Transverse sections through the spinal cord with adjacent transplant. Elongated tubes formed by bNCSCs (green) outside the spinal cord are associated with regenerating fibers (red) from different subpopulations of sensory neurons: IB4 (a), /RET (b), CGRP (c), RT97 (d). Note IB4 labeling of macrophages (a). Due to their undulating course, sensory axons appear in the thin sections as short segments (arrows) associated with eGFP-positive cells. Inserts a, b and d show details of the relationship between bNCSC forming tubes and the respective sensory axon subtypes. Scale bar: a = 50 μm, b = 100 μm, c = 25 μm, d = 100 μm; inserts: a = 50 μm, b = 50 μm, c = 25 μm, d = 50 μm;.