... interactions regulating T-cell migration in the development of T-cell immunity and tolerance. 1 To whom correspondence should be addressed (email rachel.david00@imperial.ac.uk ). 6 6 2007 © The Authors Journal compilation © 2007 Biochemical Society 2007 CD28 co-stimulatory molecule...

... CD28 co-stimulation is blocked or not required. Recruitment and activation of PI3K by CD28 promotes survival by inducing increased expression of Bcl-X L . However, CD28 engages additional signals that regulate proliferation and interleukin-2 production independently of PI3K. Thus a model emerges...