CTLA-4: a moving target in immunotherapy

Behzad Rowshanravan, Neil Halliday and David M. Sansom


CD28 and CTLA-4 are members of a family of Immunoglobulin-related receptors that are responsible for various aspects of T cell immune regulation. The family includes CD28, CTLA-4 and ICOS as well as other proteins including PD-1, BTLA and TIGIT. These receptors have both stimulatory (CD28, ICOS) as well as inhibitory roles (CTLA-4, PD-1, BTLA and TIGIT) in T cell function. Increasingly these pathways are targeted as part of immune modulatory strategies to treat cancers, referred to generically as immune checkpoint blockade, and conversely to treat autoimmunity and CTLA-4 deficiency. Here we focus on the biology of the CD28/CTLA-4 pathway as a framework for understanding the impacts of therapeutic manipulation of this pathway.

  • Submitted June 26, 2017.
  • Accepted July 31, 2017.