Non-competitive enzyme-linked immunosorbent assay for human apolipoprotein SAA or S.

Purified antibodies against human apolipoprotein S were used to measure apo S levels in human plasma by a sandwich ELISA technique. The method developed was highly sensitive and specific. A reliable calibration of a plasma standard was obtained by reassociating the purified protein with plasma HDL. A significant correlation (r = 0.69) was found between plasma apo S and CRP values. This correlation coefficient reached 0.97 when the plasma samples were selected according to additional clinical and laboratory criteria.