Diabetes, Vol 45, Issue 9 1168-1172, Copyright © 1996 by American Diabetes Association
The hsp60 peptide p277 arrests the autoimmune diabetes induced by the toxin streptozotocin
D Elias and IR Cohen
Department of Cell Biology, Weizmann Institute of Science, Rehovot, Israel.
The development of autoimmune diabetes in the NOD strain of mice (H-2g7) is
marked by the presence of T-cells reactive to the p277 peptide of the
6O-kDa heat shock protein (hsp60). We have found that the p277 peptide can
be used as a therapeutic vaccine to arrest NOD diabetes. Recently, we found
that T-cell autoimmunity to p277 also develops spontaneously in C57BL/KsJ
mice (H-2d) during the induction of autoimmune diabetes by a very low dose
of the beta-cell toxin streptozotocin (STZ). We now report the inhibition
of STZ toxin-induced autoimmune diabetes by p277 peptide therapy.
Administration of two doses each of 100 micrograms of peptide p277 in
mineral oil given 1 week after toxin induction and 85 days later was most
effective. The effect of p277 on STZ toxin-induced diabetes was marked by a
shift in p277 autoimmunity from a T-cell proliferative response to the
production of anti-p277 antibodies. The anti-p277 antibodies were
predominantly of the IgG1 and IgG2b isotypes, known to be regulated by Th2
type cytokines; IgG2a antibody, known to be dependent on interferon
(IFN)-gamma, was induced to a much lesser degree. Peptide p277 therapy was
specific: treatment of the mice with an immunogenic peptide from the
sequence of another antigen, GADp34, failed to prevent the development of
diabetes. The GADp34 peptide induced lower titers of specific antibodies,
and the antibodies were predominantly of the IgG2a class. Thus, p277
peptide therapy, marked by the induction of Th2-type antibodies, can be
effective in toxin-induced autoimmune diabetes.