Culturing Human Schwann Cells
The method involved in the establishment of human adult Schwann cell cultures has steadily evolved over the last 20 yr. Unlike the more straightforward methods used with other species (e.g., rat), simple dissociation of human peripheral nerve tissue has been found to result in both very low cell yields and poor Schwann cell purity (1 ,2 ). This is thought to be caused by the increased amount of connective tissue within human nerves and the mechanical damage sustained by the tightly wrapped Schwann cell processes. These problems were previously overcome by the pioneering work of Askanas et al. in 1980 who developed a method involving the continual re-explantation of small segments of peripheral nerve tissue (explants) (3 ). The resulting cultures, derived from cells that had emigrated from the explants, were found to exhibit an increased Schwann cell purity upon successive re-explantations. The major drawback to this “re-explantation” method, however, was the length of time it took (months) to establish high-purity Schwann cell cultures.