Glycosidase inhibitors (castanospermine and swainsonine) and neuraminidase inhibit pokeweed mitogen-induced B cell maturation.
Castanospermine (CSP), an inhibitor of alpha-glucosidase, enhanced immunoglobulin (Ig) release in a Staphylococcus aureus Cowan I (SAC)-induced lymphocyte culture (Scand. J. Immunol. 1990. 32: 529). In a pokeweed mitogen (PWM)-human lymphocyte culture, unlike the SAC-stimulated system, CSP strongly decreased the number of IgG-, IgA- and IgM-secreting cells as well as that of Ig-bearing cells. Peripheral blood lymphocytes treated with swainsonine, a mannosidase II inhibitor, or with neuraminidase also showed a reduced response to PWM. In cross-culture experiments, only a mixture of B cells pretreated with either agent and untreated T cells showed such a suppressive effect. Adhesion was decreased between B cells treated with either agent and untreated T cells, but not between treated T cells and untreated B cells. These results demonstrate that a certain alteration in B cell membrane oligosaccharides inhibited the T cell-B cell adhesion in the PWM culture, leading to an arrest of B cell maturation. Considering that these inhibitors eventually prevent terminal sialic acid addition, the present study provides evidence that sialic acids on B cell surface oligosaccharides play a biological role in the T cell-B cell interaction.
Karasuno
T
T
Second Department of Internal Medicine, Osaka University Medical School, Japan.
Kanayama
Y
Y
Nishiura
T
T
Nakao
H
H
Yonezawa
T
T
Tarui
S
S
D001402:B-Lymphocytes / Q000187:drug effects* / Q000502:physiology; D002450:Cell Communication; D002478:Cells, Cultured; D065089:Glycoside Hydrolase Inhibitors; D006801:Humans; D007212:Indolizines / Q000494:pharmacology*; D008562:Membrane Glycoproteins / Q000032:analysis; D009439:Neuraminidase / Q000494:pharmacology*; D009844:Oligosaccharides / Q000032:analysis*; D011043:Pokeweed Mitogens / Q000378:metabolism; D017026:Swainsonine / Q000494:pharmacology*; D013601:T-Lymphocytes / Q000502:physiology; D054836:Indolizidines
D065089:Glycoside Hydrolase Inhibitors; D007212:Indolizines; D008562:Membrane Glycoproteins; D009439:Neuraminidase; D009844:Oligosaccharides; D011043:Pokeweed Mitogens; D017026:Swainsonine; C037806:castanospermine; D054836:Indolizidines