Molecular basis of B cell activation: mitogenicity of native and modified digitalis glycosides.
Lanatoside C, a digitalis glycoside, has previously been shown to be a potent polyclonal B cell activator for mouse lymphocytes. Since the chemical structure of lanatoside C is well defined we investigated the effect of different chemical modifications on the mitogenic properties of the glycoside in order to determine the molecular basis of B cell activation. The presence of an OH- group at C12 in the steroid nucleus proved to be essential for activation to occur in serum-free medium. Likewise, an intact carbohydrate side chain at C3 appeared to be necessary for retaining mitogenic properties. In serum-supplemented cultures, however, a much more complex response pattern was observed where the prerequisites for activation were not as distinct as in serum-free medium.
D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D050260:Carbohydrate Metabolism; D002244:Carbon / Q000378:metabolism; D003470:Culture Media; D004071:Digitalis Glycosides / Q000494:pharmacology*; D005260:Female; D007799:Lanatosides / Q000494:pharmacology; D008213:Lymphocyte Activation; D008297:Male; D051379:Mice; D008805:Mice, Inbred A; D008808:Mice, Inbred CBA; D008934:Mitogens
D003470:Culture Media; D004071:Digitalis Glycosides; D007799:Lanatosides; D008934:Mitogens; D002244:Carbon