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J Boniver

Publications and source records attributed to J Boniver.

At least 145 records · Page 8Linked to original sources
PubMed1988

Distribution of Lyt antigens on the surface of thymocytes associated with thymic macrophages and dendritic cells.

Thymocyte subpopulations that are associated with macrophages and dendritic cells of the thymus in vivo were isolated from the thymuses of C57B1/6 mice, and their Lyt phenotypes were analyzed. Electron-microscopic examination of immunogold-labeled cells revealed that the thymic complexes formed by macrophages mainly contained Lyt-2-positive thymocytes, while Lyt-1-positive thymocytes were more frequently associated with dendritic cells. The characteristic distributions of Lyt antigens on the surface of thymocytes in regions of reciprocal contact with macrophages (Lyt-2-positive cells) and dendritic cells (Lyt-1-positive cells) suggest that these antigens play a role in specific interactions between thymocytes and stroma cells.

Animals↗
PubMed1988

The neurohormonal thymic microenvironment: immunocytochemical evidence that thymic nurse cells are neuroendocrine cells.

Thymic neuroendocrine cells were identified by immunofluorescence in the murine thymus through the use of monoclonal antibody A2B5, and specific polyclonal antisera against neurophysin (NP), oxytocin (OT) and arginine vasopressin (AVP). Two reactive regions were clearly identified: the subcapsular cortex and the medulla. A close correspondence was observed between A2B5-reactive and NP-immunoreactive cells in the medulla. An important epithelial population of the subcapsular cortex, the thymic nurse cells (TNCs), were found to be A2B5-positive and to contain immunoreactive NP, OT and AVP. The neuroendocrine nature of TNCs was further substantiated by their high reactivity with an antiserum against neuron-specific enolase. These observations demonstrate the presence in the thymus gland of an original neuroendocrine microenvironment which could be of functional importance in the mediation of central influences upon T lymphocyte differentiation.

Animals↗
PubMed1988

Mammosomatotropes in human pituitary adenomas as revealed by electron microscopic double gold immunostaining method.

Hormone production was studied in situ by immunocytochemical methods in 20 pituitary adenomas. Special attention was given to 13 adenomas removed from acromegalic patients. Out of them, 6 had mild to moderate hyperprolactinemia. Immunohistochemistry revealed PRL-containing cells without any close relationship with high PRL serum level in 6 patients. Double immunogold staining revealed mammosomatotrope cells characterized by simultaneous presence of GH and PRL in the same granules in 2 patients. Since mammosomatotropes have never been demonstrated in the normal pituitary, our results probably signify gene dysregulation in pituitary cells of those acromegalic patients.

Adenoma↗
PubMed1988

Serum beta 2-microglobulin levels in chronic post-transfusion non A non B liver disease.

Serum beta 2-microglobulin (beta 2 mu), a reliable marker of T-cell activation, was measured in 25 patients with chronic post-transfusion non A non B (NANB) liver disease and in 21 patients with HBsAg positive chronic liver disease. beta 2 mu levels were elevated in NANB patients when compared with controls but not in comparison with the HBsAg carriers. In NANB patients, beta 2 mu concentrations were significantly correlated with serum IgG (P less than 0.001) and with circulating immune complex activity, assessed by the 125IClq binding test (P less than 0.01). These findings suggest that, in addition to T-cells, the B-cells contributed also to the beta 2 mu production. Patients with "active disease" (chronic active hepatitis and active cirrhosis) had significantly higher beta 2 mu levels (P less than 0.001) than did those with "inactive disease" (chronic persistent hepatitis and inactive cirrhosis). This relation of serum beta 2 mu concentrations and histological activity was also observed in the HBsAg carriers and suggests that the course of post-transfusion NANB chronic hepatitis could be determined by host's immune response rather than by a direct effect of the virus.

Adult↗
PubMed1988

Enzyme analysis of thymic nurse cells.

Thymic nurse cells (TNC) were characterized according to their enzyme content. The following enzymes: Lactate dehydrogenase (LDH) isoenzymes, adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP) were evaluated. When the enzyme profile of the TNC were compared with the one found in the different thymocyte subpopulations, the ADA/PNP ratio was very low and similar to the early thymocytes, whereas the LDH isoenzymes approached the pattern of the cortical thymocytes. This enzyme profile suggests that the enzyme content of the TNC is dependent on the presence of at least two different thymocyte subpopulations, the early thymocytes and the cortical thymocytes.

Adenosine Deaminase↗
PubMed1987

[Interaction of radiation-induced preleukemia cells and bone marrow grafts in C57BL/Ka mice].

The repopulation of thymus inoculated with radiation-induced preleukemia cells was studied in 400 R irradiated mice grafted with normal bone marrow cells. These marrow cells gave rise to an actively regenerating thymic progeny, as well as in 400 R treated mice receiving only a bone marrow graft. Moreover, the marrow graft did not prevent the progression of inoculated preleukemic cells towards lymphoma growth.

Animals↗
PubMed1987

[Relations between the capacity of thymic repeopling and the formation of lymphoma obtained by radiation-induced preleukemic cells in C57BL/Ka mice].

We have analyzed the repopulation of thymuses injected with preleukemic cells obtained at various interval after fractionated irradiation. Our results show that preleukemic cells can repopulate the thymus transiently as normal thymocytes or they can proliferate in recipients. In all cases, preleukemic cells can give rise to donor lymphomas.

Animals↗
PubMed1987

[Cytofluorimetric study of ploidy in the preleukemic thymus in C57BL/Ka mice under fractionated irradiation].

The ploidy of the thymus was studied in C57B1/Ka mice irradiated with 4 weekly X-Ray doses of 1.75 Gy. The determination of nuclear DNA content was performed by flow cytometry of intact thymocytes labeled with propidium iodide in presence of a mixture of chicken and rainbow trout red blood cells as internal reference standards. The method has been tested by detecting the sex difference in DNA content of G0/G1 of normal thymic mouse cells. The mean value was 2.9% higher in female mice. The thymus of almost 60% of irradiated male mice present a slight hypoploidy of 2.6% one month after the last irradiation.

Animals↗
PubMed1987

[Migration of bone marrow cells toward the thymus in C57BL/Ka under fractionated irradiation].

Fractionated whole body X-irradiation (4 X 1.75 Gy at weekly intervals) induces a high percentage of thymic lymphomas in C57BL/Ka mice. These tumors develop after a long latency period during which the thymic lymphopoiesis is deeply altered. In the present work, we test wether those modifications are due to lack of prothymocyte homing to preleukemic thymuses. Our results show that the preleukemic state of the thymus don't prevent the homing of normal marrow precursors grafted immediately after an irradiation of 4 Gy. Thus the alterations of thymic lymphopoiesis observed after a leukemogenic irradiation are not due to a modification in the thymus receptivity to thymocyte precursors.

Animals↗
PubMed1987

Plasmacytoma of the thyroid: a case report, a study with use of the immunoperoxidase technique, and a review of the literature.

A case of solitary plasmacytoma of the thyroid is reported. A monoclonal component (IgG lambda) was identified in the serum of the patient and disappeared after total thyroidectomy and radiotherapy. The use of the immunoperoxidase technique on thyroid, bone marrow, and lymph node specimens allowed us to demonstrate the production of IgG lambda by the tumor, and to rule out the possibility of multiple myeloma. Previously reported cases are reviewed (15 cases). The diagnostic criteria, the association with thyroiditis, and the treatment of this rare disorder are discussed.

Bone Marrow↗