Objective To explore the feasibility of allogeneic marrow stromal stem cells(MSCs) as seed cells to construct tissue engineered bone bydetecting the expressions of interleukin 2(IL-2) and IL-2 receptor in rhesus monkeys after implanting these tissue engineered bones.Methods Engineered bones were constructed with osteoblasts which derived from allogeneic MSCs and bio-derived materials in vitro, and then were implanted to bridge 2.5 cm segmental bone defects of left radius in 15 rhesus monkeys as experimental group, bioderived materials only were implanted to bridge same size defects of right radius as control group. Every 3 monkeys were sacrificed in the 1st, the 2nd, the 3rd, the 6th andthe 12th weeks postoperatively and the expressions of IL-2 and IL-2 receptor in blood and graft samples were detected quantitatively by enzymelinked immuneosorbent assay (ELISA).Results There was no significant difference in the contents of IL-2 and its receptor between 2 groups(P>0.05). The contents ofIL-2 and its receptor increased from the 2nd week and maintained high level from the 2nd to the 6th week, but decreased after 6 weeks.ConclusionTissue engineered bones constructed with allogeneic MSCs and bio-derived materials show low immunogenicity. Allogeneic MSCs may be used as seed cells to construct tissue engineered bone.