IFRS1 cells display distinct Schwann cell phenotypes, such as spindle-shaped morphology with intense immunoreactivity for glial cell markers, synthesis and secretion of neurotrophic factors, and fundamental ability to myelinate neurites in co-culture with adult rat DRG neurons [12], NGF-primed PC12 cells [14], NSC-34 mouse neuroblastoma/embryonic spinal motor neuron hybrid cells [15,16] and ND7/23 mouse neuroblastoma/rat embryonic DRG neuron hybrid cells [17] (Takaku et al., in preparation). Here, NGF is linked to neuroblastoma.