Dorsam G, Harris L, Payne M, Fry M, Franson R
Department of Biochemistry and Molecular Biophysics, Virginia Commonwealth University, Richmond 23298-0614, USA.
Clin Chem. 1995 Jun;41(6 Pt 1):862-6.
Previously we reported that uremic plasma contained eight times more phospholipase A2 (PLA2) activity than control plasma (Costello et al., Clin Chem 1990;36:198-200). That study, however, did not distinguish between various PLA2s that could contribute to the observed increase. Therefore, we developed a sandwich ELISA to specifically quantify serum type II PLA2. By ELISA, uremic sera contained significantly more type II PLA2 than control sera (median = 1025 micrograms/L, range = 52-3320 micrograms/L vs median = 9.2 micrograms/L, range = 4.6-17.5 micrograms/L; P = 0.002). When serum samples were incubated with 1-[14C]oleate-labeled autoclaved Escherichia coli, activity was increased 14.6-fold in uremic vs normal serum, with a median of 6.5 mumol/min per liter (range 1.1-16.3) vs a control median of 0.49 mumol/min per liter (range 0.32-0.60; P = 0.002). Thus, ELISA detects about eightfold more immunoreactive type II PLA2 in uremic serum than does enzymatic analysis. Evidently, the increase in PLA2 activity previously observed in uremic plasma is primarily due to increased concentrations of type II PLA2.
我们之前报道过，尿毒症患者血浆中磷脂酶A2（PLA2）的活性是对照血浆的8倍（科斯特洛等人，《临床化学》1990年；36:198 - 200）。然而，该研究并未区分可能导致观察到的活性增加的各种PLA2。因此，我们开发了一种夹心酶联免疫吸附测定法（ELISA）来特异性定量血清II型PLA2。通过ELISA检测，尿毒症患者血清中的II型PLA2显著多于对照血清（中位数 = 1025微克/升，范围 = 52 - 3320微克/升，而对照血清中位数 = 9.2微克/升，范围 = 4.6 - 17.5微克/升；P = 0.002）。当血清样本与1 - [14C]油酸标记的高压灭菌大肠杆菌一起孵育时，尿毒症血清中的活性比正常血清增加了14.6倍，中位数为每升6.5微摩尔/分钟（范围1.1 - 16.3），而对照血清中位数为每升0.49微摩尔/分钟（范围0.32 - 0.60；P = 0.002）。因此，ELISA检测到的尿毒症血清中免疫反应性II型PLA2比酶分析多约8倍。显然，之前在尿毒症血浆中观察到的PLA2活性增加主要是由于II型PLA2浓度升高所致。
