Mitogenic effects of bacterial neuroaminidase and lactosylceramide on human cultured fibroblasts.
Exogenously added bacterial neuraminidase and lactosylceramide both stimulated the growth of cultured human skin fibroblasts. Neuraminidase (100 units/ml) increased DNA synthesis 1.9-fold and cell density 1.4-fold after 24 and 48 h, respectively, in culture. Treated fibroblasts contained less ganglioside NeuAc alpha 2-3Gal beta 1-4GlcCer (GM3), presumably due to neuraminidase-catalyzed hydrolysis to lactosylceramide. Addition of lactosylceramide (100 microM) to the fibroblast culture medium also increased DNA synthesis threefold within 24 h and cell density twofold after 48 h. These findings are compatible with a mechanism by which the proliferation of human fibroblasts is regulated by the relative levels of GM3 and lactosylceramide in the plasma membrane.
Ogura
K
K
Department of Biochemistry, Michigan State University, East Lansing 48824.
Sweeley
C C
CC
D015703:Antigens, CD; D002240:Carbohydrate Sequence; D002455:Cell Division / Q000187:drug effects*; D002478:Cells, Cultured; D004261:DNA Replication / Q000187:drug effects*; D005679:G(M3) Ganglioside / Q000378:metabolism*; D006028:Glycosphingolipids / Q000494:pharmacology*; D006801:Humans; D007790:Lactosylceramides; D008934:Mitogens / Q000494:pharmacology; D008969:Molecular Sequence Data; D009439:Neuraminidase / Q000494:pharmacology*
D015703:Antigens, CD; D005679:G(M3) Ganglioside; D006028:Glycosphingolipids; D007790:Lactosylceramides; D008934:Mitogens; C009744:CDw17 antigen; D009439:Neuraminidase