The genes encoding antibody heavy and light chain variable regions (VH and VL) were cloned by RT PCR from OKT3 hybridoma cells, which produced anti CD3 moleclonal antibody. The VH and VL genes were fused and become a single chain Fv (scFv). The scFv gene was cloned into pCANTAB5E vector and expressed on bacterial phage surface. By three panning rounds, we have obtained two single chain antibodys that specific for CD3. The anti CD3 scFv will be a reagent for diagnosis and therapy of immuno disorder 肾缺血再灌注损伤中CD11a及髓过氧化酶的变化 Abstract AIM: To investigate the change of CD11a and myeloperoxidase (MPO) content during rat renal ischemia-reperfusion injury (IRI), as well as the role of LFA 1 in renal IRI. METHODS:We utilized the rat model of renal IRI to detect the renal tissue contents of CD11a and MPO. RESULTS: Level of CD11a and MPO was very low in normal renal tissue, but was increased significantly in those of ischemia reperfusion. And this level in the ischemia 60 min reperfusion group was higher than that in ischemia 30 min reperfusion group. CONCLUSION: Level of CD11a and MPO in rat renal tissue increased significantly during rat renal IRI. LFAK 1 mediated leukocyte adherence plays an important role in renal IRI.