THE ROLE OF LIPIDS IN THE DETECTION OF LUPUS ANTICOAGULANT BY THE DILUTE RUSSELL VIPER VENOM TEST - ARE PLATELETS OR REAGENTS CONTAINING HEXAGONAL H-II PHASES NECESSARY
Kj. Stevenson et Jm. Seddon, THE ROLE OF LIPIDS IN THE DETECTION OF LUPUS ANTICOAGULANT BY THE DILUTE RUSSELL VIPER VENOM TEST - ARE PLATELETS OR REAGENTS CONTAINING HEXAGONAL H-II PHASES NECESSARY, British Journal of Haematology, 86(3), 1994, pp. 583-589
Liposomes prepared from rabbit brain extracts (RBE) and individual pur
e lipids (high phosphatidyl serine content, HIPS) were compared with f
rozen-thawed platelets (PLTS) in the dilute Russell Viper venom time (
dRVVt). While all three preparations demonstrated sensitivity to lupus
anticoagulant (LA) the highest detection rate was seen with RBE. For
confirmation of LA, high concentration RBE achieved the most efficient
correction of the defect. Electron microscopy and particle sizing sho
wed RBE to be small, discrete liposomes, whereas HIPS and PLTS were ag
gregates of larger diameter particles. Low-angle X-ray diffraction sho
wed no evidence of hexagonal H-II phase. There appears to be no specif
ic requirement either for platelets or for reagents containing hexagon
al H-II phases in the dRVVt. The dRVVt can be optimized by incorporati
ng a simple dilute rabbit brain lipid mixture for detection of LA and
a concentrated mixture as a correcting reagent.