Résumé
Lectins from extracts of Phaseolus vulgaris seeds have potent cell-agglutinating and lymphocyte-stimulating activity. An affinity adsorbent for lectins with specificity for the oligosaccharide structure was prpared by transforming ovomucoid, an oligosaccharide-rich glycoprotein, into an insoluble and stable gel. The ovomucoid was made insoluble by boiling a 20 per cent solution (200 mg/ml) in 0.1 M Tris-HCl, pH 8.9, for 20 min. This insoluble gel was desialylated by treatment with 50 mN sulfuric acid for 1h at 90ºC and fixed with 1 per cent glutaraldehyde, pH 7,4, for 10 min. The Phaseólus lectin and the L4 isolectin could be isolated essentially in a single-step procedure, using different eluting conditions: 50 mM sodium formate buffer, pH 3,0, was used for PHA elutions; a different column was eluted with 15 mM sodium tetraborate, pH 8.0, for desorbed L4 isolectin. Polyacrylamide gel electrophoresis of the lectin showed five distinct bands, whereas the L4 isolectin only presented one band. From 250 mg of saturated column, 8.25 mg of PHA was isolated. This adsorbent could be used several times with little change in binding capacity or selectivity
Sujets)
Fabaceae/composition chimique , Lectines/isolement et purification , Phytohémagglutinine/isolement et purification , Chromatographie d'affinité , Électrophorèse sur gel de polyacrylamideRésumé
Mitogenic potential of the partially purified lectin from P. vulgaris isolated by ammonium sulphate precipitation was assessed by lymphocyte transformation test (LTT) and was compared with three commercially available phytohemagglutinins (PHA). The blast inducing capacity and mitotic index analysis revealed that this preparation has potential to be used in the indigenous commercial production of PHA which is routinely used for human chromosomal studies from the peripheral blood culture at, at present, is imported.
Sujets)
Relation dose-effet des médicaments , Fabaceae/composition chimique , Humains , Activation des lymphocytes , Lymphocytes/immunologie , Index mitotique , Phytohémagglutinine/isolement et purification , Lectines végétales , Plantes médicinalesRésumé
Phytohaemagglutinin obtained from P. vulgaris is a commonly used mitogen in lymphocyte cultures. The mitogenic potential of different cultivars of P. vulgaris vary. The present investigation encompasses the characterization of partially purified lectins from two varieties of P. vulgaris on the basis of their protein profile, lymphocyte transformation test by light and scanning electron microscopy and incorporation of radioactive thymidine.