Abstract:Defatted seeds of wilt-disease resistant were extracted overnight with PBS at 4 ℃. After centrifugation. 90% saturated (NH4)2SO4 was added to the supernatant. The precipitates were dialysed against H2O, then lyophilized. The purified lectin was obtained by DEAE-cellulose ion-exchange chromatography, Sephadex G-100 filtration, and Sepharose 4B-Hog thyroglohulin affinity chromatography. The activity of the lectin was tested with fresh rabbit erythrocyte in each step of the procedure, and the active part was collected. This sample demonstrated single band on PAGE, SDS-PAGE and HPLC. The lectin was a glycoprotein. It contained 1.5% of neutral saccharide and its molecular weight was 63000 determined by Sephadex G-100 filtration. The N-terminal amino acid of the lectin was Val. The lectin showed no specific agglutination with any type of human erythrocytes. The hemagglutinaition activity could be inhibited by galactose and hog thyroglobilin, and depended on Ca2+, Mn2+, especially on Ca2+, not Mg2+. Its biological activity lost at 65 ℃ for S min. This lectin is used as a mitogen for human peripheral blood lymphocytes.