The immune system has developed a number of mechanisms for recognizing foreign antigen while ignoring self-antigens. However, the presence of autoimmune diseases demonstrates these mechanisms can be bypassed. Our laboratory has demonstrated that the posttranslational modification of aspartic acid to isoaspartic acid in self-peptides induces immunogenicity to otherwise immunologically ignored peptides. Isoaspartyl residues occur spontaneously at physiological conditions and increase in aged or stressed cells. The proposed studies will examine how isoaspartyl containing self-peptides/proteins break tolerance and contribute to autoimmunity. This will be achieved by 1) examining T and B cell responses to isoaspartyl and normal forms of self-antigens, 2) determining the effect of isoaspartyl accumulation on immune function in mice deficient in the isoaspartyl repair enzyme PCMT, and 3) examining the spontaneous development of autoimmunity and pathology in PCMT -I- mice alone and backcrossed to a murine model of systemic lupus erythematosus (SLE). Results of these studies will be helpful in developing immunotherapies for the modulation of autoimmunity.

Agency
National Institute of Health (NIH)
Institute
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
Type
Postdoctoral Individual National Research Service Award (F32)
Project #
5F32AR047759-02
Application #
6534529
Study Section
Special Emphasis Panel (ZRG1-IMB (20))
Program Officer
Gretz, Elizabeth
Project Start
2002-08-31
Project End
Budget Start
2002-08-31
Budget End
2003-08-30
Support Year
2
Fiscal Year
2002
Total Cost
$48,148
Indirect Cost
Name
Yale University
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
082359691
City
New Haven
State
CT
Country
United States
Zip Code
06520
Reissner, Kathryn J; Paranandi, Mallik V; Luc, Trang M et al. (2006) Synapsin I is a major endogenous substrate for protein L-isoaspartyl methyltransferase in mammalian brain. J Biol Chem 281:8389-98
Zhu, Jeff X; Doyle, Hester A; Mamula, Mark J et al. (2006) Protein repair in the brain, proteomic analysis of endogenous substrates for protein L-isoaspartyl methyltransferase in mouse brain. J Biol Chem 281:33802-13
Doyle, Hester A; Gee, Renelle J; Mamula, Mark J (2003) A failure to repair self-proteins leads to T cell hyperproliferation and autoantibody production. J Immunol 171:2840-7
Doyle, Hester A; Mamula, Mark J (2002) Posttranslational protein modifications: new flavors in the menu of autoantigens. Curr Opin Rheumatol 14:244-9
Doyle, H A; Mamula, M J (2001) Post-translational protein modifications in antigen recognition and autoimmunity. Trends Immunol 22:443-9
Young, A L; Carter, W G; Doyle, H A et al. (2001) Structural integrity of histone H2B in vivo requires the activity of protein L-isoaspartate O-methyltransferase, a putative protein repair enzyme. J Biol Chem 276:37161-5
Doyle, H A; Yan, J; Liang, B et al. (2001) Lupus autoantigens: their origins, forms, and presentation. Immunol Res 24:131-47