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Biomedical subjects

R J Scothorne

Publications and source records attributed to R J Scothorne.

36 records · Page 2Linked to original sources
PubMed1977

Extended survival of pancreatic islet allografts in the testis of guinea-pigs.

1. Pancreatic islets, isolated from the guinea-pig pancreas by microdissection and transplanted as allografts to the testis, may survive for 11 weeks, some 5 times the maximum survival of orthotopic skin grafts. 2. Intratesticular islet cell allografts appear not to provoke a systemic immunity such as might be detected by the behaviour of a subsequent orthotopic skin allograft from the same donor. 3. Intratesticular islet cell allografts succumb (in 'second set' fashion) to a pre-existing immunity generated by a prior orthotopic skin allograft. 4. Further experimental work is necessary to determine the relative importance of graft dosage, graft antigenicity, graft site and 'graft adaptation' in determining this extended survival.

Animals↗
PubMed1977

Further studies on the transplantation of isolated pancreatic islets.

It is concluded that the extended survival of allografts of isolated pancreatic islets in the testis and in the omentum is probably due to several factors. 1. An element of 'privilege' in both graft sites, of unknown nature. 2. The small amount of tissue transplanted. 3. Weaker antigenicity of ancreatic islet tissue as compared with that of skin.

Animals↗
PubMed1975

The fate of heterotopic isografts and allografts of mouse yolk sac epithelium.

As a contribution to the problem of the immunological privilege of the fetus it was decided to investigate the fate of yolk sac grafts in mice. Ten-day post-coitum mouse visceral yolk sac was transplanted to a dermal tunnel in the flank of isogeneic animals. In this site the yolk sac was capable of surviving for at least 15 days past the normal duration of pregnancy. Yolk sac was transplanted to a similar site in allogeneic animals and was found to be destroyed by an immunological reaction within 13 days. Orthotopic skin grafts between the same strains of mice used in the yolk sac transplantation were rejected in first-set fashion within 13 days. A limited series of host animals, previously sensitized by visceral yolk sac, rejected orthotopic skin grafts in second-set fashion. These findings indicate that the cells of the visceral yolk sac in the mouse contain transplantation antigens. Possible reasons why such antigens do not lead to fetal rejection during pregnancy are considered.

Animals↗
PubMed1975

An electron microscopic study of the histogenesis of the parathyroid gland in the sheep.

Definitive chief cells, characterized by the presence of specific secretory granules and typical membrane configurations, were present in the developing parathyroid glands of sheep embryos from 26 days of gestation (term = 150 days). During earlier stages of gestation developing chief cells contained lysosomal systems which appeared to be concerned with the autophagy of retained secretion product. The EM evidence suggests that physiologic release of the hormone does not occur until at least 30 days of gestation, which correlates well with the experimentally established time of onset of functional capacity in the parathyroid gland in the sheep. 'Bark cells' were found in the parathyroid primordia of embryos between 20 and 27 days of gestation. The significance of these "dark cells" is discussed with respect to glutaraldehyde fixation and to their possible relationship to chief cells.

Animals↗