Detection of anti-human T-lymphotropic virus type I antibody in whole blood by a novel counting immunoassay.
BACKGROUND
Assays to screen for and confirm the presence of the antibody for human T-lymphotropic virus type I (HTLV-I) are currently performed with serum or plasma. We developed and evaluated a new counting immunoassay (CIA) for the detection of HTLV-I antibody in whole blood, using recombinant and synthetic peptide antigens.


METHODS
We assessed the CIA for detection of HTLV-I antibody in whole blood and plasma. The CIA is an immunity-measuring method that combines latex agglutination with particle-counting technology. The numbers of agglutinated latex particles, single latex particles, and blood cells in a sample are measured based on differences in particle size between latex particles and blood cells.


RESULTS
The CIA and ELISA methods were in agreement for all 24 plasma samples tested, including those from 6 patients with HTLV-I-associated diseases, 6 HTLV-I carriers, and 12 HTLV-I antibody-negative individuals. The concordance between the ELISA (plasma) and the CIA (whole blood) for samples from 24 patients was 100%. The concordance between a particle agglutination method (plasma) and the CIA (plasma or whole blood) for 1065 patients was 99.5%. The concordance between results obtained for 1065 pairs of plasma and whole blood samples with the CIA method was 100%. HTLV-I antibody in whole blood was stable for 3 days after blood collection. With this CIA method, results were available within 15 min.


CONCLUSIONS
The CIA method can be used in screening for HTLV-I. The use of whole blood rather than serum or plasma reduces the sample volume and number of blood collections required, as well as assay time.
Yamaguchi
Kazunari
K
Blood Transfusion Service, Kumamoto University School of Medicine, 1-1-1 Honjo, Kumamoto 860-8556, Japan. kyama@gpo.kumamoto-u.ac.jp
Yonemura
Yuji
Y
Okabe
Hiroaki
H
Takahama
Yoichi
Y
Nagai
Shinya
S
Yamaguchi
Haruki
H
Hirai
Kojiro
K
D000914:Antibodies, Viral / Q000097:blood*; D001322:Autoanalysis; D015368:Human T-lymphotropic virus 1 / Q000276:immunology*; D006801:Humans; D007118:Immunoassay
D000914:Antibodies, Viral