¹Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA

Correspondence: You Wen HE, Tel: 1-919-613-7870; Fax: 1-919-684-8982 E-mail: he000004@mc.duke.edu

Abstract

Apoptosis plays an essential role in T cell biology. Thymocytes expressing nonfunctional or autoreactive TCRs are eliminated by apoptosis during development. Apoptosis also leads to the deletion of expanded effector T cells during immune responses. The dysregulation of apoptosis in the immune system results in autoimmunity, tumorogenesis and immunodeficiency. Two major pathways lead to apoptosis: the intrinsic cell death pathway controlled by Bcl-2 family members and the extrinsic cell death pathway controlled by death receptor signaling. These two pathways work together to regulate T lymphocyte development and function.