Comparison of a gel microcolumn assay with the conventional tube test for red blood cell alloantibody titration.
BACKGROUND
Titration is a semiquantitative method used to estimate red blood cell (RBC) alloantibody reactivity. The conventional tube test (CTT) technique is the traditional method for performing titration studies. The gel microcolumn assay (GMA) is also a sensitive method to detect RBC alloantibodies. The aim of this study was to compare a GMA with the CTT technique in the performance of Rh and K alloantibody titration.


METHODS
Patient serum samples that contained an RBC alloantibody with a singular specificity were identified by routine blood bank workflow. Parallel titration studies were performed on these samples by both the CTT method and a GMA (ID-Micro Typing System anti-IgG gel card, Micro Typing Systems, Inc., an Ortho-Clinical Diagnostics Company).


RESULTS
Forty-eight samples were included, including 11 anti-D, five anti-c, 13 anti-E, one anti-C, three anti-e, and 15 anti-K. Overall, the two methods generated identical results in 21 of 48 samples. For 42 samples (87.5%) the two methods generated results that were within one serial dilution, and for the remaining six samples, results were within two dilutions.


CONCLUSIONS
GMA systems may perform comparably to the CTT in titrating alloantibodies to Rh and Kell antigens.
Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90509, USA. rhfinck@gmail.com
Rachel
R
Finck
Carrie
C
Lui-Deguzman
Shih-Mao
SM
Teng
Rebecca
R
Davis
Shan
S
Yuan
D001788:Blood Grouping and Crossmatching / Q000295:instrumentation / Q000379:methods*; D004912:Erythrocytes / Q000276:immunology*; D006801:Humans; D007518:Isoantibodies / Q000097:blood*; D007626:Kell Blood-Group System / Q000276:immunology*; D012204:Rh-Hr Blood-Group System / Q000276:immunology*; D017186:Titrimetry
D007518:Isoantibodies; D007626:Kell Blood-Group System; D012204:Rh-Hr Blood-Group System