Abstract
A pregnancy-associated leporine protein-2 (PALP-2) was isolated from serum of pregnant rabbits by gel filtration, ion exchange and affinity chromatography. The purified PALP-2 migrated like β globulin and had a molecular size of approximately 45, 000. The isoelectric point of PALP-2, determined by isoelectirc focusing, was 5.5. This protein was species-specific; no reaction being seen with pregnancy-associated serum proteins in term maternal serum of human and rat. The immunoreactivity of PALP-2 was unaffected by heat treatment at 57°C for 30 minutes, variably changed on incubation at 65°C for 30 minutes, and stable at 4°C for a week or at -20°C for 24 weeks.
