A 43 kDa recombinant plasmepsin elicits immune response in mice against Plasmodium berghei malaria

Intraerythrocytic parasites degrade haemoglobin to make available nutrients for their growth and maturation. Plasmepsins, the aspartic proteases of Plasmodium play a significant role in haemoglobin degradation and are proposed as attractive drug targets. In the present study the gene which encodes plasmepsin in rodent malaria parasite, Plasmodium berghei, was cloned and expressed. The gene was sequenced and expressed in Escherichia coli BL21DE3 and a recombinant plasmepsin of molecular weight 43 kDa was obtained. The sequence obtained was analysed and compared with plasmepsins of other Plasmodium spp. Mice immunized with the recombinant plasmepsin induced a strong humoral immune response. ELISA and IFA performed on the serum of immunized mice showed high antibody titres. Along with this, in vivo study exhibited partial protection against P. berghei infection suggesting role of plasmepsin in malaria control.