Reduced self-reactivity of an autoreactive T cell after activation with cross-reactive non-self-ligand.
Autoreactive CD4(+) T lymphocytes are critical to the induction of autoimmune disease, but because of the degenerate nature of T cell receptor (TCR) activation such receptors also respond to other ligands. Interaction of autoreactive T cells with other non-self-ligands has been shown to activate and expand self-reactive cells and induce autoimmunity. To understand the effect on the autoreactivity of naive cross-reactive T cells of activation with a potent nonself ligand, we have generated a TCR transgenic mouse which expresses a TCR with a broad cross-reactivity to a number of ligands including self-antigen. The activation of naive transgenic recombination activating gene (Rag)2(-)(/)(-) T cells with a potent non-self-ligand did not result in a enhancement of reactivity to self, but made these T cells nonresponsive to the self-ligand and anti-CD3, although they retained a degree of responsiveness to the non-self-ligand. These desensitized cells had many characteristics of anergic T cells. Interleukin (IL)-2 production was selectively reduced compared with interferon (IFN)-gamma. p21(ras) activity was reduced and p38 mitogen-activated protein kinase (MAPK) was relatively spared, consistent with known biochemical characteristics of anergy. Surprisingly, calcium fluxes were also affected and the anergic phenotype could not be reversed by exogenous IL-2. Therefore, activation with a hyperstimulating non-self-ligand changes functional specificity of an autoreactive T cell without altering the TCR. This mechanism may preserve the useful reactivity of peripheral T cells to foreign antigen while eliminating responses to self.
Munder
Markus
M
Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
Bettelli
Estelle
E
Monney
Laurent
L
Slavik
Jacqueline M
JM
Nicholson
Lindsay B
LB
Kuchroo
Vijay K
VK
D000595:Amino Acid Sequence; D000818:Animals; D017252:CD3 Complex; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002118:Calcium; D003429:Cross Reactions; D005260:Female; D048031:JNK Mitogen-Activated Protein Kinases; D008024:Ligands; D008213:Lymphocyte Activation; D008565:Membrane Proteins / Q000276:immunology; D051379:Mice; D008822:Mice, Transgenic; D019950:Mitogen-Activated Protein Kinase 1 / Q000276:immunology; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000276:immunology; D008969:Molecular Sequence Data; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000276:immunology; D016283:Proto-Oncogene Proteins p21(ras) / Q000276:immunology; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D051746:ZAP-70 Protein-Tyrosine Kinase
D017252:CD3 Complex; C115335:CD3E protein, human; D008024:Ligands; D008565:Membrane Proteins; D011948:Receptors, Antigen, T-Cell; C054979:antigen T cell receptor, zeta chain; D011505:Protein-Tyrosine Kinases; D051746:ZAP-70 Protein-Tyrosine Kinase; C497262:Zap70 protein, mouse; D048031:JNK Mitogen-Activated Protein Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D016283:Proto-Oncogene Proteins p21(ras); D002118:Calcium