Although gland function may be expected to follow endocrine autotransplantation in the majority of instances, unmodified endocrine allografts appear to undergo immunologic rejection within 8 to 14 days without ever giving clear evidence of function. An exception to this course of events has been suggested by Medawar,1 who first demonstrated in rabbits that allografts ectopically implanted into certain "immunologically privileged sites," such as the anterior chamber of the eye or the brain, will frequently survive, presumably because of the scant supply of lymphatics to these areas and resultant modification of the characteristic rejection reaction. Although there are conflicting reports regarding the ability of "privileged sites" to permit prolonged survival and function after allogeneic thyroid implantation1-3; neither of the sites that have been studied is of practical significance for clinical ap plication, and they have served primarily as investigational models.
In the present study the marrow space of rabbit
Fonkalsrud EW. Thyroid Allografts Implanted in the Marrow Space of RabbitsA Functional and Morphological Evaluation. Arch Surg. 1969;98(6):738-741. doi:10.1001/archsurg.1969.01340120086013