Objective To investigate the role and mechanism of heat shock protein 60 (HSP60) in induction of murine skin allograft tolerance. Methods At the age of 8-12 weeks, inbred female BALB/C (H-2d) mice (n=45) and CBA/N (H-2k)mice (n=15) were used as transplantation donors and C57BL/6 (H-2b) mice (n=60) as recipients. Recipients C57BL/6 (H-2b) mice were randomized into 4 groups (n=15). In group A, 1 cm × 1 cm Wolfe-Krause skin graft was excised from the back of BALB/C (H-2d) mice and hypoderma was scraped off aseptically, and then transplanted to the back of C57BL/6 (H-2b)mice. The method of skin transplantation in the other 3 groups was the same as to group A. In group B, C57BL/6 (H-2b) mice were treated with imcompleted Freund’s adjuvant (IFA) administration into the back 2 weeks before transplantation of BALB/C (H-2d) mice skin. In group C, C57BL/6 (H-2b) mice were administered HSP60 emulsified in IFA into the back 2 weeks before transplantation of BALB/C (H-2d) mice skin. In group D, C57BL/6 (H-2b) mice were treated with HSP60 emulsified in IFA into the back and followed by skin transplantation of CBA/N (H-2k) mice 2 weeks later. The delayed type hypersensitivity was determined 7 days after transplantation. One-way mixed lymphocyte reaction, the concentration of cytokines in the mixed lymphocyte reaction culture supernatant was determined 7 days and 25 days after transplantation. The survival time of skin allograft was observed. Results The survival time of skin allograft in groups A, B, C and D was 12.4 ± 0.5, 11.6 ± 0.8, 29.3 ± 2.6 and 27.6 ± 2.1 days, respectively. There was significant difference between groups A, B and groups C, D (P﹤0.05), while there was no significant difference between group A and group B as well as between group C and group D (P gt; 0.05). The counts of per minute impulse (cpm) of mixed lymphocyte reaction 7 days after transplantation in groups A, B, C and D was 12 836 ± 1 357, 11 876 ±1 265, 6 581 ± 573 and 6 843 ± 612, respectively. There was significant difference between groups A, B and group C and group D (P lt; 0.05), while there was no significant difference between group A and group B as well as between group C and group D (P gt; 0.05). The cpm of mixed lymphocyte reaction at 25 days after transplantation in group A, B, C and D was 13 286 ±1 498, 12 960 ± 1 376, 11 936 ± 1 265 and 12 374 ± 1269, respectively. There was no significant difference among 4 groups (P gt;0.05).The concentration of IL-10 in the mixed lymphocyte reaction culture supernatant in groups C, D were higher than that in groups A, B, and IL-2 and IFN-γ were lower than that in groups A, B 7 days after transplantation (P lt; 0.05), while there was no significant difference between group A and group B as well as between group C and group D (P gt; 0.05). There was no significant difference in cytokines among the 4 groups 25 days after transplantation (P gt; 0.05). The delayed type hypersensitivity in groups A, B, C and D 7 days after transplantation was 0.84 ± 0.09, 0.81 ± 0.07, 0.43 ± 0.05 and 0.46 ± 0.03 mm, respectively. There was significant differences between groups A, B and groups C, D (P lt; 0.05). While there was no significant difference between group A and group B as well as between group C and group D (P gt; 0.05). Conclusion HSP60 may play a role in induction and maintenance of murine skin allograft tolerance.