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R E Billingham

Publications and source records attributed to R E Billingham.

At least 55 records · Page 3Linked to original sources
PubMed1981

The ultrastructure of grafted neonatal ovaries.

An ovary from a syngenic newborn donor was grafted into each ear of 9 ovariectomized and 3 intact adult female DA strain rats. Cycling resumed in ovariectomized animals after an average interval of 24 days. The average duration of the resumed cycles was 6 days. The histology and ultrastructure of grafted ovaries are compared with those of normal ones. Thecal cells became luteinized in grafted ovaries. The ultrastructure of interstitial tissue cells from grafted ovaries reflects increased specialization for steroidogenesis.

Animals↗
PubMed1980

Exchange of skin grafts among monozygotic quadruplets in armadillos.

Skin grafting experiments, with long-term follow-ups, on three litters of armadillo quadruplets born in our laboratory have confirmed the familiar rule that grafts exchanged between monozygotic littermates are not rejected as a consequence of alloimmune reactions. A possible explanation of the striking discrepancy between the present findings and those of a previous study is uncertainty about the relationships of the previous animals, which were obtained from a commercial dealer at 10 days of age.

Animals↗
PubMed1979

The lymphatic drainage of the rat prostate and its status as an immunologically privileged site.

Recent suggestions that the rat prostate is an alymphatic, immunologically privileged site stimulated further investigation of its status using a variety of techniques. Fixation of certain organs by vascular perfusion of glutaraldehyde followed by plastic embedding avoids the distortion and stromal reorganization that often obscures evidence of lymphatic vessels in conventional histological preparations. When applied to the rat prostate, this technique revealed small lymphatic vessels at irregular intervals throughout the sparse stroma. Ink injected into the prostate drained from the organ into iliac lymph nodes within 3 to 4 hr. Enlargement of iliac lymph nodes within 1 week after injection of parental strain lymphoid cells into the prostate of F1 rats confirmed the drainage pattern. Ink and lymphoid cell injections into the bladder wall yielded comparable results, although ink reached iliac nodes sooner than it did in prostate injections. Immunological privilege was investigated by determining survival of skin allografts implanted in the prostate. Skin-into-prostate grafts bearing either major or minor histocompatibility antigens were rejected within a few days of similar orthotopic grafts. The inability of the rat prostate to allow significantly prolonged allograft survival as well as its demonstrated lymphatic drainage argues against an immunologically privileged status.

Animals↗
PubMed1979

Privileged status of the subcutaneous site for skin allografts in rats.

Evidence is presented that in rats the subcutaneous site can extend privilege to both major histocompatibility complex (MHC)-incompatible (FI X DA)F1 leads to FI and MHC-compatible LEW leads to FI skin allografts, approximately doubling the median survival time of similar grafts transplanted orthotopically. Unlike graft dosage, "gene" dosage was an important variable in that grafts from (FI X DA)F1 donors significantly outlived those from DA strain donors. Prior splenectomy of the hosts did not prejudice the capacity of their subcutaneous sites to extend privilege. It was found that the hemagglutinin response incited by subcutaneous grafts was significantly delayed compared with that evoked by similar grafts transplanted orthotopically or intraperitoneally. This observation, coupled with our inability to demonstrate the passage of India ink to regional lymph nodes after its injection into the dermis of established subcutaneous grafts of syngenic skin, is consistent with the concept that poor endowment of the subcutaneous milieu with both blood and lymph vessels is the principal factor underlying its hospitality to allografts.

Animals↗
PubMed1978

Adipose tissue, a neglected factor in aetiology of breast cancer?

The abundant adipose tissue that intimately invests both the alveolar and the ductal epithelium of the mammary gland may function as a slow-release depot for lipid-soluble carcinogenic agents of both endogenous and exogenous origin taken up from the bloodstream.

Adipose Tissue↗
PubMed1978

Maternal immunological recognition mechanisms during pregnancy.

One of the most intriguing shortcomings of modern immunology, especially transplantation immunology, is its failure to provide a satisfactory final explanation for the consistent non-rejection of immunogenetically alien conceptuses in utero, even in specifically preimmunized females. Certainly, there is no shortage of hypotheses. Over the past few years various observations have utterly refuted the simplistic notion that the much-mated but nulliparous or gravid females are immunologically unaware of the presence and activities of allogeneic cells transiently or chronically within their reproductive tracts. This evidence has engendered the belief that some kind(s) of active response(s) on the part of the female, following early recognitive events, plays an important, if not essential, role, in conjunction with adaptive hypoantigenicity of the trophoblast, not only in conferring selective benefits upon the conceptus from the time of implantation, but also in affording it protection from the possible hazards of a cellular immunity. Evidence is emerging that during mating, implantation, placentation, and gestation (1) various fetal and histocompabibility antigens are presented to the mother in a unique manner; (2) she does respond to these; and (3) her responses aid in the establishment and maintenance of a harmonious state of immunological coexistence with her fetus. There are reasonable grounds for believing that a complete understanding of the immunobiology of the maternal-fetal relationship may facilitate significant advances in both transplantation and tumour immunology.

Animals↗