Inhibition of adjuvantinduced arthritis by DNA vaccination with the 70-kd or the 90-kd human heatshock protein: immune cross-regulation with the 60-kd heat-shock protein

Objective. Adjuvant arthritis can be induced in Lewis rats by immunization with Mycobacterium tuber-culosis (Mt). The mycobacterial 65-kd heat-shock pro-tein (Hsp65) is targeted by arthritogenic T cells. How-ever, Hsp65 and the mycobacterial 71-kd heat-shock protein are also recognized by T cells that can down-regulate adjuvant-induced arthritis (AIA). We have recently demonstrated that vaccination with human Hsp60 DNA inhibits AIA. The present study was under-taken to analyze the role of the T cell responses to self HSP molecules other than Hsp60 in the control of AIA. Methods. Lewis rats were immunized with DNA vaccines coding for human Hsp70 or Hsp90 (Hsp70 plasmid [pHsp70] or pHsp90), and AIA was induced. The T cell response to Mt, Hsp60, Hsp70, and Hsp9