| Abstrakt: |
Gangliosides are implicated in cell signal transduction. Prior to investigating this phenomenon in macrophages, the accessibility of gangliosides to macromolecules was assessed for peritoneal macrophages isolated from normal C3H/HeN and endotoxin-hyporesponsive C3H/HeJ mice. C3H/HeJ resident and thioglycolate-elicited macrophage gangiioside patterns are the same as normal strains, and no strain differences in galactose oxidase accessibility for resident or thioglycolate-elicited macrophage gangliosides were found. The only gangliosides accessible to galadose oxidase in resident macrophages are G structures. In thioglycolate-elicited macrophages, an additional ganglieoside is accessible. For -activated macrophages, where ganglioside distribution differs between strains, a difference in galactose oxidase-accessible gangliosides also exists. -activated C3H/HeN patterns show three triplets absent in C3H/HeJ patterns. There were no differences in ganglioside accessibility to sialidase between the thioglycolate-elicited C3H/HeJ and C3H/HeN macrophages. However, despite differences in sialidase-sensitive ganglioside content between E.-activated macrophages of these strains, sialidase accessibility for -activated macrophages was also similar. Sialidase-susceptible G. was cryptic in either strain under all conditions examined. The accessibility of murine macrophage gangliosides to galactose oxidase or sialidase was independent of their sialic acid species and chain length of the ceramide fatty acid. With the exception of G, major murine macrophage gangliosides are accsdble to macromolecules, especially to exogenous pathogenic bacterial sialidase which can alter macrophage cell surface characteristics. Altered macrophage ganglioside accessibility appears sometimes as a consequence, but not a cause, of C3H/HeJ endotoxin hyporesponsiveness. [ABSTRACT FROM PUBLISHER] |
