Objective: To clone and express a novel protein analogous to TIP (T cell immunomodulatory protein) of Plasmodium berghei ANKA and prepare its polyclonal antibody.
Methods: The PbTIP encoding nucleotide sequence was searched from the Plasmodium berghei genomic database and amplified by PCR. The gene was sub-cloned into prokaryotic expression vector pGEX4T-1 and expressed in E.coli BL21 (DE3). After induction by IPTG, the expression of PbTIP-GST fusion protein was characterized by SDS-PAGE and Western blotting. The inclusion bodies of GST-PbTIP fusion protein were injected into BALB/c mouse. Anti-sera were identified by indirect fluorescent antibody test and western blotting.
Results: The PbTIP-GST fusion protein was successfully expressed in the form of inclusion bodies, by controlling the temperature and concentration of IPTG. Anti-PbTIP-GST sera were acquired with high titer. The sera specifically recognized the PbTIP with a band of 60 000 in P.berghei infected erythrocyte protein.
Conclusion: PbTIP/GST fusion protein and polyclonal antibody have been obtained.