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R G Scollay

Publications and source records attributed to R G Scollay.

11 recordsLinked to original sources
PubMed1982

Dihydrotestosterone and estradiol deplete corticosensitive thymocytes lacking in receptors for these hormones.

The sex steroids dihydrotestosterone (DHT) and estradiol (E2), were found to deplete the same cortical population of thymocytes as the glucocorticoid dexamethasone (DM) in intact and in adrenalectomized, castrated mice. Although receptors for DM were demonstrated in this cortical population, none were found for E2 or DHT. We suggest that the sex steroids bind to other thymic elements, possibly thymic reticular epithelial cells, which may in turn act secondarily on cortical thymocytes, or their precursors within the thymus.

Animals↗
PubMed1980

Thymus cell migration. Quantitative aspects of cellular traffic from the thymus to the periphery in mice.

We have used intrathymic injection of fluorescein isothiocyanate to label thymocytes in situ. The method gives random labeling of the thymocyte population and so can be used to quantitate the extent of migration of cells from the thymus to the periphery. Migrant cells can be visualized in frozen sections or cell suspensions of peripheral organs by their fluorescence. Our data show that in young adults, about 1% of thymocytes leave the thymus per day. Since the bulk of thymocytes turn over every 5 to 7 days, this indicates that the vast majority (95%) of thymocytes die within the thymus. Cells that do leave the thymus, go mainly to the T areas of lymph nodes, spleen and Peyer's patches. Migrants are extremely rare in bone marrow, gut and liver. Migration is about the same in neonates as in adults relative to the size of the thymus, but is considerably lower in older animals where it is only about 0.1% of thymocytes per day at the age of six months.

Aging↗
PubMed1980

Organ specificity of lymphocyte migration: mediation by highly selective lymphocyte interaction with organ-specific determinants on high endothelial venules.

Evidence is presented that the organ specificity of lymphocyte migration is determined by selective interaction of lymphocytes with specialized endothelial cells. Mouse Peyer's patch and lymph node lymphocytes bind preferentially to high endothelial venules (HEV) in frozen sections of Peyer's patches and peripheral nodes, respectively, and this in vitro binding preference accurately predicts their differential segregation in vivo 30 min after i.v. injection. Both in vivo and in vitro, about 1.4 times as many as many Peyer's patch as lymph node lymphocytes bind HEV in Peyer's patches, and, conversely, twice as many lymph node cells interact with HEV in nonmesenteric lymph nodes. Even greater specificity is shown by certain homogeneous lymphocyte populations, i.e. thymic lymphomas. Some lymphomas bind with remarkable selectivity to HEV in Peyer's patches, and others interact almost exclusively with those in lymph nodes indicating that the mechanisms mediating selective recognition of HEV are capable of nearly absolute discrimination. Mesenteric node HEV are unique in that they allow both Peyer's patch- and lymph node-specific cells to bind. It is proposed that lymphocyte surface receptors specific for organ-restricted endothelial cell determinants mediate the antigen-independent organ specificity of lymphocyte migration. According to this model, there are at least 2 sets of complementary lymphocyte and endothelial cell receptors, one mediating lymphocyte-HEV adherence in Peyer's patches, the other in lymph nodes.

Animals↗
PubMed1980

Direct fluorescent labeling of cells with fluorescein or rhodamine isothiocyanate. II. Potential application to studies of lymphocyte migration and maturation.

The effect of direct cell labeling with fluorescein or tetramethyl rhodamine isothiocyanate on lymphocyte migration is examined. In vitro conditions of labeling are defined which (1) do not significantly affect immediate or long term viability of lymphocytes (up to 2 weeks after transfer in vivo), (2) do not alter normal lymphocyte migration, (3) do not affect expression or detectability of surface antigens, and (4) permit direct visualization and counter-staining with fluorescent antibody reagents for days after intravenous injection. The potential application of this method to studies of lymphocyte migration and maturation is discussed.

Animals↗
PubMed1975

Studies on FeSV induced sarcomata in sheep with particular reference to the regional lymphatic system.

Inocula of cultured sheep cells that had been transformed with FeSV were injected into the legs of sheep so that the changes in the cellular and humoral composition of the efferent lymph from the regional node could be studied throughout the immune responses. The times at which immunoblasts and specific antibodies appeared in the lymph were similar to those recorded during responses to conventional antigens. The antiboides were mainly 7S, G1 immunoglobulins directed against virion antigens on the membranes of the transformed cells.

Animals↗