Naturally occurring anti-band 3 autoantibodies recognize a high molecular weight protein on the surface of Plasmodium falciparum infected erythrocytes.

Naturally occurring anti-band 3 autoantibodies bind to erythrocytes infected with a knobby variant of the human malaria Plasmodium falciparum (FCR-3 strain). The autoantibodies recognized a greater than 240 kDa protein in SDS extracts made from surface iodinated infected erythrocytes. The antigen was associated only with erythrocytes infected with a knobby variant, and was removed by trypsin treatment of intact infected cells. By two-dimensional peptide map analysis the antigen was shown to be structurally related to the human erythrocyte anion transporter, band 3.