HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Gregori, S. Articles by Adorini, L. Search for Related Content PubMed PubMed Citation Articles by Gregori, S. Articles by Adorini, L. Pubmed/NCBI databases Medline Plus Health Information Diabetes Type 1

A Peptide Binding Motif for I-E^g7, the MHC Class II Molecule That Protects E-Transgenic Nonobese Diabetic Mice from Autoimmune Diabetes¹

Silvia Gregori^*, Sylvie Trembleau^*, Giuseppe Penna^*, Fabio Gallazzi^*, Juergen Hammer^*, George K. Papadopoulos and Luciano Adorini^2,*

^* Roche Milano Ricerche, Milan, Italy; and Laboratory of Biochemistry and Biophysics, Technological Educational Institute of Epirus, Arta, Greece

The nonobese diabetic (NOD) mouse, a model of spontaneous insulin-dependent diabetes mellitus (IDDM), fails to express surface MHC class II I-E^g7 molecules due a deletion in the E gene promoter. E-transgenic NOD mice express the EEß^g7 dimer and fail to develop either insulitis or IDDM. A number of hypotheses have been proposed to explain the mechanisms of protection, most of which require peptide binding to I-E^g7. To define the requirements for peptide binding to I-E^g7, we first identified an I-E^g7-restricted T cell epitope corresponding to the sequence 4–13 of Mycobacterium tuberculosis 65-kDa heat shock protein (hsp). Single amino acid substitutions at individual positions revealed a motif for peptide binding to I-E^g7 characterized by two primary anchors at relative position (p) 1 and 4, and two secondary anchors at p6 and p9. This motif is present in eight of nine hsp peptides that bind to I-E^g7 with high affinity. The I-E^g7 binding motif displays a unique p4 anchor compared with the other known I-E motifs, and major differences are found between I-E^g7 and I-A^g7 binding motifs. Analysis of peptide binding to I-E^g7 and I-A^g7 molecules as well as proliferative responses of draining lymph node cells from hsp-primed NOD and E-transgenic NOD mice to overlapping hsp peptides revealed that the two MHC molecules bind different peptides. Of 80 hsp peptides tested, none bind with high affinity to both MHC molecules, arguing against some of the mechanisms hypothesized to explain protection from IDDM in E-transgenic NOD mice.

This article has been cited by other articles:

				S. Trembleau, S. Gregori, G. Penna, I. Gorny, and L. Adorini IL-12 Administration Reveals Diabetogenic T Cells in Genetically Resistant I-E{alpha}-Transgenic Nonobese Diabetic Mice: Resistance to Autoimmune Diabetes Is Associated with Binding of E{alpha}-Derived Peptides to the I-Ag7 Molecule J. Immunol., October 1, 2001; 167(7): 4104 - 4114. [Abstract] [Full Text] [PDF]

				E. A. Johnson, P. Silveira, H. D. Chapman, E. H. Leiter, and D. V. Serreze Inhibition of Autoimmune Diabetes in Nonobese Diabetic Mice by Transgenic Restoration of H2-E MHC Class II Expression: Additive, But Unequal, Involvement of Multiple APC Subtypes J. Immunol., August 15, 2001; 167(4): 2404 - 2410. [Abstract] [Full Text] [PDF]

				A. K. Moustakas, Y. van de Wal, J. Routsias, Y. M. C. Kooy, P. van Veelen, J. W. Drijfhout, F. Koning, and G. K. Papadopoulos Structure of celiac disease-associated HLA-DQ8 and non-associated HLA-DQ9 alleles in complex with two disease-specific epitopes Int. Immunol., August 1, 2000; 12(8): 1157 - 1166. [Abstract] [Full Text] [PDF]

				S. Gregori, E. Bono, F. Gallazzi, J. Hammer, L. C. Harrison, and L. Adorini The motif for peptide binding to the insulin-dependent diabetes mellitus-associated class II MHC molecule I-Ag7 validated by phage display library Int. Immunol., April 1, 2000; 12(4): 493 - 503. [Abstract] [Full Text] [PDF]