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R V Rouse

Publications and source records attributed to R V Rouse.

At least 55 records · Page 3Linked to original sources

Traffic of mature lymphocytes into the mouse thymus.

The thymus is not generally considered to participate in bi-directional peripheral lymphocyte recirculation. We have demonstrated the entry of peripheral lymph node T cells using transfers between Thy-1 congenic mice. These peripheral T cells that enter the thymus bear an essentially medullary (or peripheral) phenotype and on section stains are confined to the medulla where they constitute 0.2-0.3% of the cells. These cells are remarkable for their frequent expression of the peripheral node homing receptor MEL-14 and for their persistence. Using transferred fluorescent labeled cells we also identify the entry of peripheral B cells into the thymus. Possible roles for peripheral B and T cells in the thymus include participation in thymocyte maturation or selection, the generation of thymic pathology and reactions to thymic pathologic processes.

Animals↗

Identification of subpopulations of mouse thymic epithelial cells in culture.

Mouse thymic stromal cells growing in vitro have been stained with fluorescent antibodies to identify the cells found in these cultures. By means of anti-cytokeratin antibody 35 beta H11, it could be shown that nearly all the cells in the cultures were epithelial. Three other antibodies which bind to specific regions of the thymus were used to detect subpopulations of the epithelial cells. Cells growing as confluent carpets stained with antibody ER-TR5, which is specific for medullary epithelium. Antigens for two other antibodies, MD2 (known to label cells at the medullary side of the cortical-medullary junction) and CDR1 (which reacts with cortical epithelium) were expressed on the cultured cells only after the addition of exogenous signals. MD2 antigen was expressed on a very small percentage of the cells incorporated into networks as well as a few dispersed cells, and seemed related to the activity of fibroblasts. CDR1 antigen appeared on the majority of the cells organized into networks and those dispersed in the cultures. Gamma-interferon (IFN-gamma) and IL-2, lymphokines usually associated with T-cell reactivity, were found to be involved in its expression. It was possible to isolate the CDR1 subpopulation from the cultures by means of the antigen present on the surface of these cells.

Animals↗

Rare peripheral T cells migrate to and persist in normal mouse thymus.

The traffic of T cells between the thymus and peripheral lymphoid organs is generally thought to be unidirectional. Using a technique of lymphocyte transfer between Thy-1 congenic mice, we demonstrate here the entry of rare peripheral lymph node T cells into the normal mouse thymus. At time points from 3 h to 24 wk after transfer, donor peripheral T cells were present in the host thymus, mainly as scattered single cells confined to the medulla. At 2 wk after transfer, donor T cells constituted 0.2% of the medullary thymocytes (compared with 11% of the peripheral lymph node T cells). As a population, these cells exhibited a stable mature immunophenotype (Ly-1hi, PNAlo, and mixed L3T4- and Lyt-2+). A minority of the donor T cells expressed high levels of the MEL-14 "homing receptor". The thymic medulla thus exhibits features of a peripheral lymphoid organ but differs in its low rate of turnover of recirculating T cells.

Antigens, Differentiation, T-Lymphocyte↗

Identification and surface phenotypic characterization of phosphorylcholine-specific idiotype-bearing T cells.

We have employed two-color staining with monoclonal anti-T-cell markers and a broadly reactive, nonbinding site monoclonal anti-idiotype to permit direct visualization of idiotype-bearing T cells in mouse lymph nodes following immunization with phosphorylcholine. Double positive cells peak in incidence on Days 8 to 12, as 17% of total idiotype+ cells but as only 0.7% of T cells. Such cells are antigen-specific, appearing in peripheral lymph nodes only following phosphorylcholine challenge. While Lyt-2+ and L3T4+ subsets are represented and both subsets reexpress the idiotypic determinant following its enzymatic removal, the L3T4+ subset represents the majority of idiotype+Thy-1+ cells. These findings raise the possibility that antigen-specific receptors on T and B cells, encoded by entirely different genetic information, may exhibit similarities in tertiary structure in portions of the molecules not directly involved in antigen binding. This is the first determination of the phenotype and chronology of appearance of idiotype-bearing normal T cells following immunization. It is consistent with previous reports of functionally defined idiotype-bearing T cells and provides direct support for the existence of such cells.

Animals↗

Independent developmental regulation of migratory granule neurons and their cerebellar ligand in the mouse.

Interactions between migratory granule neurons and the developing molecular layer of the mouse cerebellum were examined using an in situ binding assay. Single cell suspensions of postnatal granule neurons specifically adhere to unfixed frozen cerebellar tissue sections. We investigated the influence of postnatal age of granule neurons and of tissue on this interaction. Granule neurons from P10 (the time of peak migratory activity) bind preferentially to the molecular layer. Premigratory granule neurons, P5, do not bind age-matched cerebellar tissue. Postmigratory granule neurons, P14 and older, adhere to the molecular and internal granular layers of age-matched and older cerebellar tissue but not to younger tissue. These binding patterns are most simply explained as a single receptor-ligand system in which both elements exhibit independent developmental regulation. Although granule neurons lose the ability to bind with increasing age, the molecular layer ligand retains its capacity for this interaction into adulthood, long after normal migration has ceased.

Aging↗

Human thymomas: evidence of immunohistologically defined normal and abnormal microenvironmental differentiation.

Fifteen human thymomas were analyzed by immunoperoxidase studies on frozen and paraffin-embedded tissue sections in an attempt to identify the existence of immunologically defined microenvironments. All nine lymphocyte predominant thymomas contained a predominance of lymphocytes bearing the phenotype of cortical thymocytes and dendritic Class II major histocompatibility complex antigen-positive epithelial cells, thus defining cortical-like microenvironments. Medullary-like foci were also seen in all of these cases. Minor phenotypic abnormalities in Leu-2 and -3 antigen expression were seen in three cases. In contrast, the two epithelial predominant thymomas and four mixed thymomas all exhibited features of aberrant microenvironmental differentiation, with only two cases showing demarcation into cortical and medullary foci. A lack of Class II major histocompatibility complex antigens was associated with a decrease in the lymphoid populations and an increase in Leu-1 antigen expression by T cells of otherwise normal cortical phenotype when lymphocytes were present. In contrast, lack of Class I antigen on epithelial cells was not associated with any abnormality in lymphocyte phenotype or microenvironmental organization. We document for the first time abnormal microenvironments in thymomas that may offer insights into understanding normal thymic differentiation.

Antibodies, Monoclonal↗

The diagnostic utility of the keratin profiles of hepatocellular carcinoma and cholangiocarcinoma.

A total of 32 hepatocellular carcinomas (HCC), 10 cholangiocarcinomas (CC), one combined HCC-CC, and 10 adenocarcinomas metastatic to the liver were studied immunohistochemically using AE1 and Cam 5.2, monoclonal antikeratin antibodies with different specificities. AE1 recognizes keratins with molecular weights of 56.5, 50/50', 48, and 40 kd (keratin nos. 10, 14, 15, 16, and 19, according to Moll's catalog), and labels many epithelia, including bile duct epithelium, but not hepatocytes. Both biliary epithelium and hepatocytes are stained by Cam 5.2, which reacts with keratins of molecular weights 50, 43, and 39 kd (corresponding to keratin nos. 8, 18, and 19). Tissues were formalin fixed, paraffin embedded, and a three-stage immunoperoxidase technique was employed. Of 32 pure HCCs, 29 were unreactive with AE1 yet were positive with Cam 5.2. The intensity and extent of immunostaining with Cam 5.2 did not correlate with tumor grade. In contrast to the HCCs, all 10 CCs and the 10 hepatic metastases were strongly positive with both AE1 and Cam 5.2. The combined HCC-CC was also labeled by both antibodies. We conclude that most HCCs express an immunohistochemical keratin profile identical to that of nonneoplastic hepatocytes, which differs from the keratin patterns of bile ducts, CCs, and metastatic adenocarcinomas from a variety of primary sites. These differences in immunoreactivity with antikeratin antibodies may prove useful in diagnostic surgical pathology.

Adenoma, Bile Duct↗

Study of murine T cell migration using the Thy-1 allotypic marker. Demonstration of antigen-specific homing to lymph node germinal centers.

We describe the use of Thy-1 alloantigen as a marker for in vivo T lymphocyte homing studies. Following transfer of 5 x 10(7) peripheral node T cells i.v., 32% of the transferred cells could be recovered in the host lymphoid organs (spleen, lymph nodes, Peyer's patches, and thymus); 11% of the T cells in the lymph nodes were donor derived. The transferred T cells assume the same microenvironmental and immunophenotypic distribution as the host T cells. The transferred T cells are identifiable in peripheral lymph nodes up to 170 days posttransfer, gradually declining in number during this time without evidence of rejection. This Thy-1 transfer technique permits T lymphocyte homing studies to be performed under physiologic conditions without problems of loss of lymphocyte subsets, selective labeling of lymphocyte populations, or long-term marker loss or dilution. We then employ this technique to demonstrate the antigen-directed homing of peripheral T cells to lymph node germinal centers.

Animals↗

Monoclonal antibodies reactive with subsets of mouse and human thymic epithelial cells.

We describe monoclonal antibodies (MAB) reactive with subsets of mouse and human thymic epithelial cells. Rat MAb CDR1 reacts with mouse but not human cortical epithelial cells. Immunologic staining of thymic nurse cells in suspension indicates the CDR1 antigen is located on the cell surface. Mouse MAb CDR2 reacts with human but not mouse cortical thymic epithelial cells. Rat MAb MD1 and MD2 detect different determinants expressed by most medullary epithelial cells in mouse thymus but fewer such cells in human thymus. In addition, MD1 detects flattened subcapsular cells rarely in mouse thymus but frequently in human thymus. Two-color stains using an anti-keratin antiserum demonstrate the epithelial nature of the cells reactive with these antibodies. The antigens detected by CDR1 and MD1 first appear during the neonatal period, achieving adult distribution by postnatal days 14 and 4, respectively. The extra-thymic staining of these MAb is described. On the basis of their intra- and extra-thymic reactivities, these MAb differ from those previously reported and may permit dissection of the thymic microenvironment.

Aging↗

A panel approach to the evaluation of the sensitivity and specificity of antibodies for the diagnosis of routinely processed histologically undifferentiated human neoplasms.

The evaluation of antibodies for diagnostic purposes on routinely processed sections of histologically undiagnosable neoplasms presents special problems. The authors have addressed this problem by constructing a panel of putatively mutually exclusive antibodies and testing it on sections of anaplastic neoplasms. Tissue sections of 120 routinely processed histologically undifferentiated large cell human neoplasms with a histologic differential diagnosis of carcinoma versus lymphoma and/or melanoma were stained with a panel of antibodies composed of monoclonal antikeratin AE1, monoclonal antileukocyte common antigens PD7/26 and 2B11, and rabbit anti-S-100 protein. Only cases not diagnosable by routine morphologic examination were included. PD7/26 and/or 2B11 were positive in 61 cases (supporting lymphoma), AE1 was positive in 17 cases (supporting carcinoma), and anti-S-100 was positive in 25 cases (supporting melanoma). Seventeen neoplasms failed to react with any of the panel antibodies. None of the neoplasms reacted with antibodies directed against two or more different antigens. These results indicate excellent specificity (100%) and good sensitivity (86%) of the panel antibodies on histologically undifferentiated neoplasms. These results are significant on two levels: first, as a test of the panel approach to evaluate antibodies on anaplastic neoplasms, and, second, as a demonstration of the diagnostic utility of the specific panel the authors have employed in such cases.

Antibodies, Monoclonal↗

Expression of the Leu-8 antigen by B-cell lymphomas.

The Leu-8 antigen is found on the surface of many hematologic cells, including many T- and B-lymphocytes. With the use of a frozen-section immunoperoxidase technic, 152 B-cell non-Hodgkin's lymphomas were examined for Leu-8 expression. Of these lymphomas, 53% expressed Leu-8. Subclassification of the lymphomas with the use of the International Working Formulation showed that most small lymphocytic, intermediate lymphocytic, and diffuse large cell lymphomas and about half of diffuse small cleaved, diffuse mixed, and follicular lymphomas expressed Leu-8. In contrast, all 17 cases of small noncleaved cell (Burkitt's) lymphoma and 9 of 10 cases of multiple myeloma/plasmacytoma were Leu-8 negative. These results indicate that Leu-8 is expressed on a wide variety of B-cell lymphomas and that differences in Leu-8 expression may be useful in the diagnostic separation of small lymphocytic lymphoma with plasmacytoid features from multiple myeloma/plasmacytoma, and diffuse large cell lymphoma from Burkitt's lymphoma.

Antibodies, Monoclonal↗

Immunohistochemical staining in malignant mesotheliomas.

The immunoreactivity of five antibodies was evaluated on six routinely processed mesotheliomas to evaluate their ability to distinguish mesothelioma from metastatic adenocarcinoma. The diagnosis in all cases was confirmed by electron microscopic examination and histochemical stains for neutral mucin (periodic acid-Schiff-diastase) and acid mucin (alcian blue with and without hyaluronidase). AE1, a monoclonal antikeratin antibody that stains most carcinomas, reacted with all six cases of mesothelioma. HMFG-2 and anti-epithelial membrane antigen (antibodies reactive with human milk fat globule proteins), two other closely related antibodies reactive with most carcinomas, also reacted with all of the mesotheliomas in the authors' series. A polyclonal antibody to carcinoembryonic antigen (anti-CEA) did not stain any of the mesotheliomas in their series. Anti-Leu-M1 did not react with the mesotheliomas. The authors conclude that none of these antibodies, when used alone on routinely fixed paraffin-embedded material, is both sensitive and specific in the distinction of mesothelioma from adenocarcinoma. However, immunoperoxidase studies using anti-CEA and anti-Leu-M1 may occasionally be helpful when used in conjunction with other histochemical stains and electron microscopic examination in distinguishing mesothelioma from metastatic adenocarcinoma.

Antibodies, Monoclonal↗

Intrathymic presentation of circulating non-MHC antigens by medullary dendritic cells. An antigen-dependent microenvironment for T cell differentiation.

We present evidence for intrathymic presentation of soluble circulating antigens in vivo. Our results show that proteins of different molecular weight enter the mouse thymus rapidly after i.v. injection. The intrathymic presence of antigen was assayed by proliferation of cloned antigen-specific T helper cells, which were cocultured with purified thymic stromal cells; stromal cells were isolated and purified as lymphostromal cell complexes, which preexist in vivo. Antigen presentation copurified with non-adherent medullary dendritic cells (DC) (interdigitating cells). I-A- cortical macrophages forming thymocyte rosettes in vivo and I-A+ cortical epithelial cells forming thymic nurse cells (TNC) in vivo did not act as antigen presenting cells (APC) after antigen pulsing in vivo or in vitro. Thymic APC turn over physiologically and are rapidly replaced (within 2-5 wk) after lethal irradiation by donor bone marrow-derived cells. The frequency of thymocyte-DC interactions in vivo strictly correlates with thymic T cell differentiation, and is independent of the immune status of the animal. Fetal thymic APC seem to be secluded from antigen in the maternal circulation. Thymic DC-ROS probably represent the microenvironment where maturing T cells first encounter non-MHC antigens in the context of self-MHC antigens.

Animals↗

In situ identification of idiotype-positive cells participating in the immune response to phosphorylcholine.

The phosphorylcholine idiotype (Id)/anti-Id system has been used to study the role of antigen-specific cells in antigen-induced microenvironmental changes. Anti-Id staining of lymph nodes following PC immunization shows the presence of Id on follicular dendritic cells at 12 h and in plasma cells beginning at day 3. Germinal centers began to form at day 3, peaking in size and number at days 8-10. Scattered Id-positive small lymphocytes are present in germinal centers but with rare exceptions over 98% of germinal center cells are Id-negative. Idiotype-positive small lymphocytes are depleted from primary follicles adjacent to germinal centers but not from distant, unstimulated nodes. These results extend previous studies showing architectural alterations in lymph nodes following antigenic stimulation and demonstrate antigen-specific cells are a prominent component of these antigen-induced microenvironmental changes.

Animals↗

Composition of the lymphoid cell populations from omental milky spots during the immune response in C57BL/Ka mice.

The lymphoid cell composition of milky spots was analyzed in unprimed mice before and after i.p. immunization with sheep red blood cells. Milky spots contained surface immunoglobulin-positive B lymphocytes, and T cells of the helper and cytotoxic phenotype. After secondary antigen challenge the number of lymphocytes increased up to 40-fold, B and T cells were found to segregate into distinct areas in situ, and lymphocytes were found to associate with I-A-negative stromal cells in vivo. These findings qualify milky spots as a peripheral lymphoid organ exhibiting a remarkable change in number and composition of lymphocytes in response to a local antigen stimulus.

Animals↗

Localization of Thy-1 expression during postnatal development of the mouse cerebellar cortex.

Thy-1 is a cell membrane differentiation antigen with a restricted distribution in murine tissues. In both mice and rats the antigen is widely expressed in the CNS, while in the neonatal cerebellum it is expressed at very low levels. We have devised a protocol of immersion fixation by freeze-substitution that preserves both antigenicity and tissue morphology. We have stained freeze-substituted tissue sections of developing mouse cerebella with monoclonal anti-Thy-1. Thy-1 is faintly detectable at birth in Purkinje cells and in the molecular layer. The intensity in these two sites increases to a maximum at day 9; this subsequently decreases in the Purkinje cell cytoplasm until most are negative by day 21, but persists in the molecular layer into adulthood. Thy-1 is not detectable in the external granular layer and is only detectable in the glomeruli of the internal granular layer. Ascending fibre tracts are positive from day 5 onwards. The chronologic and anatomic expressions of Thy-1 are compatible with a role of Thy-1 in the generation and maintenance of synapses.

Aging↗

Is Ia antigen expression by thymic epithelial cells constitutive?

Thymic epithelial cells express class II MHC antigens (Ia) in the normal thymus. In a variety of special circumstances, generally associated with decreased or absent thymocyte populations, TEC fail to express Ia antigens. Although such observations might be interpreted based on the hypothesis that TEC Ia antigens have an effect on the differentiation of thymocytes, it is also possible that instead, the thymocytes have an effect on TEC Ia antigen expression.

Animals↗