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Biomedical subjects

R E Billingham

Publications and source records attributed to R E Billingham.

At least 127 records · Page 7Linked to original sources
PubMed1967

Cutaneous hypersensitivity reactions to cellular isoantigens in rats.

Rats have been shown to be capable of displaying the various kinds of delayed cutaneous hypersensitivity reactions attributable to transplantation immunity previously described in guinea pigs, hamsters, rabbits, dogs, and man. The rat is unlike most other species in that much larger numbers of lymphoid cells are needed to incite these cutaneous reactions. With direct, transfer, or normal lymphocyte transfer reactions, the cutaneous responses were greater when donor and recipient differed at the Ag-B histocompatibility locus than when donor and recipient shared the same Ag-B alleles. An experiment was performed in which adult rats of a genetically defined backcross population, resulting from matings between DA and (DA x Lewis) F(1) hybrid rats, were inoculated intradermally with lymph node cells from DA rats sensitized against tissues from Lewis-strain donors. Some of the R(2) animals gave a biphasic transfer reaction with peak reactivities occurring first at 48 hr and recurring at 96-120 hr, while the others lacked this second component. Hemagglutination tests revealed that the R(2) rats giving the biphasic response possessed the Ag-B,1 antigen, which is also present in Lewis rats, whereas rats which gave monophasic reactions were homozygous for the Ag-B,4 antigenic determinant which is present in the DA strain. This suggested that the recall flare at 96-120 hr reflects proliferative activity on the part of the inoculated cells confronted by the disparate Ag-B isoantigen in the host's dermis. Skin homografts from R(1) animals bearing the Ag-B,1 antigen were uniformly rejected by DA hosts in 11 days or less, while grafts from backcross animals homozygous for the Ag-B,4 antigen usually lived longer, being rejected in 9 to 27 days. Evidence is also presented which suggests that specific isoantibodies may act synergistically with immune lymphocytes to bring about cutaneous inflammatory reactions in the rat.

Animals↗
PubMed1967

Studies on the conservation of epidermal specificies of skin and certain mucosas in adult mammals.

To determine whether the factor(s) responsible for the conservation of epidermal specificities in adult guinea pigs and hamsters resides in the germinal layer of the epidermis or in the dermis, thin grafts of skin, possessing qualitatively distinct regional characteristics, were separated into their superficial epidermal and dermal components with the aid of trypsin. Dermis of one type was combined with epidermis of another to produce "recombinant" grafts which were then transplanted to small, full thickness cutaneous sites on the thorax of geneticaily compatible hosts. A variant of this procedure involved transplanting sheets of superficial epidermis of various types to shallow split thickness recipient areas in the skin of the thorax. All grafts were maintained for 100 days before they were excised and examined histologically. The results indicate that, whereas the dermis determines the kind of epidermis produced in recombinant grafts involving the ear, the sole of the foot, and the trunk, this is not the case in recombinants which include tongue, esophageal, or cheek pouch epithelia. The one exception to this occurred when tongue or esophagus epithelia were transplanted to split thickness beds in trunk skin. Here they appeared to produce an epidermis characteristic of their new location. It is believed that this exception is probably due to the fact that the native follicular epidermis present in trunk dermis made such a substantial contribution to the new superficial epidermis that it behaved overtly as body skin epidermis. Taken together, these results suggest that basal layer cells of the superficial epidermis of sole of foot skin, ear skin, and the hair-bearing skin of the general integument behave as if they are equipotential, and that in adult life maintenance of these particular epidermal specificities is the outcome of persistent specific inductive stimuli from the underlying dermis. The results of subsidiary experiments are reported which indicate that the epithelial component of mammary gland tissue is also pluripotential, being capable of producing, under appropriate conditions, a normal-looking, fully stratified superficial epidermis.

Animals↗
PubMed1966

Studies on delayed cutaneous inflammatory reactions elicited by inoculation of homologous cells into hamsters' skins.

The intracutaneous inoculation of lymph node cell suspensions from normal hamsters into normal, homologous hosts causes the development of delayed inflammatory reactions, normal lymphocyte transfer (NLT) reactions, the intensities of which reflect the antigenic disparity between donor and recipient. The immunogenetic situations in which they occur indicate that these reactions are due to sensitization in situ on the part of inoculated immunologically competent cells against alien antigens of the host. They are graft versus host reactions. If hamsters are sensitized by cellular or solid tissue homografts and then challenged intracutaneously with lymphoid or epidermal cells from the donor strain, direct reactions are provoked. A positive correlation exists between the development of transplantation immunity and the capacity to give direct reactions. The sensitivity responsible for direct reactions can be suppressed by irradiation or administration of cortisone, and it is transferable by means of viable lymphoid tissues or cells but not by means of serum. Intracutaneous inoculation of viable node or splenic cells from specifically sensitized hamsters into hosts of the donor strain incites transfer reactions, the intensities of which depend upon the number of cells transferred and the level of sensitivity in the animal that provided them. These reactions are not incitable by thymocytes, by killed lymphoid cells, or by serum. Transfer reactions differ from NLT reactions only on a quantitative and chronologic basis. However, a sharp experimental distinction can be drawn between them. For example, if normal MHA node cells and node cells from MHA hamsters sensitized against CB antigens are injected into the skins of MHA's tolerant of CB tissue, only the sensitized cells incite reactions. Both direct and transfer reactions are highly specific immunologically. The inability of node cells to incite NLT or transfer reactions in heavily irradiated hosts and other findings sustain the thesis that it is host cells of hematologic origin, rather than indigenous skin cells, that contribute the antigenic stimulus required for these reactions. All the findings presented are consistent with the hypothesis that the various delayed inflammatory reactions described are manifestations of immunological responses on the part of immunologically competent cells against alien transplantation antigens.

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