NEURONAL CELL-SURFACE MOLECULES MEDIATE SPECIFIC BINDING TO RABIES VIRUS GLYCOPROTEIN EXPRESSED BY A RECOMBINANT BACULOVIRUS ON THE SURFACES OF LEPIDOPTERAN CELLS

The existence of specific rabies virus (RV) glycoprotein (G) binding s ites on the surfaces of neuroblastoma cells is demonstrated. Spodopter a frugiperda (Sf2l) cells expressing G of the RV strain CVS (Gcvs-Sf21 cells) bind specifically to neuroblastoma cells of different species but not to any other cell type (fibroblast, myoblast, epithelial, or g lioma). Attachment to mouse neuroblastoma NG108-15 cells is abolished by previous treatment of Gcvs-Sf21 cells with anti-G antibody. Substit utions for lysine at position 330 and for arginine at position 333 in RV G greatly reduce interaction between Gcvs-Sf2l cells and NG108-15 c ells. These data are consistent with in vivo results: an avirulent RV mutant bearing the same double mutation is not able to infect sensory neurons or motoneurons (P. Coulon, J. P. Ternaux, A. Flamand, and C. T uffereau, J. Virol. 72:273-278, 1998) after intramuscular inoculation into a mouse. Furthermore, infection of NG108-15 cells by RV but not b y vesicular stomatitis virus leads to a reduction of the number of bin ding sites at the neuronal-cell surface. Our data strongly suggest tha t these specific attachment sites on neuroblastoma cells represent a n euronal receptor(s) used by RV to infect certain types of neurons in v ivo.