Automatic Marsh method for detection and identification of erythrocyte antibodies in patients and blood donors.

Using a Technicon autoanalyzer method of Marsh 752 sera of patients, Rh-negative subjects in the initial stage of immunization with Rh-positive blood, and healthy blood donors were investigated. In 56 sera (8.7%) positive reactions with standard erythrocytes were found. In 21 of these cases (36%) specificity of antibodies was established. They were mostly alloantibodies or autoantibodies against Rh antigens. In 1 case anti-Ika alloantibody and in 1 case anti-K autoantibody were demonstrated. Antibodies with undetermined specificity belonged to the so called "analyzer antibodies", which are detected only by the automatic methods, and probably have no clinical importance. The possibility of recording by the autoanalyzer of subthreshold levels of alloantibodies undetected by other methods may be of great practical importance of patients receiving multiple transfusions of blood and for immunized blood donors.

[Detection of light chains of warm-type autoantibodies in autoimmune hemolytic anemia with the aid of an autoanalyzer]. / Wykrywanie lancuchów lekkich autoprzeciwcial typu cieplego w niedokrwistosciach autoimmunohemolitycznych przy uzyciu autoanalizatora.

A method was evolved for detection of light chains of erythrocyte autoantibodies using a Technicon II AutoAnalyser with properly selected dilutions of bromelin and methylcellulose and anti-kappa and anti-lambda sera. It was demonstrated that the method is superior to the direct Coombs test because it made possible detection of one or both light chains in warm autoantibodies coating the erythrocytes of 20 patients with autoimmunohaemolytic anaemias in whom they could not have been detected by the manual method. It was found that in warm-type autoantibodies light chains can be detected always and that in some cases only one light chain is found.

Automated screening of red cells for the detection of autoantibodies.

The AutoAnalyser Technicon II system was adapted for screening red cells for the presence of warm-type autoantibodies. A significant decrease in optical density was recorded when the red cells of 38 patients with autoimmune haemolytic anaemia were tested using the bromelin-methylcellulose method. This was never seen with the red cells of 226 patients with other diseases or of healthy blood donors. The method is very simple and more sensitive than the manual direct antiglobulin test.