AFFINITY CHROMATOGRAPHY OF A MYELOMA IMMUNOGLOBULIN-M AND ITS TRYPTIC FAB AND (FC)5 FRAGMENTS USING LECTINS COVALENTLY COUPLED TO SEPHAROSE-4B

The mannose-specific lectin Concanavalin A and the galactose-specific Ricinus communis lectin were used as immobilized Sepharose 4B conjugates for the purification of IgM amd (Fc)5 and for the separation of Fab from (Fc)5. No significant differences were found in the interaction of the two Sepharose-lectins with IgM and its tryptic Fab and (Fc)5 fragments. Up to 30% of proteins in stored IgM preparations were not bound to Sepharose-lectins. It was shown that the non-bound material has low mol. wt protein contaminants. Whereas (Fc)5 was bound to both types of lectin conjugate. Fab. even after pretreatment with 2% SDS, was not bound. The difference in binding properties between both types of fragment was utilised to fractionate them by means of affinity chromatography on Ricinus lectin-Sepharose. Fab poor in carbohydrate interacted with Con A-Sepharose, but not with Ricinus lectin-Sepharose. © 1979.