TY - JOUR
T1 - Cross-reactive mycobacterial and self hsp60 epitope recognition in I-Ag7 expressing NOD, NOD-asp and Biozzi AB/H mice
AU - Van Halteren, Astrid G.S.
AU - Roep, Bart O.
AU - Gregori, Silvia
AU - Cooke, Anne
AU - Van Eden, Willem
AU - Kraal, Georg
AU - Wauben, Marca H.M.
N1 - Funding Information:
This work was supported by grant 96.116 of the Diabetes Fonds Nederland.
PY - 2002/3
Y1 - 2002/3
N2 - The highly conserved 60kD endogenous heat shock protein (hsp60) has been suggested to be a target for T cell recognition in autoimmune diseases such as type I diabetes. We previously reported cross-recognition of both mycobacterial hsp60 (Mt60) and self hsp60 (m60) by Mt60 immunized NOD mice. To identify the epitopes involved, we generated T cell lines against m60 or its mycobacterial counterpart and tested these lines for recognition of complete sets of overlapping peptides spanning either hsp60 sequence. T cell lines responded to identical regions in the hsp60 proteins, regardless of their degree of conservation or I-Ag7 binding-affinity. Additionally, we determined whether a protective genetic background would affect the presence of hsp60 cross-reactive T cells in the peripheral repertoire by comparing epitope recognition in I-Ag7 expressing NOD, NOD-asp and Biozzi AB/H mice. Two out of five immunodominant murine peptides were able to induce proliferation in NOD and NOD-asp Mt60 T cell lines, but not in Biozzi AB/H T cell lines. Our results point out that Mt60 immunization not necessarily leads to proliferative T cells responding to endogenous hsp60 peptides in the context of diabetes-predisposing I-Ag7. Moreover, the capacity of T cells to respond to self hsp60 is not influenced by the presence of protective I-Ag7asp. Yet, proliferation of hsp60 autoreactive T cells is solely measured in combination with insulitis and as such serves as a surrogate marker for islet inflammation.
AB - The highly conserved 60kD endogenous heat shock protein (hsp60) has been suggested to be a target for T cell recognition in autoimmune diseases such as type I diabetes. We previously reported cross-recognition of both mycobacterial hsp60 (Mt60) and self hsp60 (m60) by Mt60 immunized NOD mice. To identify the epitopes involved, we generated T cell lines against m60 or its mycobacterial counterpart and tested these lines for recognition of complete sets of overlapping peptides spanning either hsp60 sequence. T cell lines responded to identical regions in the hsp60 proteins, regardless of their degree of conservation or I-Ag7 binding-affinity. Additionally, we determined whether a protective genetic background would affect the presence of hsp60 cross-reactive T cells in the peripheral repertoire by comparing epitope recognition in I-Ag7 expressing NOD, NOD-asp and Biozzi AB/H mice. Two out of five immunodominant murine peptides were able to induce proliferation in NOD and NOD-asp Mt60 T cell lines, but not in Biozzi AB/H T cell lines. Our results point out that Mt60 immunization not necessarily leads to proliferative T cells responding to endogenous hsp60 peptides in the context of diabetes-predisposing I-Ag7. Moreover, the capacity of T cells to respond to self hsp60 is not influenced by the presence of protective I-Ag7asp. Yet, proliferation of hsp60 autoreactive T cells is solely measured in combination with insulitis and as such serves as a surrogate marker for islet inflammation.
KW - Autoimmunity
KW - Diabetes
KW - Repertoire development
KW - Transgenic mice
UR - http://www.scopus.com/inward/record.url?scp=0036525462&partnerID=8YFLogxK
U2 - 10.1006/jaut.2001.0578
DO - 10.1006/jaut.2001.0578
M3 - Article
C2 - 11908946
AN - SCOPUS:0036525462
SN - 0896-8411
VL - 18
SP - 139
EP - 147
JO - Journal of Autoimmunity
JF - Journal of Autoimmunity
IS - 2
ER -