[Basic and clinical evaluation of an immunoradiometric competitive inhibition assay for 2----6 sialyl Lewis a antigen--1. Evaluation of assay conditions and normal values].
We describe an immunoradiometric competitive inhibition assay of the serum levels of the 2----6 sialyl Lewisa antigen, using "SLA 2-6 Otsuka" kits. The assay required only duplicate 50-microliters samples, and the concentration of 2----6 sialyl Lewisa antigen in serum was determined by reference to a standard curve ranging from 0 to 160 arbitrary U/ml. The intra- and inter-assays reproducibilities were good and analytical recovery of antigen were excellent. The serum levels of the antigen were highly dependent on the Lewis blood types of the tested individuals; i.e., the levels of the antigen in the sera of the Lewisa-b- individuals were significantly lower than those of the antigen obtained with the Lewisa+b- and Lewisa-b+ individuals. The cut-off value (42 U/ml) was obtained as mean + 2SD, which was carefully calculated from the antigen levels in sera of the non-Lewisa-b- individuals.
Imura
H
H
2nd Dept. of Internal Medicine, Faculty of Medicine, Kyoto University.
Takahashi
T
T
Matsuda
T
T
Yoshida
O
O
Ohkura
H
H
Seitetsu
Y
Y
Seino
Y
Y
Ishii
M
M
Kuwabara
M
M
Ariyoshi
Y
Y
D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal; D001667:Binding, Competitive; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D007564:Japan; D007983:Lewis Blood Group Antigens / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D011863:Radioimmunoassay / Q000379:methods; D011933:Reagent Kits, Diagnostic; D012015:Reference Standards; D012016:Reference Values; D015203:Reproducibility of Results
D000911:Antibodies, Monoclonal; D007983:Lewis Blood Group Antigens; D011933:Reagent Kits, Diagnostic