The hybrid cell line ND15 was derived after fusion of primary neonatal-rat dorsal-root-ganglion (DRG) neurons with N18Tg2, a mouse neuroblastoma (C1300)- derived azaguanine-resistant line. HAT-sensitive hybrids were selected and cloned by limiting dilution. The cells express all isoforms of N-CAM but no embryonic form. Thy 1.1 marker, P31 and PrPc can be detected as well as a weaker expression of F3 and Thy-3. When differentiated in serum free media an increased level of Thy-2 can be detected.