Expression of membrane IGM by a human B lymphoblastoid cell line in the presence of monensin.

The effect of the carboxylic ionophore, monensin, on the synthesis and expression of membrane IgM in the human lymphoblastoid cell line, Daudi, was investigated. The normal processing events in the maturation of mu chains and k chains were altered in monensin treated Daudi cells; the immunoglobulin chains did not appear to undergo complete terminal glycosylation modifications. Transport of the glycoprotein to the plasma membrane could be demonstrated indicating that the interference of intracellular processing of the IgM by monensin did not significantly influence the membrane expression of the IgM.