• Molecules and Cells
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• 제38권6호
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• pp.548-561
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• 2015

By combining conventional single cell analysis with flow cytometry and public database searches with bioinformatics tools, we extended the expression profiling of thymic stromal cotransporter (TSCOT), Slc46A2/Ly110, that was shown to be expressed in bipotent precursor and cortical thymic epithelial cells. Genome scale analysis verified TSCOT expression in thymic tissue- and cell type- specific fashion and is also expressed in some other epithelial tissues including skin and lung. Coexpression profiling with genes, Foxn1 and Hoxa3, revealed the role of TSCOT during the organogenesis. TSCOT expression was detected in all thymic epithelial cells (TECs), but not in the $CD31^+$endothelial cell lineage in fetal thymus. In addition, ABC transporter-dependent side population and Sca-$1^+$ fetal TEC populations both contain TSCOT-expressing cells, indicating TEC stem cells express TSCOT. TSCOT expression was identified as early as in differentiating embryonic stem cells. TSCOT expression is not under the control of Foxn1 since TSCOT is present in the thymic rudiment of nude mice. By searching variations in the expression levels, TSCOT is positively associated with Grhl3 and Irf6. Cytokines such as IL1b, IL22 and IL24 are the potential regulators of the TSCOT expression. Surprisingly, we found TSCOT expression in the lung is diminished in lung cancers, suggesting TSCOT may be involved in the suppression of lung tumor development. Based on these results, a model for TEC differentiation from the stem cells was proposed in context of multiple epithelial organ formation.

• IMMUNE NETWORK
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• 제23권5호
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• pp.36.1-36.16
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• 2023

Thymic epithelial cells (TECs) play a critical role in thymic development and thymopoiesis. As individuals age, TECs undergo various changes that impact their functions, leading to a reduction in cell numbers and impaired thymic selection. These age-related alterations have been observed in both mice and humans. However, the precise mechanisms underlying age-related TEC dysfunction remain unclear. Furthermore, there is a lack of a comprehensive study that connects mouse and human biological processes in this area. To address this gap, we conducted an extensive transcriptome analysis of young and old TECs in mice, complemented by further analysis of publicly available human TEC single-cell RNA sequencing data. Our analysis revealed alterations in both known and unknown pathways that potentially contribute to age-related TEC dysfunction. Specifically, we observed downregulation of pathways related to cell proliferation, T cell development, metabolism, and cytokine signaling in old age TECs. Conversely, TGF-β, BMP, and Wnt signaling pathways were upregulated, which have been known to be associated with age-related TEC dysfunctions or newly discovered in this study. Importantly, we found that these age-related changes in mouse TECs were consistently present in human TECs as well. This cross-species validation further strengthens the significance of our findings. In conclusion, our comprehensive analysis provides valuable insight into the biological and immunological characteristics of aged TECs in both mice and humans. These findings contribute to a better understanding of thymic involution and age-induced immune dysfunction.

• 대한세포병리학회지
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• 제2권1호
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• pp.36-42
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• 1991

We report 4 cases of malignant thymoma which were composed of 2 cases of invasive thymoma and 2 cases of thymic carcinoma. The cytologic findings of invasive thymoma were similar to those of benign thymoma. The distinctive cytologic features of thymic carcinoma were necrotic background, irregular clusters and individually scattered arrangement of anaplastic epithelial cells, and some scattered mature small lymphocytes. These findings may be found in the Hodgkin's lymphoma, seminoma, and metastatic squamous ceil carcinoma, undifferentiated carcinoma, and large ceil carcinoma of the lung. But, the feature of irregular clustering of anaplastic epithelial cell haying scanty cytoplasm was different from Hodgkin's lymphoma and seminoma. Clinical and radiologic findings as well as cytologic finding were helpful in differential diagnosis of thymic carcinoma from metastatic carcinoma.

• 생명과학회지
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• 제33권8호
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• pp.612-622
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• 2023

생체 면역조직에서는 면역세포의 성장, 분화에 있어서 매우 중요한 역할을 수행하는 면역조직 기질세포가 존재하며, 이들은 서로 연결된 3차원적인 그물구조를 형성하면서 그 사이의 공간에 위치한 면역세포와의 상호작용을 통해 다양한 면역반응을 수행한다. 따라서 생체환경을 모사한 면역세포의 배양이 이루어지기 위해서는 면역세포들이 상호작용할 수 있는 3차원적 면역조직 기질세포 뼈대의 구축이 매우 중요한 의의를 지닌다. 특히 면역반응에서 핵심적인 기능을 수행하는 T세포의 생존, 성장 및 분화에 있어서 필수적인 역할을 하는 흉선상피세포에 대한 3차원적 배양은 T세포의 연구에 필수적으로 요구되지만, 아직 이에 관한 연구가 거의 이루어지지 않은 실정이다. 본 연구에서 흉선상피세포는 폴리도파민으로 코팅된 PCL 및 PCL/PLGA 지지체에서 비코팅군에 비해 부착 및 성장이 촉진되었다. 또한 폴리도파민으로 코팅된 지지체에서 흉선상피세포를 배양하였을 때 2차원 배양군에 비해 흉선세포형성촉진인자의 유전자 발현이 더 증가하였다. 따라서 본 연구는 면역조직 기질세포의 3차원 배양 기술의 개발에 크게 기여할 수 있을 것으로 사료된다.

• Journal of Yeungnam Medical Science
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• 제27권2호
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• pp.98-104
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• 2010

원발성 전 종격동 종양은 종격동 종양의 반이상을 차지하고 그 종류도 다양하다. 흉선 상피 종양이 가장 흔하고 악성 흉선종은 드물다. 생식세포종은 두 번째로 흔한 전 종격동 종양으로 보다 어린나이에 발생하며 대부분 양성이다. 임파종은 대부분 전신성 질환의 흉부 침습 형태로 나타나나 원발성 흉부 임파종은 Hodgkin씨 병이 많다. 저자는 대표적인 전종격동 종양의 임상증상과 영상의학적 소견을 소개한다.

• IMMUNE NETWORK
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• 제15권3호
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• pp.111-120
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• 2015

Dendritic cells (DCs) play a significant role in establishing self-tolerance through their ability to present self-antigens to developing T cells in the thymus. DCs are predominantly localized in the medullary region of thymus and present a broad range of self-antigens, which include tissue-restricted antigens expressed and transferred from medullary thymic epithelial cells, circulating antigens directly captured by thymic DCs through coticomedullary junction blood vessels, and peripheral tissue antigens captured and transported by peripheral tissue DCs homing to the thymus. When antigen-presenting DCs make a high affinity interaction with antigen-specific thymocytes, this interaction drives the interacting thymocytes to death, a process often referred to as negative selection, which fundamentally blocks the self-reactive thymocytes from differentiating into mature T cells. Alternatively, the interacting thymocytes differentiate into the regulatory T (Treg) cells, a distinct T cell subset with potent immune suppressive activities. The specific mechanisms by which thymic DCs differentiate Treg cells have been proposed by several laboratories. Here, we review the literatures that elucidate the contribution of thymic DCs to negative selection and Treg cell differentiation, and discusses its potential mechanisms and future directions.

• 대한두경부종양학회지
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• 제29권2호
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• pp.68-70
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• 2013

Thymoma is the most common anterior mediastinal mass in adult, and arises from thymic epithelial cells which includes consists various proportions of epithelial and lymphocytic aspect. Thymic epithelial cell arises from the ventral wings of the third and fourth branchial pouches in the embryo, and these cells are considered tumorous condition of thymoma. Surgical resection is main treatment of thymoma. And adjuvant chemotherapy or radiation is considered due to postoperative pathologic diagnosis. We experienced a tumor which located from left anterior neck along superior mediastinum on chest radiograph incidentally and diagnosed parathyroid adenoma clinically. After surgical removal, final pathologic report was thymoma. Here, we present the case with a review of the related literatures.

• IMMUNE NETWORK
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• 제4권2호
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• pp.81-87
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• 2004

Background: In the thymus, developing thymocytes continually interact with thymic epithelial cell components. Self MHC restriction of mature T cells are imposed in the thymus through interaction of immature double positive thymocytes and thymic cortical epithelial cells. The site of negative selection, however, is a matter of debate. Through systemic injection of anti-TCR antibody or antigenic peptides, investigators suggested that most of the negative selection occurs in the thymic cortex. But the requirements for negative selection, i.e cellular counterparts and costimulatory molecules are more available in the medulla or cortico-medullary junction rather than in the thymic cortex. Methods: The direct and indirect pathways of thymocyte death after systemic anti-TCR antibody injection were separated through several experimental systems. B6 mice were either adrenalectomized or sham-adrenalectomized to evaluate the role of endogenous glucocorticoids from adrenal gland. Role of TNF were evaluated through using TNF receptor double knockout mice. Results: We found that without indirectly acting mediators such as $TNF-\alpha$ or corticosteroid, double positive thymocyte death were minimal by systemic injection of anti-TCR antibody in TNF receptor double knockout neonatal mice. Also by analyzing neonatal wild-type mice with adoptively transferred mature T cells, only peripheral activation of mature T cells could induce extensive double positive thymocyte death. Conclusion: Thus, systemically injected anti-TCR antibody mediated thymocyte death are mostly induced through indirect pathway.

• Journal of Animal Science and Technology
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• 제57권10호
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• pp.30.1-30.4
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• 2015

The present study was aimed to study the light and electron microscopic studies of thymic Hassall's corpuscles was done in various age groups of Nandanam Chicken ranging from day-old to forty weeks. Hassall's corpuscles are special, unique structures present in thymic medulla and also in the cortex of all the age groups of Nandanam chicken (from hatch to forty weeks) in the present study. Size of the Hassall's corpuscles in the medulla is larger than the ones present in the cortical region of thymus. The Hassall's corpuscles are made up of structureless eosinophilic mass surrounded by concentrically arranged reticuloepithelial cells. Under electron microscope, the Hassall's corpuscles were composed of reticuloepithelial cells interconnected by many desmosomes. The epithelial cells had abundance of cytoplasmic fibrils and desmosomes with few mitochondria and ribosomes. The nucleus was oval or round which was slightly indented. The centre of the Hassall's corpuscles was appeared either solid or cystic. The cystic corpuscles had cell debris within the cyst lumen.

• 대한후두음성언어의학회지
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• 제26권2호
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• pp.133-136
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• 2015

Spindle epithelial tumor with thymus-like differentiation (SETTLE) is an extremely rare type of thyroid tumor, with spares reports on its clinical course. SETTLE is derived from branchial pouch or thymic remnants, and classified as a low grade, malignant neoplasm due to its indolent growth and tendency to develop delayed metastasis. Therefore, stringent initial workups and long-term follow-up are required to prevent misdiagnosis. We present a case of recurrent spindle epithelial tumor with thymus-like differentiation (SETTLE) in the glottis of 57 year-old male patient, who had a history of surgical excision for the SETTLE from the thyroid gland 5 years ago. Transoral CO2 laser surgery was performed to remove the glottic tumor and there was no evidence of local recurrence at 11 months postoperatively.