Cloning, expression and identification of M2 autoantigen and its trimer / 中华消化杂志

ABSTRACT

Objective To express the immunodominant epitopes of the branched chain 2 oxo acid dehydrogenase complex (BCOADC), the pyruvate dehydrogenase complex (PDC), the 2 oxo glutarate dehydrogenase complex (OGDC) and a triple hybrid clone (designated as BPO), and use BPO as a tool for the detection of M2 specific for primary biliary cirrhosis (PBC). Methods The cDNA fragments encoding the M2 reactive epitopes of BCOADC, PDC and OGDC were amplified using PCR with total RNA extracted from human peripheral mononuclear blood cell. The fragments were cloned into pQE 30 and then transformed into plasmid E.coli M15. Its products were induced by isopropylthio ? D galactoside and confirmed with SDS PAGE and Western blot. Results Four specific proteins induced from the transformants containing the fused plasmid were shown to have antigenic reactivity with PBC sera, but not with normal control sera. Conclusions We succeeded in expressing three immunodominant epitopes and a hybrid clone which can be used as a powerful and specific method for the diagnosis of PBC.