Abstract: Objective To study the immunogenicity of the small intestinal submucosa(SIS)and explore its feasibility as a scaffold for tissue engineering.Methods Healthy New Zealand rabbits were subjected to the study.Under general anesthesia,the SISwhich has been prepared into a size as 10 mm×4 mm×3 mm were implanted into the sacro-spine muscle in terms of sterility.The condition of the same rabbits before operation was designed as own control.The vein blood were gained from the rabbits oto-fringe vein after the operation of 1,4 and 8 weeks,and the dynamic changing of CD₄⁺ and CD₈⁺ cell in peripheral blood were detected by flow cytometry.Then the immunity talkback of rabbits responded to the implanted SISwere observed.Results The results of immunology showed that the CD₄⁺ and CD₈⁺ cells of peripheral blood rised after implanting the de-antigene SISto the rabbits,and reach the peak after one week.The percent of CD₄⁺ and CD₈⁺ cells were significantly different from those of before implanting(P<0.05),and then fall to the least after four weeks.There was no significant difference between them and those of before operation.On the contrary,the group of the fresh SISindicated that the percent of CD₄⁺ and CD₈⁺ cells were step up continually.Between the two groups,the difference was significant(P<0.05).Conclusion The T-cell responses of different subsets following SISengrafts demonstrated only mild immunogenicities,which suggests an encouraging potential of SISas a scaffold for tissue engineering.

Key words: small intestinal submucosa, immunogenicity, tissue engineering