Lymphocyte proliferation in immune-mediated diseases

• Published in: Trends in immunology Vol. 30; no. 9; pp. 430 - 438
• Main Authors: Datta, Shrimati, Sarvetnick, Nora
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.09.2009; Elsevier Limited
• Subjects: Allergy and Immunology; Animals; Antigens; Autoimmune diseases; Autoimmunity; Cell Proliferation; Cytokines - immunology; Homeostasis; Humans; Immune System Diseases - immunology; Immune System Diseases - pathology; Immunologic Surveillance; Infections; Lymphocytes; T cell receptors; T-Lymphocytes - immunology; T-Lymphocytes - metabolism; T-Lymphocytes - pathology; T-Lymphocytes, Regulatory - immunology; T-Lymphocytes, Regulatory - metabolism; T-Lymphocytes, Regulatory - pathology
• ISSN: 1471-4906; 1471-4981
• DOI: 10.1016/j.it.2009.06.002

Defects in T cell homeostatic mechanisms can result in T cell lymphopenia, defined as decreased numbers of lymphocytes. Lymphopenia results in homeostatic proliferation in order to maintain T cell homeostasis. It has been proposed that homeostatic proliferation can expand the pool of autoreactive T cells that promote autoimmunity, and indeed recent studies have further substantiated this observation in both animal models and humans. Conversely, homeostatic proliferation can promote tumor immunity by allowing tumor-specific T cells to accumulate. In this review, we discuss how the outcome of homeostatic proliferation can function both in a deleterious manner in autoimmunity and a beneficial way in tumor immunity. We also discuss the roles of various cytokines and T regulatory cells that control homeostatic proliferation.