Gangliosides in Nervous Tissue Cultures and Binding of ¹²⁵i‐labelled Tetanus Toxin, a Neuronal Marker

Abstract— —Continuous cell lines, primary cell cultures derived from embryonic CNS, and homogenates made from adult and embryonic CNS were compared with respect to their lipid pattern and their ability to bind 125 I‐labelled tetanus toxin. In parallel experiments de novo synthesis of gangliosides in the cell lines was studied, using [ 14 C]glucosamine as precursor. Of the total lipid only gangliosides were specifically labelled by [ 14 C]glucosamine. The patterns of the de novo synthesized gangliosides corresponded to those present in the respective cells. Pronounced binding of 125 I‐labelled toxin was only detectable in tissues containing long‐chain gangliosides (ganglioside C which represents GDIb and GTI). Accordingly, hybrid (neuroblastoma x glioma) cells, due to their lack of long‐chain gangliosides, bound just‐discernible amounts of labelled toxin. When previously exposed to gangliosides, their binding of tetanus toxin tremendously increased. It was concluded that only the long‐chain gangliosides in the neuronal cells are functionally involved in the binding of the tetanus toxin and that these acceptors of tetanus toxin can be transplanted.