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G M Troup

Publications and source records attributed to G M Troup.

11 recordsLinked to original sources
PubMed1978

Effects of whole-body irradiation on neonatally thymectomized mice. Incidence of benign and malignant tumors.

The individual and combined effects of neonatal thymectomy and whole-body irradiation on the prevalence of benign and malignant tumors in germ-free female mice of the Charles Rivers line were studied to determine if a portion of the tumorigenic effects of irradiation can be attributed to injury of the thymic-dependent component of the immune response. Neonatal thymectomy increased a) the incidence of benign and malignant tumors and b) the prevalence of multiple primary neoplasms in an individual mouse. Whole-body exposure to 700 rad at 6 weeks of age further increased th incidence of tumors, but the relative magnitude of this increase was less pronounced than in sham-operated controls. Thus, the cumulative effects of thymectomy plus irradiation are less pronounced than the sum of the individual effects. One of several possible explanations for this observation is that a portion of the carcinogenic effects of whole-body irradiation is mediated by suppression of the thymic-dependent component of the immune response.

Animals↗
PubMed1978

Studies of HLA alloantigens of the Navajo Indians of North America. I. Variance of association between HLA-DRW (WIA) and HLA-DW specificities.

As a part of the 7th International Histocompatibility Workshop, 49 randomly selected Navajo Indians were B-cell (DR) typed. Thirty-three of these individuals were also HLA-D (L.D.) typed with the Caucasian derived Copenhagen homozygous testing cell panel. DRW 2, 7, and WIA 8 were clearly defined while DRW 3 and 4 were less well defined and DRW 1, 5, and 6 were not defined in this population by the Workshop antisera. There was highly significant correlation between DRW 7/DW 7 and WIA 8/DW 8 but no correlation at all between DRW 2/DW 2, DRW 3/DW 3 and DRW 4/DW4. These results, in part, were discordant with the finding of the 7th Workshop and suggest that either DRW (WIA) and DW alloantigens are the product of more than one gene locus or that these antigens are a product of one gene locus but that each antigen molecule has multiple factors.

B-Lymphocytes↗
PubMed1977

Radiosensitivity of T and B lymphocytes. IV. Effect of whole body irradiation upon various lymphoid tissues and numbers of recirculating lymphocytes.

Groups of 10-week-old female CBA/J mice were exposed in whole body fashion to 0,5,50, and 500 rads and sacrificed in serial fashion 1,3,5,7,9,15, and 30 days after irradiation for morphologic evaluation of thymus, spleen, lymph node, and Peyer's patch, and assessment of the relative numbers of thymus-derived (T) and bone marrow-derived (B) cells in these tissues. The absolute and relative numbers of recirculating T and B cells mobilizable by thoracic duct cannulation were also determined and compared with similar determinations with respect to peripheral blood lymphocytes. B cell depletion occurred more quickly and was more pronounced in spleen and lymph node than T cell depletion at all three exposure doses. Depletion of T and B cells was roughly equal in peripheral blood and thoracic duct lymph. When present, regeneration of the T cell component occurred more rapidly than did B cell restoration. The latter often was incomplete at the time of the final sacrifice (day 30). PHA-responsive and Con A-responsive cells also appeared to differ with respect to the kinetics of cell death after whole body irradiation.

Animals↗
PubMed1977

Antilymphocyte antibodies in systemic lupus erythematosus: familial clustering of lymphocyte antigens.

Cold reactive lymphocytotoxic sera from patients with systemic lupus erythematosus and their relatives were found to react with lymphocyte antigens that cluster in normal families. These antigens do not correlate with HLA-A or -B antigens in families, suggesting that they are not related to Ir genes. Further work is indicated to determine whether these antigens are controlled by several genes or involve viral products on the cell surface.

Antigens↗
PubMed1976

The merrit alloantigenic system of human B lymphocytes: evidence for thirteen possible factors including one six-member segregant series.

An analysis of the typing results of a 70-member chronic lymphatic leukemia B cell panel revealed evidence for 13 possible groups of the Merrit alloantigenic system. Six of these appeared possibly allelic and may represent a segregant series. The CLL panel was also fully typed for HLA and some degree of linkage dysequilibrium between Merrit and HLA seemed apparent from the data. Merrit antibodies can be absorbed out with selected surface membrane immunoglobulin (SMIG)-positive normal lymphocytes and less so or not at all with E rosette-forming T cells or Fc-positive SMIG-negative lymphocytes.

Absorption↗
PubMed1975

Sea-blue histiocytes and sural nerve in neurovisceral storage disorder with vertical ophthalmoplegia.

Ultrastructural investigation of bone marrow histiocytes in neurovisceral storage disorder associated with vertical ophthalmoplegia revealed 3 types of cytosomes: (1) lamellar cytosomes; (2) larger cytosomes composed of lamellar fragments and a granular component; and (3) large irregular cytosomes with amorphous and granular portions, often including fingerprint profiles--in some of these, lysosome-like bodies were numerous. The lamellar cytosomes corresponded to vacuoles seen by light microscopy. The Type 2 and 3 cytosomes were the ultrastructural substract of Wright-Giemsa stained blue granules. Histiocytes having a predominance of Type 2 cytosomes in a cytoplasm rich in free ribosomes had the appearance of sea-blue histiocytes at the light-microscopic level. Transformed Type 1 cytostomes served as building blocks for Type 2 and 3 cytosomes. In the sural nerve, Schwann cells and endoneurial fibroblasts accumulated autofluorescent lipopigment but no lamellar cytosomes or their fragments were found on electron-microscopic examination. Ultrastructure of sea-blue histiocytes in this disease differed from that observed in some other diseases.

Adult↗
PubMed1975

Radiosensitivity of sensitized and nonsensitized human lymphocytes evaluated in vitro.

The purpose of this study is to compare the relative radiosensitivity of sensitized and nonsensitized lymphocytes utilizing an in vitro test system. The test system employed is the combined mixed leukocyte reaction and cell-mediated lympholysis assays (MLC-CML). In this system, sensitized T lymphocytes of human origin are much more resistant to radiation-induced injury than are nonsensitized lymphocytes. The results support similar observation in vivo with antigen-activated lymphocytes and are interpreted in one of two ways: a) sensitized T cell, rendered nonviable by radiation, are still able to exert lytic activity, perhaps via the release of cytotoxic factors; and b) sensitized T cells are inherently radioresistant, perhaps due to the hypermetabolic state of such cells, which may serve to activate repair mechanisms.

Animals↗