Expression of the human poliovirus receptor/CD155 gene during development of the central nervous system: Implications for the pathogenesis of poliomyelitis

The gene for the human poliovirus receptor (hPVR/CD155) is the founding mem ber of a new family of genes encoding proteins belonging to the immunoglobu lin superfamily. To determine whether CD155 is expressed during mammalian d evelopment, we have made use of the previously characterized promoter of th e CD155 gene and generated mice transgenic for a CD155 promoter-driven P-ga lactosidase reporter gene. Expression of the reporter gene in transgenic em bryos was observed during midgestation in anterior midline structures of th e developing central nervous system and in the neuroretina. During that per iod, reporter gene expression appeared within the notochord and floor plate along the entire spinal cord reaching into the caudal diencephalon. In add ition, transgene expression was observed in axonal projections emanating fr om retinal ganglion cells forming the optic nerve to reach the future regio n of the optic chiasm. Analysis of expression of CD155 during human embryon ic development confirmed the distribution of reporter gene expression speci fied by CD155 promoter activity. The anatomical distribution of CD155 promo ter activity during embryogenesis matches that of transacting factors previ ously identified to regulate transcription of the CD155 gene. Expression of CD155 within embryonic structures giving rise to spinal cord anterior horn motor neurons may explain the restrictive host cell tropism of poliovirus for this cellular compartment of the CNS. (C) 2000 Academic Press.