In vivo predegeneration of peripheral nerves: an effective technique to obtain activated Schwann cells for nerve conduits

In vivo predegeneration of peripheral nerves is presented as a convenient a nd effective method to obtain activated Schwann cells and an enhanced cell yield following in vitro cultivation. The experiments conducted in rats wer e aimed at clinical use in gaining Schwann cell suspensions for filling art ificial conduits in order to bridge peripheral nerve gaps. The rat sciatic nerve used as a model was transected distally to the spinal ganglia. Predeg eneration in vivo was allowed to take place for 1, 2, 3 and 4 days and up t o 1, 2 and 3 weeks. The nerve was then resected and prepared for cell culti vation. Schwann cells cultivated from the contralateral untreated nerve ser ved as control. Immunostaining for S100, nerve growth factor receptor and t he adhesion molecules N-cadherin and L1 was used to characterize the genera l state of the cultures. Viability was assessed by fluorescein fluorescence staining, and the proliferation index was determined by bromodeoxyuridine- DNA incorporation. The Schwann cells from predegenerated nerves revealed an increased proliferation rate compared to the control, whereas fibroblast c ontamination was decreased. Best results were obtained 1 week after predege neration. (C) 1999 Elsevier Science B.V. All rights reserved.