Human PAI2 (Plasminogen Activator Inhibitor 2 ) ELISA Kit (HUES03014)

PAI2 (SERPINB2) belongs to clade B of the serine protease inhibitor superfamily, the ovalbumin-related ov-serpins. The gene maps to chromosomal position 18q21.3 within the serpin cluster, sitting approximately 600 kb from BCL2. The protein exists as two isoforms: an intracellular non-glycosylated ~47 kDa form concentrated in monocytes, macrophages, keratinocytes, and trophoblasts, and a secreted glycosylated ~60 kDa form found in pregnancy plasma and inflammatory exudates. Both isoforms form SDS-stable covalent complexes with urokinase and two-chain tissue-type plasminogen activator.

For sample preparation, peripheral blood should be drawn into EDTA or citrate tubes and centrifuged within 30 minutes; aliquoted plasma stored at -80 degrees C limits proteolytic loss of SERPINB2. Cell culture supernatants from trophoblast or tumor lines can be concentrated through centrifugal ultrafiltration (e.g. 10 kDa cutoff) when expected expression falls near the assay's lower detection limit. The kit's biotin-streptavidin-HRP detection chain amplifies signal roughly 100-fold versus direct conjugation, supporting reproducible quantification across the standard curve.

Beyond classical fibrinolysis regulation, SERPINB2 has become a marker of tumor progression in cervical, breast, and colorectal carcinomas, a candidate indicator in pre-eclampsia and recurrent pregnancy loss, and an upstream modulator of macrophage survival through proteasome beta1 subunit interaction. The Assay Genie protocol therefore fits naturally into workflows that combine ELISA quantification with downstream western blot or immunohistochemistry validation of matched tissue, allowing protein-level confirmation of SERPINB2 transcriptomic hits. PAI2 shares 76% amino acid identity with mouse and 73% with rat, so cross-reactivity with rodent samples is expected to be limited.