The Journal of Experimental Medicine
PBL InterferonSource
  Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents

This Article
Right arrow Full Text (PDF, 1160K)
Right arrow Alert me when this article is cited
Right arrow Citation Map
Services
Right arrow Email this article
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new content in the JEM
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Matsushita, S.
Right arrow Articles by Nishimura, Y.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Matsushita, S.
Right arrow Articles by Nishimura, Y.
Social Bookmarking
 Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati  
What's this?

Journal of Experimental Medicine, Vol 180, 873-883, Copyright © 1994 by Rockefeller University Press


ARTICLES

Allele specificity of structural requirement for peptides bound to HLA- DRB1*0405 and -DRB1*0406 complexes: implication for the HLA-associated susceptibility to methimazole-induced insulin autoimmune syndrome

S Matsushita, K Takahashi, M Motoki, K Komoriya, S Ikagawa and Y Nishimura
Department of Neuroscience and Immunology, Kumamoto University Graduate School of Medical Sciences, Japan.

Self-peptides bound to HLA-DR4 (DRA-DRB1*0405 complex) were eluted from the purified DR4 complex, fractionated on reverse-phase HPLC, and subjected to NH2-terminal sequencing. Seven independent sequences were obtained, and all putative peptides synthesized bound to DRB1*0405 as well as DRB1*0406 complex, which differ only at DR beta residues 37, 57, 74, and 86. Binding assay using analogue peptides of a DR4 binder GSTVFDNLPNPE revealed that FxxLxN is an important anchor motif necessary for binding (where x is any amino acid), which was common to DRB1*0405 and 0406. Determination of the binding affinity of 60 synthetic AAFAALANAA-based analogue peptides showed that substituting F to W or C; L to F, W, or Y; and N to Q or S on AAFAALANAA changed the affinity substantially between DRB1*0405 and DRB1*0406. It is noteworthy that all patients with methimazole-induced insulin autoimmune syndrome are positive for DRB1*0406 and negative for DRB1*0405. Interestingly, the quantitative structural motif identified in this study predicted that 8TSICSLYQLE17 of human insulin alpha chain may bind specifically to DRB1*0406 using its 10IxxLxQ15 motif. Indeed, DRB1*0406 complex bound 8TSICSLYQLE17 with a high affinity, and in striking contrast, DRB1*0405 complex did not. Furthermore, a short-term T cell line specific to human insulin established from a DRB1*0406- bearing individual did show reactivity with a peptide fragment containing the 10IxxLxQ15 motif. Although this fragment probably exists at a very low level under normal physiological conditions due to the disulfide bond between flanking cysteine residues (6Cys-11Cys), a reducing compound such as methimazole may cleave the disulfide bond in vivo and allow DR alpha-DRB1*0406 complex on antigen-presenting cells to bind much of the linear fragment of insulin alpha chain, which may lead to the activation of self-insulin-specific T-helper cells.
Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati    What's this?


This article has been cited by other articles:



  Home | Help | Feedback | Subscriptions | Archive | Search
TABLE OF CONTENTS