin isolated from Bandeiraea simplicifolia seeds, agglutinated the red cells from 11 patients manifesting the 'acquired B' antigen phenomenon. The results of serological studies indicate that this lectin has specificity for the type III polyagglutinable receptors rather than for the 'B-like' antigens present on 'acquired B' red cells. Two other blood samples which did not possess 'acquired B' antigens were also found to react with BS II lectin. Both of these samples were shown to have properties similar to those reported for Tk red cells. The serological characteristics of red cells modified in vitro by a culture broth of Bacteroides fragilis suggest that type III polyagglutinable receptors are identical to those associated with Tk red cells.

ABO Blood-Group System↗
PubMed1977

RH nomenclature.

Explore the source record for details and available documents.

Rh-Hr Blood-Group System↗
PubMed1975

A serum haemagglutinating property dependent upon polycarboxyl groups.

A serum agglutinin reactive with red cells in the presence of polycarboxyl groups is reported. It is likely that this represents an additional example of the type of agglutinin previously described as agglutinating red cells in the absence of ionized calcium. Experimental evidence is presented indicating that it is free polycarboxyl groups that potentiate agglutination and that any metal ion, such as calcium, capable of chelating with these groups will prove to be inhibitory.

ABO Blood-Group System↗
PubMedDate not supplied

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↗
PubMedDate not supplied

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↗
PubMedDate not supplied

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↗
PubMedDate not supplied

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↗
PubMedDate not supplied

The immunoglobulin structure of human anti-M agglutinins.

Fifty examples of human anti-M agglutinins were subjected to reductive cleavage using both 2-mercaptoethanol (2-ME) and dithiothreitol (DTT). Thirty-nine (78%) were resistant to inactivation by sulphydryl compounds indicating IgG composition. This was confirmed by column chromatography. The remaining eleven sera were sensitive to reduction cleavage. There was no obvious association of immunoglobulin composition of the antibody with previous immune exposure to the M antigen. These results confirm observations in the literature that anti-M agglutinins are an exception to the generally expected correlation of saline agglutinating activity with IgM structure.

Agglutinins↗