Studies on nonidet P40 lysis of murine lymphoid cells. I. Use of cholera toxin and cell surface Ig to determine degree of dissociation of the plasma membrane

Abstract

Lymphoid cells from A/J mice were iodinated (125I) by the lactoperoxidase lysed with the non-ionic detergent NP-40. The plasma membrane glycolipid receptor for cholera toxin and cell surface immunoglobulin were utilized in immune precipitation systems to characterize the degree of dissociation of the plasma membrane under various conditions. It was found that at 0.1% NP-40 and at cell concentration from 5 to 10 times 10(7) cells/ml, lipid-protein and protein-lipid-protein complexes formed in NP-40 which were soluble after centrifugation at 10(5) times G. Column chromatography of 125I-cell lysates on agarose A-0.5 M in 0.1% or 0.5% NP-40/PBS indicated that the majority of iodinated cell surface material existed as aggregates in detergent micelles. The availability of the oligosaccharide moiety of the glycolipid to interact with the cholera toxin was dependent on both the detergent concentration and the cell concentration used for cell lysis. However, the cell surface immunoglobulin was immunoprecipitable under all conditions of lysis tested.