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Dong-Ming Su

Bio: Dong-Ming Su is an academic researcher from University of North Texas Health Science Center. The author has contributed to research in topics: Thymic involution & Thymocyte. The author has an hindex of 25, co-authored 53 publications receiving 2342 citations. Previous affiliations of Dong-Ming Su include University of Texas at Tyler & University of Texas Health Science Center at Tyler.


Papers
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Journal ArticleDOI
TL;DR: Examination of the effects of chemopreventive agents on the surface expression of programmed death-1-ligand 1, a negative regulator of T cell anti-tumor immunity, reveals a potential link between chemotherapy and cancer immunoresistance.

242 citations

Journal ArticleDOI
TL;DR: It is shown that application of γ-secretase inhibitors to fetal thymus organ cultures interferes with T cell development in a manner consistent with loss or reduction of Notch1 function, and this system presents a system in which rapid evaluation of ιsecretase-targeted pharmaceuticals for their ability to inhibit Notch activity can be performed in a relevant context.
Abstract: A major therapeutic target in the search for a cure to the devastating Alzheimer9s disease is γ-secretase. This activity resides in a multiprotein enzyme complex responsible for the generation of Aβ42 peptides, precipitates of which are thought to cause the disease. γ-Secretase is also a critical component of the Notch signal transduction pathway; Notch signals regulate development and differentiation of adult self-renewing cells. This has led to the hypothesis that therapeutic inhibition of γ-secretase may interfere with Notch-related processes in adults, most alarmingly in hematopoiesis. Here, we show that application of γ-secretase inhibitors to fetal thymus organ cultures interferes with T cell development in a manner consistent with loss or reduction of Notch1 function. Progression from an immature CD4 − /CD8 − state to an intermediate CD4 + /CD8 + double-positive state was repressed. Furthermore, treatment beginning later at the double-positive stage specifically inhibited CD8 + single-positive maturation but did not affect CD4 + single-positive cells. These results demonstrate that pharmacological γ-secretase inhibition recapitulates Notch1 loss in a vertebrate tissue and present a system in which rapid evaluation of γ-secretase-targeted pharmaceuticals for their ability to inhibit Notch activity can be performed in a relevant context.

194 citations

Journal ArticleDOI
TL;DR: How T cell adaptive immunity mediates inflammaging and plays a crucial role in the progression of age-related neurological and cardiovascular diseases, as well as cancer is described.
Abstract: Immune system aging is characterized by the paradox of immunosenescence (insufficiency) and inflammaging (over-reaction), which incorporate two sides of the same coin, resulting in immune disorder. Immunosenescence refers to disruption in the structural architecture of immune organs and dysfunction in immune responses, resulting from both aged innate and adaptive immunity. Inflammaging, described as a chronic, sterile, systemic inflammatory condition associated with advanced age, is mainly attributed to somatic cellular senescence-associated secretory phenotype (SASP) and age-related autoimmune predisposition. However, the inability to reduce senescent somatic cells (SSCs), because of immunosenescence, exacerbates inflammaging. Age-related adaptive immune system deviations, particularly altered T cell function, are derived from age-related thymic atrophy or involution, a hallmark of thymic aging. Recently, there have been major developments in understanding how age-related thymic involution contributes to inflammaging and immunosenescence at the cellular and molecular levels, including genetic and epigenetic regulation, as well as developments of many potential rejuvenation strategies. Herein, we discuss the research progress uncovering how age-related thymic involution contributes to immunosenescence and inflammaging, as well as their intersection. We also describe how T cell adaptive immunity mediates inflammaging and plays a crucial role in the progression of age-related neurological and cardiovascular diseases, as well as cancer. We then briefly outline the underlying cellular and molecular mechanisms of age-related thymic involution, and finally summarize potential rejuvenation strategies to restore aged thymic function.

180 citations

Journal Article
TL;DR: Previous and most recent evidence is emphasized suggesting that early programming of the thymus, sexual dimorphism, and the efficiency of specific T-cell progenitors and theThymic microenvironment are all crucial determinants of immune activity from early life through advanced ages.
Abstract: Age-related thymic involution is characterized by a progressive regression in thymus size and a diminishment of thymic structure. A decrease in thymic compartments leads to the reduction of thymopoiesis. Thymic involution is closely associated with immunosenescence, a degeneration of the immune system primarily due to the alterations in T-cell composition. Strategies to improve the consequences of the aging thymus are currently under investigation. A wide array of knowledge has revealed a series of factors that are essential in the overall determination of thymic function and immune response. Evidence indicates that early programming of the thymus, sexual dimorphism, and the efficiency of specific T-cell progenitors and the thymic microenvironment are all crucial determinants of immune activity from early life through advanced ages. To fully understand the processes involved in age-related thymic involution, such determinants must be considered. The central purpose of this review is to emphasize previous and most recent evidence suggesting that these factors contribute to the influence of long-term immunity and ultimately shape the progression of thymic involution in advanced age.

170 citations

Journal ArticleDOI
TL;DR: In contrast to thymi in mice with the null allele, the Foxn1Δ/Δ thymus promoted T cell development, but with specific defects at both the double-negative and double-positive stages.
Abstract: Thymic epithelial cells (TECs) are required for T cell maturation within the thymus. In the nude (Foxn1(nu/nu)) mouse, TECs fail to differentiate. We have generated a hypomorphic allele called Foxn1(Delta), from which an N-terminal domain was deleted. The phenotype was thymus specific, identifying a tissue-specific activity for this domain. Foxn1(Delta/Delta) mice showed abnormal thymic architecture, lacking cortical and medullary domains. In contrast to thymi in mice with the null allele, the Foxn1(Delta/Delta) thymus promoted T cell development, but with specific defects at both the double-negative and double-positive stages. Thus, initiation and progression of TEC differentiation are genetically separable functions of Foxn1, and the N-terminal domain is required for crosstalk-dependent TEC differentiation.

154 citations


Cited by
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TL;DR: The authors showed that CD4+CD25+ cells contribute to maintaining self-tolerance by downregulating immune response to self and non-self Ags in an Ag-nonspecific manner, presumably at the T cell activation stage.
Abstract: Approximately 10% of peripheral CD4+ cells and less than 1% of CD8+ cells in normal unimmunized adult mice express the IL-2 receptor alpha-chain (CD25) molecules. When CD4+ cell suspensions prepared from BALB/c nu/+ mice lymph nodes and spleens were depleted of CD25+ cells by specific mAb and C, and then inoculated into BALB/c athymic nude (nu/nu) mice, all recipients spontaneously developed histologically and serologically evident autoimmune diseases (such as thyroiditis, gastritis, insulitis, sialoadenitis, adrenalitis, oophoritis, glomerulonephritis, and polyarthritis); some mice also developed graft-vs-host-like wasting disease. Reconstitution of CD4+CD25+ cells within a limited period after transfer of CD4+CD25- cells prevented these autoimmune developments in a dose-dependent fashion, whereas the reconstitution several days later, or inoculation of an equivalent dose of CD8+ cells, was far less efficient for the prevention. When nu/nu mice were transplanted with allogeneic skins or immunized with xenogeneic proteins at the time of CD25- cell inoculation, they showed significantly heightened immune responses to the skins or proteins, and reconstitution of CD4+CD25+ cells normalized the responses. Taken together, these results indicate that CD4+CD25+ cells contribute to maintaining self-tolerance by down-regulating immune response to self and non-self Ags in an Ag-nonspecific manner, presumably at the T cell activation stage; elimination/reduction of CD4+CD25+ cells relieves this general suppression, thereby not only enhancing immune responses to non-self Ags, but also eliciting autoimmune responses to certain self-Ags. Abnormality of this T cell-mediated mechanism of peripheral tolerance can be a possible cause of various autoimmune diseases.

5,929 citations

Journal ArticleDOI
TL;DR: Progression‐free survival was significantly longer with durvalumab than with placebo, and safety was similar between the groups, and the secondary end points also favored durvalsumab.
Abstract: BackgroundMost patients with locally advanced, unresectable, non–small-cell lung cancer (NSCLC) have disease progression despite definitive chemoradiotherapy (chemotherapy plus concurrent radiation therapy). This phase 3 study compared the anti–programmed death ligand 1 antibody durvalumab as consolidation therapy with placebo in patients with stage III NSCLC who did not have disease progression after two or more cycles of platinum-based chemoradiotherapy. MethodsWe randomly assigned patients, in a 2:1 ratio, to receive durvalumab (at a dose of 10 mg per kilogram of body weight intravenously) or placebo every 2 weeks for up to 12 months. The study drug was administered 1 to 42 days after the patients had received chemoradiotherapy. The coprimary end points were progression-free survival (as assessed by means of blinded independent central review) and overall survival (unplanned for the interim analysis). Secondary end points included 12-month and 18-month progression-free survival rates, the objective res...

2,958 citations

Journal Article
TL;DR: Coppe et al. as mentioned in this paper showed that human cells induced to senesce by genotoxic stress secrete myriad factors associated with inflammation and malignancy, including interleukin (IL)-6 and IL-8.
Abstract: PLoS BIOLOGY Senescence-Associated Secretory Phenotypes Reveal Cell-Nonautonomous Functions of Oncogenic RAS and the p53 Tumor Suppressor Jean-Philippe Coppe 1 , Christopher K. Patil 1[ , Francis Rodier 1,2[ , Yu Sun 3 , Denise P. Mun oz 1,2 , Joshua Goldstein 1¤ , Peter S. Nelson 3 , Pierre-Yves Desprez 1,4 , Judith Campisi 1,2* 1 Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America, 2 Buck Institute for Age Research, Novato, California, United States of America, 3 Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America, 4 California Pacific Medical Center Research Institute, San Francisco, California, United States of America Cellular senescence suppresses cancer by arresting cell proliferation, essentially permanently, in response to oncogenic stimuli, including genotoxic stress. We modified the use of antibody arrays to provide a quantitative assessment of factors secreted by senescent cells. We show that human cells induced to senesce by genotoxic stress secrete myriad factors associated with inflammation and malignancy. This senescence-associated secretory phenotype (SASP) developed slowly over several days and only after DNA damage of sufficient magnitude to induce senescence. Remarkably similar SASPs developed in normal fibroblasts, normal epithelial cells, and epithelial tumor cells after genotoxic stress in culture, and in epithelial tumor cells in vivo after treatment of prostate cancer patients with DNA- damaging chemotherapy. In cultured premalignant epithelial cells, SASPs induced an epithelial–mesenchyme transition and invasiveness, hallmarks of malignancy, by a paracrine mechanism that depended largely on the SASP factors interleukin (IL)-6 and IL-8. Strikingly, two manipulations markedly amplified, and accelerated development of, the SASPs: oncogenic RAS expression, which causes genotoxic stress and senescence in normal cells, and functional loss of the p53 tumor suppressor protein. Both loss of p53 and gain of oncogenic RAS also exacerbated the promalignant paracrine activities of the SASPs. Our findings define a central feature of genotoxic stress-induced senescence. Moreover, they suggest a cell-nonautonomous mechanism by which p53 can restrain, and oncogenic RAS can promote, the development of age-related cancer by altering the tissue microenvironment. Citation: Coppe JP, Patil CK, Rodier F, Sun Y, Mun oz DP, et al. (2008) Senescence-associated secretory phenotypes reveal cell-nonautonomous functions of oncogenic RAS and the p53 tumor suppressor. PLoS Biol 6(12): e301. doi:10.1371/journal.pbio.0060301 Introduction Cancer is a multistep disease in which cells acquire increasingly malignant phenotypes. These phenotypes are acquired in part by somatic mutations, which derange normal controls over cell proliferation (growth), survival, invasion, and other processes important for malignant tumorigenesis [1]. In addition, there is increasing evidence that the tissue microenvironment is an important determinant of whether and how malignancies develop [2,3]. Normal tissue environ- ments tend to suppress malignant phenotypes, whereas abnormal tissue environments such at those caused by inflammation can promote cancer progression. Cancer development is restrained by a variety of tumor suppressor genes. Some of these genes permanently arrest the growth of cells at risk for neoplastic transformation, a process termed cellular senescence [4–6]. Two tumor suppressor pathways, controlled by the p53 and p16INK4a/pRB proteins, regulate senescence responses. Both pathways integrate multiple aspects of cellular physiology and direct cell fate towards survival, death, proliferation, or growth arrest, depending on the context [7,8]. Several lines of evidence indicate that cellular senescence is a potent tumor-suppressive mechanism [4,9,10]. Many poten- tially oncogenic stimuli (e.g., dysfunctional telomeres, DNA PLoS Biology | www.plosbiology.org damage, and certain oncogenes) induce senescence [6,11]. Moreover, mutations that dampen the p53 or p16INK4a/pRB pathways confer resistance to senescence and greatly increase cancer risk [12,13]. Most cancers harbor mutations in one or both of these pathways [14,15]. Lastly, in mice and humans, a senescence response to strong mitogenic signals, such as those delivered by certain oncogenes, prevents premalignant lesions from progressing to malignant cancers [16–19]. Academic Editor: Julian Downward, Cancer Research UK, United Kingdom Received June 27, 2008; Accepted October 22, 2008; Published December 2, 2008 Copyright: O 2008 Coppe et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Abbreviations: CM, conditioned medium; DDR, DNA damage response; ELISA, enzyme-linked immunosorbent assay; EMT, epithelial–mesenchymal transition; GSE, genetic suppressor element; IL, interleukin; MIT, mitoxantrone; PRE, presenescent; PrEC, normal human prostate epithelial cell; REP, replicative exhaustion; SASP, senescence-associated secretory phenotype; SEN, senescent; shRNA, short hairpin RNA; XRA, X-irradiation * To whom correspondence should be addressed. E-mail: jcampisi@lbl.gov [ These authors contributed equally to this work. ¤ Current address: Genomics Institute of the Novartis Research Foundation, San Diego, California, United States of America December 2008 | Volume 6 | Issue 12 | e301

2,150 citations

Journal ArticleDOI
24 Dec 2004-Science

1,949 citations