Yang Cheng 1 , 2 , 3 , Feng Lu 1 , 4 , Bo Wang 1 , 5 , Jian Li 1 , 6 , Jin-Hee Han 1 , Daisuke Ito 3 , 7 , Deok-Hoon Kong 8 , Lubin Jiang 9 , Jian Wu 3 , Kwon-Soo Ha 8 , Eizo Takashima 7 , Jetsumon Sattabongkot 10 , Jun Cao 4 , Myat Htut Nyunt 1 , 11 , Myat Phone Kyaw 11 , Sanjay A. Desai 3 , Louis H. Miller 3 , Takafumi Tsuboi a , 7 , Eun-Taek Han b , 1
19 October 2016
Plasmodium vivax, a major agent of malaria in both temperate and tropical climates, has been thought to be unable to infect humans lacking the Duffy (Fy) blood group antigen because this receptor is critical for erythrocyte invasion. Recent surveys in various endemic regions, however, have reported P. vivax infections in Duffy-negative individuals, suggesting that the parasite may utilize alternative receptor-ligand pairs to complete the erythrocyte invasion. Here, we identified and characterized a novel parasite ligand, Plasmodium vivax GPI-anchored micronemal antigen (PvGAMA), that bound human erythrocytes regardless of Duffy antigen status. PvGAMA was localized at the microneme in the mature schizont-stage parasites. The antibodies against PvGAMA fragments inhibited PvGAMA binding to erythrocytes in a dose-dependent manner. The erythrocyte-specific binding activities of PvGAMA were significantly reduced by chymotrypsin treatment. Thus, PvGAMA may be an adhesion molecule for the invasion of Duffy-positive and -negative human erythrocytes.