Collagen-induced arthritis(CIA)is an animal model,which closely resembles human rheumatoid arthritis(RA)in pathogenesis and pathology.Evidence suggests that the inhibition of T lymphocytes or their functions can alleviate the progression of arthritis.So the administration of arthritogenic T cell receptor(TCR)variable region peptide or DNA vaccines encoding pathogenic TCR Vβvariable region may provide useful information for designing specific immunotherapies against autoimmune diseases.Heat shock proteins(HSPs)have the function of raising antigenic immunogenicity and HSP70 has a protective effect against arthritis.We previously demonstrated the presence of pathogenic predominant T cell receptor Vβ5.2 and Vβ8.2 clonotypes in the joints of CIA rats.In this study,we constructed the recombinant eukaryotic expression vectors pTARGET-TCR Vβ5.2/8.2-HSP70,and evaluated their protective effects on CIA rats.Protective effects were observed in CIA rats by injecting these recombinant DNA vaccines,which could alleviate arthritis index,decrease the levels of IFN-γand anti-CII antibody in serum,and increase the levels of IL-4.Pathological changes were not as serious as those observed in control CIA rats.The rat injected with two combined vaccines showed better protective effects than CIA rats administered with individual vaccine.These results showed that recombinant DNA vaccines pTARGET-TCR Vβ5.2-HSP70 and pTARGET-TCR Vβ8.2-HSP70 could significantly alleviate the arthritic symptoms of CIA rats,and better protective effects could be achieved if these two vaccines were used in combination. Collagen-induced arthritis (CIA) is an animal model, which closely resembles human rheumatoid arthritis (RA) in pathogenesis and pathology. Evidence suggests that the inhibition of T lymphocytes or their functions can alleviate the progression of arthritis. So the administration of arthritogenic T Cell receptor (TCR) variable region peptide or DNA vaccines encoding pathogenic TCR Vβvariable regions may provide useful information for designing specific immunotherapies against autoimmune diseases. Heat shock proteins (HSPs) have the function of raising antigenic immunogenicity and HSP70 has a protective effect against arthritis. We previously demonstrated the presence of pathogenic predominant T cell receptor Vβ5.2 and Vβ8.2 clonotypes in the joints of CIA rats. In this study, we constructed the recombinant eukaryotic expression vectors pTARGET-TCR Vβ5.2 / 8.2-HSP70, and their protective effects on CIA rats. Protective effects were observed in CIA rats by injecting these recombinant DNA vaccin es, which could alleviate arthritis index, decrease the levels of IFN-γand anti-CII antibody in serum, and increase the levels of IL-4.Pathological changes were not as serious as those observed in control CIA rats. combined vaccines showed better protective effects than CIA rats administered with individual vaccine. The results showed that recombinant DNA vaccines pTARGET-TCR Vβ5.2-HSP70 and pTARGET-TCR Vβ8.2-HSP70 could significantly alleviate the arthritic symptoms of CIA rats, and better protective effects could be achieved if these two vaccines were used in combination.