Use of IgM monoclonal reagents licensed for tube tests in column agglutination technology.
BACKGROUND
Red cell (RBC) phenotyping using column agglutination technology (CAT) is currently limited by the reagents formulated in the system. To overcome this limitation, it was investigated whether monoclonal IgM reagents licensed for use with tube tests produced valid results with CAT.


METHODS
Commercial CAT, does not contain antisera, was used to evaluate Procedures A (40 microL of reagent and 10 microL of 4% RBCs) and B (50 microL of reagent and 50 microL of 0.8% RBCs) with or without incubation at room temperature. In Study 1, reagents were tested to determine whether potentiators inhibit the passage of antigen-negative RBCs through the column. In Study 2, CAT sensitivity was measured by the use of potency titrations to define a procedure for each reagent that matched or exceeded that of the tube method. In Study 3, the specificity of each reagent was determined in parallel with the CAT and tube tests. Typing of 1644 samples was performed.


RESULTS
Study 1: Free passage was obtained with all reagents. Study 2: Immediate-spin methods using CAT produced the same results as the tube method. Study 3: With 8048 comparisons made, discrepant results were found in 32 transfused patients and in 6 cord blood samples, mainly with Lewis reagents. With comparison of CAT and the standard tube method, complete agreement was obtained with Kell reagents, 99.9-percent agreement with Kidd reagents, and 98.9-percent and 99.4-percent agreement with Lewis reagents.


CONCLUSIONS
Most examined reagents seem suitable for use with CAT.
Morelati
F
F
Centro Trasfusionale e di Immunologia dei Trapianti, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Ospedale Maggiore, Milan, Italy.
Burlini
A
A
Reis
K J
KJ
Drago
F
F
Revelli
N
N
Villa
M A
MA
Guffanti
A
A
Italiano
Z
Z
Parravicini
A
A
Rebulla
P
P
Sirchia
G
G
D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal / Q000276:immunology*; D001788:Blood Grouping and Crossmatching / Q000379:methods*; D005069:Evaluation Studies as Topic; D006386:Hemagglutination Tests / Q000379:methods*; D006801:Humans; D007075:Immunoglobulin M / Q000032:analysis; D007231:Infant, Newborn; D007626:Kell Blood-Group System / Q000235:genetics / Q000276:immunology; D007667:Kidd Blood-Group System / Q000235:genetics / Q000276:immunology; D007983:Lewis Blood Group Antigens / Q000235:genetics / Q000276:immunology; D010641:Phenotype; D015203:Reproducibility of Results; D017186:Titrimetry
D000911:Antibodies, Monoclonal; D007075:Immunoglobulin M; D007626:Kell Blood-Group System; D007667:Kidd Blood-Group System; D007983:Lewis Blood Group Antigens