After transfection of pPTA1/Ig into COS 7 cells by DEAE dextran, expression of a secreting fusion protein was identified by affinity chromatography and sandwich ELISA assay with anti PTA1 mAb and HRP anti hIgFc mAb.

• 重组载体通过DEAE?dextran法转染COS?7细胞，经夹心ELISA及亲和层析、SDS?PAGE鉴定融合蛋白的表达及免疫学活性。