The role of macrophages in bioartificial nerve grafts based on resorbable guiding filament structures.

A 10 mm gap in a rat sciatic nerve was bridged by a bioartificial nerve graft consisting of a silicone tube containing seven longitudinally placed filaments made of non-resorbable material (polyamide [Ethilon]) or resorbable materials (polydioxanon [PDS], polyglactin [Vicryl] or catgut). The purpose was to study the tissue reaction induced by the four different types of materials. At 4 weeks an immunocytochemical technique, using ED1 and ED2 monoclonal antibodies, was used to study the presence and location of macrophages. A large number of macrophages were found accumulating on the surface of catgut and polyglactin, while few were found on the surface of polyamide and polydioxanon filaments. It is concluded that the cell layers on the filament surface mainly consisted of ED1 positive cells and their thickness depends on the filament materials.