A novel enzyme immunoassay for the determination of phosphatidylserine-specific phospholipase A(1) in human serum samples.
BACKGROUND
The bioactive lipid lysophosphatidylserine (LPS) is postulated to induce important biological responses and to be produced by phosphatidylserine-specific phospholipase A(1) (PS-PLA(1)). To evaluate the functional roles of LPS in vivo, a facile assay method for PS-PLA(1) has been awaited.


METHODS
Recombinant human PS-PLA(1) was produced using a baculovirus system, and anti-human PS-PLA(1) monoclonal antibodies were generated. Two clones were then selected for a 2-site immunoassay. The resulting PS-PLA(1) assay reagent was applied to a commercial automated immunoassay analyzer.


RESULTS
Satisfactory results were obtained for the within-run and between-run precision, interference, detection limit, and linearity of this PS-PLA(1) assay. The mean+/-SD of the serum PS-PLA(1) antigen concentration in the 191 healthy subjects was 33.8+/-16.6microg/l, and the central 95th percentile reference interval for the serum PS-PLA(1) antigen concentration was 13.8-74.1microg/l. The concentration was significantly (p<0.001) higher among men (13.8-80.6microg/l) than among women (12.1-68.8microg/l). We did not find a correlation between PS-PLA(1) and existing laboratory tests.


CONCLUSIONS
The present PS-PLA(1) assay method can be applied to clinical laboratory testing, and further studies are warranted to establish its clinical significance.
Nakamura
Kazuhiro
K
Department of Clinical Laboratory, The University of Tokyo Hospital, Tokyo, Japan.
Igarashi
Koji
K
Ohkawa
Ryunosuke
R
Saiki
Naoya
N
Nagasaki
Mika
M
Uno
Kansei
K
Hayashi
Naoto
N
Sawada
Tetsuji
T
Syukuya
Kenichi
K
Yokota
Hiromitsu
H
Arai
Hiroyuki
H
Ikeda
Hitoshi
H
Aoki
Junken
J
Yatomi
Yutaka
Y
D000818:Animals; D001774:Blood Chemical Analysis / Q000379:methods*; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods*; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology; D057230:Limit of Detection; D016014:Linear Models; D008297:Male; D051379:Mice; D054466:Phospholipases A1 / Q000097:blood* / Q000276:immunology
D007073:Immunoglobulin E; C512665:PLA1A protein, human; D054466:Phospholipases A1