Automated Red Cell Antibody Analysis. A Parallel Study

Abstract

The AutoAnalyzer method of red blood cell antibody detection can be adapted to identify the serological specificity of these same antibodies. In the present study, 1,152 AA-positive sera obtained during AA screening were investigated. In 217 (19%) of these sera blood group antibodies were identified by manual techniques. Since the AA techniques are generally more sensitive than manual methods an attempt was made to identify antibodies by the AA methods in 823 sera which were negative manually. The low-ionic strength-Polybrene (LISP) method was found to be suitable for antibody identification because of its sensitivity in the detection of most red cell antibodies and the small technical deviations of OD from the base-line. The bromeline-methyl cellulose (BMC) technique is less sensitive and often more difficult to interpret in antibody identification. In some cases, however, this method was the only one that gave positive reactions. In 214 instances antibodies were identified by the AA techniques, about half of which were anti-D’s, the others being RBC antibodies of more or less rare varieties. The relative frequency of these rare antibodies was higher in the group of manual-negative sera, 47 versus 21%, normally found. Positive identification but no clear-cut blood type antibody was found in 155 cases (19%). Indications were obtained that some of the reactions were due to HL-A antibodies. Antibodies to HL-A7 and HL-A5 were found to react with red cells. In addition the AA techniques seemed to be more sensitive to detect RBC autoantibodies than standard manual methods. However, the usefulness of the AA techniques for routine antibody identification is diminished by the relative slowness of the machine.

Improved antibody detection by the use of range expansion and longer filter wavelength in a low ionic strength-protamine sulphate Auto-Analyzer system.

“…Experiments revealed that the LISPS system enhanced the reaction of MNS and Fya antibodies. Anti-K gave reactions equivalent to manual antiglobulin tests, but the system was slightly less sensitive than the BMC system in detecting weak anti-D, thus confirming the findings of Perrault and Hogman (1971).…”

“…Habibi et al (1973) and Perrault and Hogman (1971) overcame this problem by utilizing a selected panel of donors, but the provision of sufficient fully typed fresh cells for antibody screening is often difficult. Marsh et al (1968) and Moore (1969) found that glycerol frozen cells failed to form satisfactory rouleaux in the BMC system, although Kolberg and Nordhagen (1975) have reported satisfactory results with frozen cells in this system.…”

An example of anti-s causing mild haemolytic disease of the newborn

“…Marsh et al (1968) found that their BMC system reacted well with anti-S but anti-s was not tested. While Perrault and Hogman (1971) observed that the detection of anti-s on the AutoAnalyzer was less sensitive than the most appropriate manual technique. the anti-s described in this case was detected at a much higher titre on the AutoAnalyzer than by the indirect antiglobulin technique.…”

Bestimmung varianter Rh-Blutgruppenmerkmale durch kontinuierliche photometrische Durchflußanalyse

“…Graduell differierende D u -Antigene können auch dem Erfahrenen bei der Abgrenzung Iow grade D u /d, insbesondere aber bei der Differenzierung high grade D U /D erhebliche Schwierigkeiten bereiten (4,5). -Die kontinuierliche Durchflußanalyse ermöglicht durch die photometrische Agglutinationsmessung den objektivierbaren Nachweis abgeschwächt reagierender Blutgruppenvarianten (6)(7)(8). Wir berichten über eine technische Erweiterung des Technicon-Geräts Autogrouper 16 C, die die kontinuierliche Erfassung des D-Allels D u und weiterer Rh-Varianten der Loci C und E ermöglicht sowie über Beobachtungen bei der Analyse von abgeschwächten Varianten Rh-Faktoren der 3 Rh-Loci.…”