title: Ganglioside GM1 antibodies and B-cholera toxin bind specifically to embryonic chick dorsal root ganglion neurons but do not modulate neurite regeneration.
abstract: Polyclonal antibodies to ganglioside GM1 have been prepared and characterised by direct and competitive enzyme-linked immunoassay. An immunoglobulin fraction was prepared from a rabbit antisera showing high specificity and antibody titre for GM1 relative to the other major brain gangliosides. The anti-GM1 immunoglobulin fraction and B-cholera toxin specifically labelled neurons in primary cultures of embryonic chick dorsal root ganglia and there was a good correlation between the relative increase in binding of anti-GM1 immunoglobulin and B-cholera toxin following neuraminidase treatment of a variety of cell types. At antibody concentrations that show saturable binding to endogenous ganglioside in the neuronal membrane, the anti-GM1 immunoglobulin fraction did not interfere with the nerve growth factor (NGF)-mediated fibre outgrowth and neuronal survival as indexed by measurement of neurofilament protein levels. Similarly, at levels in excess of those shown to stimulate thymocyte proliferation, B-cholera toxin was also without effect. These data are not consistent with GM1 in the neuronal membrane functioning as a receptor molecule for NGF and/or other differentiation factors present in the tissue culture media.
mesh_terms: D000818:Animals; D000906:Antibodies / Q000276:immunology; D000918:Antibody Specificity; D001369:Axons / Q000502:physiology*; D001667:Binding, Competitive; D002455:Cell Division / Q000187:drug effects; D002642:Chick Embryo; D002772:Cholera Toxin / Q000378:metabolism* / Q000494:pharmacology; D005677:G(M1) Ganglioside / Q000276:immunology / Q000502:physiology*; D005727:Ganglia, Spinal / Q000196:embryology / Q000378:metabolism*; D007136:Immunoglobulins / Q000276:immunology / Q000378:metabolism; D007381:Intermediate Filament Proteins / Q000378:metabolism; D009414:Nerve Growth Factors / Q000494:pharmacology; D009416:Nerve Regeneration; D009439:Neuraminidase / Q000494:pharmacology; D009474:Neurons / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D000906:Antibodies; D007136:Immunoglobulins; D007381:Intermediate Filament Proteins; D009414:Nerve Growth Factors; D005677:G(M1) Ganglioside; D002772:Cholera Toxin; D009439:Neuraminidase