scholarly journals Thymic Medulla Epithelial Cells Acquire Specific Markers by Post-Mitotic Maturation

1996 ◽  
Vol 5 (1) ◽  
pp. 25-36 ◽  
Author(s):  
Claude Penit ◽  
Bruno Lucas ◽  
Florence Vasseur ◽  
Theresa Rieker ◽  
Richard L. Boyd
Keyword(s):  
Epithelial Cells ◽  
Marrow Cell ◽  
Lymphoid Cells ◽  
Color Flow ◽  
Normal Bone Marrow Cell ◽  
Undifferentiated Cells ◽  
Single Positive ◽  
Thymic Medulla ◽  
Kinetics Of ◽  
Medullary Cells

The development of thymocyte subsets and of the thymic epithelium in SCID and RAG-2-/– mice was monitored after normal bone-marrow-cell transfer. The kinetics of thymic reconstitution and their relationships with cell proliferation were investigated by using bromodeoxyuridine to detect DNA-synthesizing cells among lymphoid cells by 3-color flow cytometry, and in epithelial compartments by staining frozen sections. Thymocytes started to express CD8 and CD4 10 days after transfer, simultaneously with extensive proliferation. The first mature CD4+single-positive cells were generated, from resting CD4+CD8+cells after day 15. During this day 10–15 period, many epithelial cells positive for cortexspecific or panepithelial markers were labeled with BrdUrd after pulse-injection. Organized medullary epithelium also developed after day,15, that is, synchronously with the appearance of mature thymocytes, but medullary cells were never found BrdUrd+. These results suggest that, in these models, the reconstitution of the thymic epithelial network proceeds through expansion of preexisting cortical or undifferentiated cells and by later maturation (acquisition of specific markers) of medullary cells. This last process is dependent of the presence of mature thymocytes.

D3: A Gene Induced During Myeloid Cell Differentiation of Linlo c-Kit+ Sca-1+ Progenitor Cells

Blood ◽  
1999 ◽  
Vol 93 (2) ◽  
pp. 527-536 ◽  
Author(s):  
Sarah R. Weiler ◽  
John M. Gooya ◽  
Mariaestela Ortiz ◽  
Schickwann Tsai ◽  
Steven J. Collins ◽  
...  
Keyword(s):  
Cell Differentiation ◽  
Progenitor Cells ◽  
Cell Lines ◽  
Marrow Cell ◽  
Physiological Role ◽  
Myeloid Cell ◽  
Lymphoid Cells ◽  
Rna Expression ◽  
Normal Bone Marrow Cell

In an effort to characterize molecular events contributing to lineage commitment and terminal differentiation of stem/progenitor cells, we have used differential display reverse transcription polymerase chain reaction (DDRT-PCR) and cell lines blocked at two distinct stages of differentiation. The cell lines used were EML, which is representative of normal multipotential primitive progenitors (Sca-1+, CD34+, c-Kit+, Thy-1+) able to differentiate into erythroid, myeloid, and B-lymphoid cells in vitro, and MPRO, which is a more committed progenitor cell line, with characteristics of promyelocytes able to differentiate into granulocytes. One clone isolated by this approach was expressed in MPRO but not in EML cells and contained sequence identical to the 3′ untranslated region of D3, a gene cloned from activated peritoneal macrophages of unknown function. We have observed a novel pattern of D3 gene expression and found that D3 is induced in EML cells under conditions that promote myeloid cell differentiation (interleukin-3 [IL-3], stem cell factor [SCF], and all-trans-retinoic acid [atRA]) starting at 2 days, corresponding to the appearance of promyelocytes. D3 RNA expression reached a maximum after 5 days, corresponding to the appearance of neutrophilic granulocytes and macrophages, and decreased by day 6 with increased numbers of differentiated neutrophils and macrophages in vitro. Induction of D3 RNA in EML was dependent on IL-3 and was not induced in response to SCF or atRA alone or SCF in combination with 15 other hematopoietic growth factors (HGF) tested. Similarly, D3 was not expressed in the normal bone marrow cell (BMC) counterpart of EML cells, Linlo c-Kit+Sca-1+ progenitor cells. D3 RNA expression was induced in these cells when cultured for 7 days in IL-3 plus SCF. A comparison of the expression of D3 RNA in cell lines and normal BMC populations demonstrated that D3 is induced during macrophage and granulocyte differentiation and suggests a potential physiological role for D3 in normal myeloid differentiation.

D3: A Gene Induced During Myeloid Cell Differentiation of Linlo c-Kit+ Sca-1+ Progenitor Cells

Blood ◽  
1999 ◽  
Vol 93 (2) ◽  
pp. 527-536 ◽  
Author(s):  
Sarah R. Weiler ◽  
John M. Gooya ◽  
Mariaestela Ortiz ◽  
Schickwann Tsai ◽  
Steven J. Collins ◽  
...  
Keyword(s):  
Cell Differentiation ◽  
Progenitor Cells ◽  
Cell Lines ◽  
Marrow Cell ◽  
Physiological Role ◽  
Myeloid Cell ◽  
Lymphoid Cells ◽  
Rna Expression ◽  
Normal Bone Marrow Cell

Abstract In an effort to characterize molecular events contributing to lineage commitment and terminal differentiation of stem/progenitor cells, we have used differential display reverse transcription polymerase chain reaction (DDRT-PCR) and cell lines blocked at two distinct stages of differentiation. The cell lines used were EML, which is representative of normal multipotential primitive progenitors (Sca-1+, CD34+, c-Kit+, Thy-1+) able to differentiate into erythroid, myeloid, and B-lymphoid cells in vitro, and MPRO, which is a more committed progenitor cell line, with characteristics of promyelocytes able to differentiate into granulocytes. One clone isolated by this approach was expressed in MPRO but not in EML cells and contained sequence identical to the 3′ untranslated region of D3, a gene cloned from activated peritoneal macrophages of unknown function. We have observed a novel pattern of D3 gene expression and found that D3 is induced in EML cells under conditions that promote myeloid cell differentiation (interleukin-3 [IL-3], stem cell factor [SCF], and all-trans-retinoic acid [atRA]) starting at 2 days, corresponding to the appearance of promyelocytes. D3 RNA expression reached a maximum after 5 days, corresponding to the appearance of neutrophilic granulocytes and macrophages, and decreased by day 6 with increased numbers of differentiated neutrophils and macrophages in vitro. Induction of D3 RNA in EML was dependent on IL-3 and was not induced in response to SCF or atRA alone or SCF in combination with 15 other hematopoietic growth factors (HGF) tested. Similarly, D3 was not expressed in the normal bone marrow cell (BMC) counterpart of EML cells, Linlo c-Kit+Sca-1+ progenitor cells. D3 RNA expression was induced in these cells when cultured for 7 days in IL-3 plus SCF. A comparison of the expression of D3 RNA in cell lines and normal BMC populations demonstrated that D3 is induced during macrophage and granulocyte differentiation and suggests a potential physiological role for D3 in normal myeloid differentiation.

scholarly journals Histological and cytological studies on the developing thymus of sharpsnout seabream, Diplodus puntazzo

1999 ◽  
Vol 194 (1) ◽  
pp. 39-50
Author(s):  
NICLA ROMANO ◽  
MONICA FANELLI ◽  
GIOVANNI MARIA DEL PAPA ◽  
GIUSEPPE SCAPIGLIATI ◽  
LUCIA MASTROLIA
Keyword(s):  
Epithelial Cells ◽  
Lymphoid Cells ◽  
Cortical Region ◽  
Marine Teleost ◽  
Diplodus Puntazzo ◽  
Transmission Electron ◽  
Undifferentiated Cells ◽  
Sharpsnout Seabream ◽  
Reticular Cells ◽  
D 20

The structure of the developing thymus of the marine teleost, Diplodus puntazzo, was studied by light and transmission electron microscopy. The first anlage of the thymus developed by d 20 postfertilisation (p.f.) as a group of undifferentiated cells dorsal to the epithelium of the branchial chamber. The organ increased significantly in size around d 51–66 p.f. and differentiation of cortex and medulla occurred concomitantly. On the basis of their localisation, 4 main types of epithelial cell were distinguished: (1) limiting, adjacent to the connective capsule; (2) medullary and cortical reticular cells; (3) nurse cells, located in the corticomedullary boundary; (4) Hassall-like corpuscles. The majority of medium to large blast-like lymphoid cells were localised in the medulla, while small lymphocytes were housed in the cortical region. These morphological features were maintained at later stages. However, in juveniles in the medulla we observed reticular epithelial cells with cysts and rare Hassall-like corpuscles. The study was designed to obtain more information concerning the histology of the developing thymus of sharpsnout seabream and give a concise description of the differentiation of epithelial cells and lymphoid cells in the thymic parenchyma.

scholarly journals Kinetics of Thymocyte Subset Development and Selection Revealed by Cyclosporin A Treatment

1995 ◽  
Vol 4 (2) ◽  
pp. 117-126 ◽  
Author(s):  
Russell D.J. Huby ◽  
Ray Hicks ◽  
Lindsey K. Goff
Keyword(s):  
Flow Cytometry ◽  
Cyclosporin A ◽  
Positive Selection ◽  
Maximal Effect ◽  
Color Flow ◽  
Progressive Development ◽  
Single Positive ◽  
Autoreactive Cells ◽  
Kinetics Of ◽  
Immature Thymocytes

Cyclosporin A (CsA) inhibits the development of mature thymocytes from their CD4+CD8+precursors, but may allow autoreactive cells to mature. Using 3-color flow cytometry, we have followed the progressive development of thymocytes, including potentially autoreactive cells, during CsA treatment. Numbers of CD4+CD8+CD3highthymocytes dropped immediately, suggesting that the generation of these mature thymocyte precursors, normally dependent upon positive selection, was inhibited by CsA. Numbers of CD4-CD8+thymocytes also declined rapidly, but CD4-CD8+thymocytes were unaffected lfor 2 days, suggesting that the mature single-positive subsets are not symmetrically derived from a common GsA-sensitive precursor. An exceptional subset of CD8 SP thymocytes, expressing CD45RA, did not respond to CsA for about 10 days, indicating that they are distantly derived from a CsA-sensitive precursor. Apoptosis of TCR-Vβ3+thymocytes caused byMtυ-6, quantified according to the down-regulation of CD4 and CD8 on immature thymocytes, was partially inhibited by CsA, to maximal effect within 24 hours. This did not, however, facilitate their development into mature thymocytes.

Platelet Microtubule Subunit Proteins

1979 ◽  
Vol 42 (05) ◽  
pp. 1630-1633 ◽  
Author(s):  
A G Castle ◽  
N Crawford
Keyword(s):  
Epithelial Cells ◽  
Gel Electrophoresis ◽  
Blood Platelets ◽  
Polyacrylamide Gel Electrophoresis ◽  
Polyacrylamide Gel ◽  
Lens Epithelial Cells ◽  
Molecular Weights ◽  
Kinetics Of ◽  
Microtubular Structures

SummaryBlood platelets contain microtubule proteins (tubulin and HMWs) which can be polymerised “in vitro” to form structures which resemble the microtubules seen in the intact platelet. Platelet tubulin is composed of two non-identical subunits a and p tubulin which have molecular weights around 55,000 but can be resolved in alkaline SDS-polyacrylamide gel electrophoresis. These subunits associate as dimers with sedimentation coefficients of about 5.7 S although it is not known whether the dimer protein is a homo- or hetero-dimer. The dimer tubulin binds the anti-mitotic drug colchicine and the kinetics of this binding are similar to those reported for neurotubulins. Platelet microtubules also contain two HMW proteins which appear to be essential and integral components of the fully assembled microtubule. These proteins have molecular weights greater than 200,000 daltons. Fluorescent labelled antibodies to platelet and brain tubulins stain long filamentous microtubular structures in bovine lens epithelial cells and this pattern of staining is prevented by exposing the cells to conditions known to cause depolymerisation of cell microtubules.

scholarly journals Selective involution of thymic medulla by cyclosporine A with a decrease of mature thymic epithelia, XCR1+ dendritic cells, and epithelium-free areas containing Foxp3+ thymic regulatory T cells

2021 ◽  
Author(s):  
Yasushi Sawanobori ◽  
Yusuke Kitazawa ◽  
Hisashi Ueta ◽  
Kenjiro Matsuno ◽  
Nobuko Tokuda
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
Cyclosporine A ◽  
Immunosuppressive Drugs ◽  
Cell System ◽  
Thymic Epithelial Cells ◽  
Complex Molecules ◽  
Single Positive ◽  
Thymic Medulla ◽  
Medullary Thymic Epithelial Cells

AbstractImmunosuppressive drugs such as cyclosporine A (CSA) can disrupt thymic structure and functions, ultimately inducing syngeneic/autologous graft-versus-host disease together with involuted medullas. To elucidate the effects of CSA on the thymus more precisely, we analyzed the effects of CSA on the thymus and T cell system using rats. In addition to confirming the phenomena already reported, we newly found that the proportion of recent thymic emigrants also greatly decreased, suggesting impaired supply. Immunohistologically, the medullary thymic epithelial cells (mTECs) presented with a relative decrease in the subset with a competent phenotype and downregulation of class II major histocompatibility complex molecules. In control rats, thymic dendritic cells (DCs) comprised two subsets, XCR1+SIRP1α−CD4− and XCR1−SIRP1α+CD4+. The former had a tendency to selectively localize in the previously-reported epithelium-containing areas of the rat medullas, and the number was significantly reduced by CSA treatment. The epithelium-free areas, another unique domains in the rat medullas, contained significantly more Foxp3+ thymic Tregs. With CSA treatment, the epithelium-free areas presented strong involution, and the number and distribution of Tregs in the medulla were greatly reduced. These results suggest that CSA inhibits the production of single-positive thymocytes, including Tregs, and disturbs the microenvironment of the thymic medulla, with a decrease of the competent mTECs and disorganization of epithelium-free areas and DC subsets, leading to a generation of autoreactive T cells with selective medullary involution.

scholarly journals Epithelial transglutaminase 2 is needed for T cell interleukin-17 production and subsequent pulmonary inflammation and fibrosis in bleomycin-treated mice

2011 ◽  
Vol 208 (8) ◽  
pp. 1707-1719 ◽  
Author(s):  
Keunhee Oh ◽  
Hyung-Bae Park ◽  
Ok-Jin Byoun ◽  
Dong-Myung Shin ◽  
Eui Man Jeong ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Epithelial Cells ◽  
Transforming Growth Factor ◽  
Inflammatory Responses ◽  
Tissue Injury ◽  
Marrow Cell ◽  
Transglutaminase 2 ◽  
Cell Phenotype ◽  
Interleukin 17 ◽  
Dependent Manner

Pulmonary fibrosis is a potentially life-threatening disease that may be caused by overt or asymptomatic inflammatory responses. However, the precise mechanisms by which tissue injury is translated into inflammation and consequent fibrosis remain to be established. Here, we show that in a lung injury model, bleomycin induced the secretion of IL-6 by epithelial cells in a transglutaminase 2 (TG2)–dependent manner. This response represents a key step in the differentiation of IL-17–producing T cells and subsequent inflammatory amplification in the lung. The essential role of epithelial cells, but not inflammatory cells, TG2 was confirmed in bone marrow chimeras; chimeras made in TG2-deficient recipients showed reduced inflammation and fibrosis, compared with those in wild-type mice, regardless of the bone marrow cell phenotype. Epithelial TG2 thus appears to be a critical inducer of inflammation after noninfectious pulmonary injury. We further demonstrated that fibroblast-derived TG2, acting downstream of transforming growth factor-β, is also important in the effector phase of fibrogenesis. Therefore, TG2 represents an interesting potential target for therapeutic intervention.

scholarly journals Cells expressing PAX8 are the main source of homeostatic regeneration of adult mouse endometrial epithelium and give rise to serous endometrial carcinoma

2020 ◽  
Vol 13 (10) ◽  
pp. dmm047035
Author(s):  
Dah-Jiun Fu ◽  
Andrea J. De Micheli ◽  
Mallikarjun Bidarimath ◽  
Lora H. Ellenson ◽  
Benjamin D. Cosgrove ◽  
...  
Keyword(s):  
Stem Cells ◽  
Epithelial Cells ◽  
Endometrial Carcinoma ◽  
Marrow Cell ◽  
Cell Types ◽  
Lineage Tracing ◽  
Cell Of Origin ◽  
Mouse Uterus ◽  
Endometrial Epithelium

ABSTRACTHumans and mice have cyclical regeneration of the endometrial epithelium. It is expected that such regeneration is ensured by tissue stem cells, but their location and hierarchy remain debatable. A number of recent studies have suggested the presence of stem cells in the mouse endometrial epithelium. At the same time, it has been reported that this tissue can be regenerated by stem cells of stromal/mesenchymal or bone marrow cell origin. Here, we describe a single-cell transcriptomic atlas of the main cell types of the mouse uterus and epithelial subset transcriptome and evaluate the contribution of epithelial cells expressing the transcription factor PAX8 to the homeostatic regeneration and malignant transformation of adult endometrial epithelium. According to lineage tracing, PAX8+ epithelial cells are responsible for long-term maintenance of both luminal and glandular epithelium. Furthermore, multicolor tracing shows that individual glands and contiguous areas of luminal epithelium are formed by clonal cell expansion. Inactivation of the tumor suppressor genes Trp53 and Rb1 in PAX8+ cells, but not in FOXJ1+ cells, leads to the formation of neoplasms with features of serous endometrial carcinoma, one of the most aggressive types of human endometrial malignancies. Taken together, our results show that the progeny of single PAX8+ cells represents the main source of regeneration of the adult endometrial epithelium. They also provide direct experimental genetic evidence for the key roles of the P53 and RB pathways in the pathogenesis of serous endometrial carcinoma and suggest that PAX8+ cells represent the cell of origin of this neoplasm.

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