The brain and subarachnoid space as possible sites for endocrine tissue transplantation.

Immunological rejection has been the major problem limiting the successful transplantation of tissue from one animal to another. Recent technological developments, combined with the use of the central nervous system as an immunologically privileged site, suggest that it might be possible to achieve long-term survival of hormone-secreting tissues, between two gentically dissimilar animals, if these tissues are transplanted to the brain and subarachnoid space of the host. The physiological parameters that should be considered in the clinical application of a transplant of this type are discussed.