[Clinical perspectives of xenografts: encapsulated chromaffin cells and pain]

Abstract

Intrathecal allograft of chromaffin cells can be effectively used in replacement of more conventional therapies for treating intractable chronic pain, such as in cancer. The efficacy of this technique depends on the ability of those cells to produce analgesic opioids and on the immuno-privileged property of the central nervous system, in which rejection risks are limited. However, there are some limitations to the generalization of this new therapy, mainly due to the low number of available grafts. Thus other sources than humans have to be considered. Here we discuss the pros and cons of the xenogeneic chromaffin cells of bovine or porcine origin. Graft immuno-isolation, for example, by using cell encapsulation, seems to be unavoidable in spite of the graft site.