tailieunhanh - Báo cáo y học: "ignal 3 and its role in autoimmunity"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học General Psychiatry cung cấp cho các bạn kiến thức về ngành y đề tài: Signal 3 and its role in autoimmunity. | Arthritis Research Therapy Vol 6 No 1 Thomas Viewpoint Signal 3 and its role in autoimmunity Ranjeny Thomas Centre for Immunology and Cancer Research Princess Alexandra Hospital University of Queensland Brisbane Australia Corresponding author Ranjeny Thomas e-mail rthomas@ Received 6 Nov 2003 Accepted 21 Nov 2003 Published 19 Jan 2004 Arthritis Res Ther 2004 6 26-27 DOI ar1033 2004 BioMed Central Ltd Print ISSN 1478-6354 Online ISSN 1478-6362 What is the third signal Dendritic cells DCs are the professional antigen-presenting cells APCs of the body and as such play a key role in the signaling of T cells for effector responses to antigen. Various co-stimulatory and adhesive interactions between DCs and T cells are able to drive proliferative proinflam-matory cytokine and cytotoxic effector functions of T cells 1 . The effector response made to antigen presented by DCs depends on the co-stimulatory signals delivered to T cells along with the antigen signal presented in the context of MHC molecules 2 . Lafferty s concept of a second or co-stimulatory signal stands as a key model for our understanding of the generation of immunity and also for our understanding of the basis for peripheral tolerance 3 . In recent years through the study of interactions taking place at the immunological synapse at which T cells are signaled by antigen-bearing APCs several groups have studied the minimal requirements of CD4 and CD8 T cells for these effector functions. Mescher et al. for example have done so using a simple system of beads conjugated with MHC and antigen - whose density can be varied - signal 1 and various membrane co-stimula-tory molecules signal 2 such as CD80 86 or CD54 ICAM-1 . In this context they have shown for CD8 T cells that signals 1 and 2 are sufficient for proliferation and cytokine production but that a third signal IL-12 is required for cytotoxic effector function 4 . The authors indicate that IL-12 is not the only soluble factor which .