Akt provides the CD28 costimulatory signal for up-regulation of IL-2 and IFN-gamma but not TH2 cytokines

Nat Immunol. 2001 Jan;2(1):37-44. doi: 10.1038/83144.


A region of the interleukin-2 (IL-2) promoter known as the RE/AP element is activated in concert by signals that originate from the T cell antigen receptor and the CD28 coreceptor. We show here that the serine-threonine kinase Akt can provide a costimulatory signal for RE/AP activation that is indistinguishable from the signal provided by CD28. This includes the ability of Akt, like antibodies to CD28, to synergize with protein kinase C theta (PKC-theta) in the induction of RE/AP. Retrovirus-mediated expression of activated Akt in primary T cells from CD28-deficient mice is capable of selectively restoring production of IL-2 and interferon gamma, but not IL-4 or IL-5. Our results provide evidence that CD28 costimulation of different cytokines is mediated by discrete signaling pathways, one of which includes Akt.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • CD28 Antigens / metabolism*
  • Cell Line
  • Cytokines / metabolism
  • Humans
  • Interferon-gamma / biosynthesis*
  • Interleukin-2 / biosynthesis*
  • Mice
  • Mice, Inbred BALB C
  • Mice, Knockout
  • Mice, Transgenic
  • Models, Biological
  • Phosphatidylinositol 3-Kinases / metabolism
  • Phosphorylation
  • Protein-Serine-Threonine Kinases*
  • Proto-Oncogene Proteins / metabolism*
  • Proto-Oncogene Proteins c-akt
  • Receptors, Antigen, T-Cell / metabolism
  • Signal Transduction
  • T-Lymphocytes / immunology
  • Th2 Cells / immunology
  • Up-Regulation


  • CD28 Antigens
  • Cytokines
  • Interleukin-2
  • Proto-Oncogene Proteins
  • Receptors, Antigen, T-Cell
  • Interferon-gamma
  • Phosphatidylinositol 3-Kinases
  • AKT1 protein, human
  • Protein-Serine-Threonine Kinases
  • Proto-Oncogene Proteins c-akt