scispace - formally typeset
Search or ask a question
Author

Linh T. Nguyen

Bio: Linh T. Nguyen is an academic researcher from Ontario Institute for Cancer Research. The author has contributed to research in topics: Cytotoxic T cell & Medicine. The author has an hindex of 15, co-authored 22 publications receiving 3799 citations. Previous affiliations of Linh T. Nguyen include University Health Network & The Breast Cancer Research Foundation.

Papers
More filters
Journal ArticleDOI
18 Nov 1999-Nature
TL;DR: The results show that both systemic and local T-cell activation can lead to OPGL production and subsequent bone loss, and they provide a novel paradigm for T cells as regulators of bone physiology.
Abstract: Bone remodelling and bone loss are controlled by a balance between the tumour necrosis factor family molecule osteoprotegerin ligand (OPGL) and its decoy receptor osteoprotegerin (OPG)1,2,3. In addition, OPGL regulates lymph node organogenesis, lymphocyte development and interactions between T cells and dendritic cells in the immune system3,4,5. The OPGL receptor, RANK, is expressed on chondrocytes, osteoclast precursors and mature osteoclasts4,6. OPGL expression in T cells is induced by antigen receptor engagement7, which suggests that activated T cells may influence bone metabolism through OPGL and RANK. Here we report that activated T cells can directly trigger osteoclastogenesis through OPGL. Systemic activation of T cells in vivo leads to an OPGL-mediated increase in osteoclastogenesis and bone loss. In a T-cell-dependent model of rat adjuvant arthritis characterized by severe joint inflammation, bone and cartilage destruction and crippling, blocking of OPGL through osteoprotegerin treatment at the onset of disease prevents bone and cartilage destruction but not inflammation. These results show that both systemic and local T-cell activation can lead to OPGL production and subsequent bone loss, and they provide a novel paradigm for T cells as regulators of bone physiology.

1,843 citations

Journal ArticleDOI
12 Jan 2001-Cell
TL;DR: Bcl10 functions as a positive regulator of lymphocyte proliferation that specifically connects antigen receptor signaling in B and T cells to NF-kappaB activation.

548 citations

Journal ArticleDOI
TL;DR: It is shown that after a vaccine-induced immune response, adjuvant interleukin-7 (IL-7) improves antitumor responses and survival in an animal model, and the ability of adjUvant IL-7 to antagonize inhibitory networks at the cellular and molecular level has major implications for immunotherapy in the treatment of tumors.
Abstract: Identifying key factors that enhance immune responses is crucial for manipulating immunity to tumors. We show that after a vaccine-induced immune response, adjuvant interleukin-7 (IL-7) improves antitumor responses and survival in an animal model. The improved immune response is associated with increased IL-6 production and augmented T helper type 17 cell differentiation. Furthermore, IL-7 modulates the expression of two ubiquitin ligases: Casitas B-lineage lymphoma b (Cbl-b), a negative regulator of T cell activation, is repressed, and SMAD-specific E3 ubiquitin protein ligase-2 (Smurf2) is enhanced, which antagonizes transforming growth factor-beta signaling. Notably, we show that although short term IL-7 therapy potently enhances vaccine-mediated immunity, in the absence of vaccination it is inefficient in promoting antitumor immune responses, despite inducing homeostatic proliferation of T cells. The ability of adjuvant IL-7 to antagonize inhibitory networks at the cellular and molecular level has major implications for immunotherapy in the treatment of tumors.

215 citations

Journal ArticleDOI
TL;DR: Findings suggest that the induction of tolerance versus autoimmunity is determined by resting versus activated antigen-presenting cells.
Abstract: The mechanisms that determine whether receptor stimulation leads to lymphocyte tolerance versus activation remain poorly understood. We have used rat insulin promoter (RIP)-gp/P14 double-transgenic mice expressing the lymphocytic choriomeningitis virus (LCMV) glycoprotein (gp) on pancreatic β-islet cells together with T cells expressing an LCMV-gp–specific T cell receptor to assess the requirements for the induction of autoimmunity. Our studies have shown that administration of the gp peptide gp33 leads to the activation of P14-transgenic T cells, as measured by the upregulation of activation markers and the induction of effector cytotoxic activity. This treatment also leads to expansion and deletion of P14 T cells. Despite the induction of cytotoxic T lymphocyte activity, peptide administration is not sufficient to induce diabetes. However, the administration of gp peptide together with an activating anti-CD40 antibody rapidly induces diabetes. These findings suggest that the induction of tolerance versus autoimmunity is determined by resting versus activated antigen-presenting cells.

167 citations

Journal ArticleDOI
TL;DR: A model to investigate how the affinity of the T-cell receptor (TCR) for the activating agent influences autoimmunity shows that an approximately fivefold difference in the TCR affinity for the activates ligand results in a 50% reduction in the incidence of autoIMmunity.
Abstract: Autoimmune diseases are often mediated by self-reactive T cells, which must be activated to cause immunopathology. One mechanism, known as molecular mimicry, proposes that self-reactive T cells may be activated by pathogens expressing crossreactive ligands1,2,3. Here we have developed a model to investigate how the affinity of the T-cell receptor (TCR) for the activating agent influences autoimmunity. Our model shows that an approximately fivefold difference in the TCR affinity for the activating ligand results in a 50% reduction in the incidence of autoimmunity. A reduction in TCR-ligand affinity to approximately 20 times lower than normal does not induce autoimmunity despite the unexpected induction of cytotoxic T lymphocytes (CTLs) and insulitis. Furthermore, in the absence of a key negative regulatory molecule, Cbl-b4,5, 100% of mice develop autoimmunity upon infection with viruses encoding the lower-affinity ligand. Therefore, autoimmune disease is sensitive both to the affinity of the activating ligand and to normal mechanisms that negatively regulate the immune response.

159 citations


Cited by
More filters
Journal ArticleDOI
15 May 2003-Nature
TL;DR: Discovery of the RANK signalling pathway in the osteoclast has provided insight into the mechanisms of osteoporosis and activation of bone resorption, and how hormonal signals impact bone structure and mass.
Abstract: Osteoclasts are specialized cells derived from the monocyte/macrophage haematopoietic lineage that develop and adhere to bone matrix, then secrete acid and lytic enzymes that degrade it in a specialized, extracellular compartment. Discovery of the RANK signalling pathway in the osteoclast has provided insight into the mechanisms of osteoclastogenesis and activation of bone resorption, and how hormonal signals impact bone structure and mass. Further study of this pathway is providing the molecular basis for developing therapeutics to treat osteoporosis and other diseases of bone loss.

5,760 citations

Journal ArticleDOI
TL;DR: An overview of established NF-kappaB signaling pathways is provided with focus on the current state of research into the mechanisms that regulate IKK activation and NF- kappaB transcriptional activity.
Abstract: The transcription factor NF-kappaB has been the focus of intense investigation for nearly two decades. Over this period, considerable progress has been made in determining the function and regulation of NF-kappaB, although there are nuances in this important signaling pathway that still remain to be understood. The challenge now is to reconcile the regulatory complexity in this pathway with the complexity of responses in which NF-kappaB family members play important roles. In this review, we provide an overview of established NF-kappaB signaling pathways with focus on the current state of research into the mechanisms that regulate IKK activation and NF-kappaB transcriptional activity.

3,829 citations

Journal ArticleDOI
23 Feb 2001-Cell
TL;DR: The authors regret the inability to cite all of the primary literature contributing to this review due to length considerations, but wish to thank F. Chan, T. Migone, and J. Wang for insightful comments on the manuscript.

3,756 citations

Journal ArticleDOI
01 Sep 2000-Science
TL;DR: Osteopetrotic mutants have provided a wealth of information about the genes that regulate the differentiation of osteoclasts and their capacity to resorb bone.
Abstract: Osteoporosis, a disease endemic in Western society, typically reflects an imbalance in skeletal turnover so that bone resorption exceeds bone formation. Bone resorption is the unique function of the osteoclast, and anti-osteoporosis therapy to date has targeted this cell. The osteoclast is a specialized macrophage polykaryon whose differentiation is principally regulated by macrophage colony-stimulating factor, RANK ligand, and osteoprotegerin. Reflecting integrin-mediated signals, the osteoclast develops a specialized cytoskeleton that permits it to establish an isolated microenvironment between itself and bone, wherein matrix degradation occurs by a process involving proton transport. Osteopetrotic mutants have provided a wealth of information about the genes that regulate the differentiation of osteoclasts and their capacity to resorb bone.

3,604 citations

Journal ArticleDOI
TL;DR: The role of NF-κB proteins as potential therapeutic targets in clinical applications and their role in the immune system and inflammatory diseases are discussed.
Abstract: The nuclear factor-kappaB (NF-kappaB)/REL family of transcription factors has a central role in coordinating the expression of a wide variety of genes that control immune responses. There has been intense scientific activity in the NF-kappaB field owing to the involvement of these factors in the activation and regulation of key molecules that are associated with diseases ranging from inflammation to cancer. In this review, we focus on our current understanding of NF-kappaB regulation and its role in the immune system and inflammatory diseases. We also discuss the role of NF-kappaB proteins as potential therapeutic targets in clinical applications.

3,603 citations