fig3

Figure 3. Exogen hair collection. Skin replicas were employed to observe the skin surface and monitor hair shafts with SEM (Scale bar = 50 µm, the upper right corner of A and B1-B2). The use of replica material is part of the exogen collection procedure and was employed only after the graft had firmly taken, beginning on D11. (A) shows the replica on D11, highlighting the skin surface microrelief. No hair fiber is present; instead, the typical surface of the hair shaft is visible (A1) above the exit point of the grafted follicle (dark spot, A2). This demonstrates that the hair shaft was securely anchored inside the grafted follicle; (B) shows the replica on D42, where the exogen hair shaft is now entrapped in the polymerized matrix. The shaft is visible from its exit point at the skin surface (B1) down to the root end (B2). The area outlined in red is further magnified in B2 (extreme right). The shape of the “normal” cortical cells is a result of sudden anagen arrest, followed by migration (without growth) until all intercellular junctions have been dissolved, i.e., no typical telogen clubbing. SEM: Scanning electron microscopy.