Analytical performance of a sandwich enzyme immunoassay for pre beta 1-HDL in stabilized plasma.
We have established an immunoassay for pre beta 1-HDL (the initial acceptor of cellular cholesterol) using a monoclonal antibody, MAb55201. Because pre beta 1-HDL is unstable during storage, fresh plasma must be used for pre beta 1-HDL measurements. In this study, we describe a method of stabilizing pre beta 1-HDL, and evaluate the analytical performance of the immunoassay for pre beta 1-HDL. Fresh plasma was stored under various conditions with or without a pretreatment consisting of a 21-fold dilution into 50% (v/v) sucrose. Pre beta 1-HDL concentration was measured by immunoassay. In nonpretreated samples, pre beta 1-HDL decreased significantly from the baseline after 6 h at room temperature. Although pre beta 1-HDL was more stable at 0 degrees C than at room temperature, it increased from 30.2 +/- 8.5 (SE) to 56.5 +/- 5.5 mg/l apolipoprotein A-I (apoA-I) (P < 0.001) in hyperlipidemics, and from 18.4 +/- 1.2 to 37.9 +/- 3.3 mg/l apoA-I (P < 0.001) in normolipidemics after 5-day storage. After 30-day storage at -80 degrees C, pre beta 1-HDL increased from 29.0 +/- 4.0 to 38.0 +/- 5.7 mg/l apoA-I (P < 0.001) in hyperlipidemics, whereas it did not change in normolipidemics. In pretreated samples, pre beta 1-HDL concentration did not change significantly under any of the above conditions. Moreover, pre beta 1-HDL concentrations determined by immunoassay correlated with those determined by native two-dimensional gel electrophoresis (n = 24, r = 0.833, P < 0.05). An immunoassay using MAb55201 with pretreated plasma is useful for clinical measurement of pre beta 1-HDL.
Miida
Takashi
T
Division of Clinical Preventive Medicine, Department of Community Preventive Medicine, Niigata University Graduate School of Medical and Dental Sciences, Asahimachi 1-757, Niigata, Niigata 951-8510, Japan. miida@med.niigata-u.ac.jp
Miyazaki
Osamu
O
Nakamura
Yasushi
Y
Hirayama
Satoshi
S
Hanyu
Osamu
O
Fukamachi
Isamu
I
Okada
Masahiko
M
D015180:Electrophoresis, Gel, Two-Dimensional; D005615:Freezing; D053442:High-Density Lipoproteins, Pre-beta; D006949:Hyperlipidemias / Q000097:blood; D007124:Immunoenzyme Techniques / Q000379:methods*; D008075:Lipoproteins, HDL / Q000097:blood* / Q000276:immunology*; D013696:Temperature; D013997:Time Factors
D053442:High-Density Lipoproteins, Pre-beta; D008075:Lipoproteins, HDL