title: DNA vaccine containing the mycobacterial hsp65 gene prevented insulitis in MLD-STZ diabetes.
abstract: BACKGROUND
  Our group previously demonstrated that a DNA plasmid encoding the mycobacterial 65-kDa heat shock protein (DNA-HSP65) displayed prophylactic and therapeutic effect in a mice model for tuberculosis. This protection was attributed to induction of a strong cellular immunity against HSP65. As specific immunity to HSP60 family has been detected in arthritis, multiple sclerosis and diabetes, the vaccination procedure with DNA-HSP65 could induce a cross-reactive immune response that could trigger or worsen these autoimmune diseases.
  
  
  METHODS
  In this investigation was evaluated the effect of a previous vaccination with DNA-HSP65 on diabetes development induced by Streptozotocin (STZ). C57BL/6 mice received three vaccine doses or the corresponding empty vector and were then injected with multiple low doses of STZ.
  
  
  RESULTS
  DNA-HSP65 vaccination protected mice from STZ induced insulitis and this was associated with higher production of IL-10 in spleen and also in the islets. This protective effect was also concomitant with the appearance of a regulatory cell population in the spleen and a decreased infiltration of the islets by T CD8+ lymphocytes. The vector (DNAv) also determined immunomodulation but its protective effect against insulitis was very discrete.
  
  
  CONCLUSIONS
  The data presented in this study encourages a further investigation in the regulatory potential of the DNA-HSP65 construct. Our findings have important implications for the development of new immune therapy strategies to combat autoimmune diseases.
authors.affiliation: University of São Paulo, Ribeirão Preto Medical School, Department of Biochemistry and Immunology, Ribeirão Preto, São Paulo, Brazil. clsilva@fmrp.usp.br.
authors.forename: Rubens R
authors.initials: RR
authors.lastname: Santos
authors.forename: Alexandrina
authors.initials: A
authors.lastname: Sartori
authors.forename: Deison S
authors.initials: DS
authors.lastname: Lima
authors.forename: Patrícia Rm
authors.initials: PR
authors.lastname: Souza
authors.forename: Arlete Am
authors.initials: AA
authors.lastname: Coelho-Castelo
authors.forename: Vânia Ld
authors.initials: VL
authors.lastname: Bonato
authors.forename: Célio L
authors.initials: CL
authors.lastname: Silva