Molecular forms of galectin-1 from human placenta and trophoblast cells

Abstract

Galectin-1 (gal-1) is the best studied member of the galectin family of the human placenta assumed to play important roles in pregnancy. Standard isolation of gal-1 from human placenta using lactose extraction and affinity chromatography in the presence of a reducing agent, produced several known forms of gal-1, which were compared to the recombinant human gal-1 (rhgal-1) and oxidized recombinant human gal-1 (Ox-gal-1). Isolated placental gal-1 retained lectin binding activity, evidenced by hemagglutination and dot blot lectin assays. Characterization of the forms present by surface-enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF MS), based on hydrophilic interactions or immunorecognition, provided a sensitive tool for detection of the fine differences among the diverse molecular forms. The forms detected included previously established biologically active oxidized gal-1 and reduced gal-1, as well as some other currently uncharacterized (less investigate forms.