The reverse stop-signal model for CTLA4 function
1Cell Signalling Section, Division of Immunology, Department of Pathology, Tennis Court Road, CB1 4QP Cambridge, UK. cer51@cam.ac.uk
Abstract:
Activation of the T-cell co-receptor cytotoxic T-lymphocyte antigen 4 (CTLA4) has a pivotal role in adjusting the threshold for T-cell activation and in preventing autoimmunity and massive tissue infiltration by T cells. Although many mechanistic models have been postulated, no single model has yet accounted for its overall function. In this Opinion article, I outline the strengths and weaknesses of the current models, and present a new 'reverse stop-signal model' to account for CTLA4 function.
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