PLASMODIUM-FALCIPARUM - NATURALLY-OCCURRING RABBIT IMMUNOGLOBULINS RECOGNIZE HUMAN BAND-3 PEPTIDE MOTIFS AND MALARIA-INFECTED RED-CELLS

The reactivity to overlapping decapeptides based on sequences of human band 3 protein was determined for 24 rabbit serum samples. A high per centage of the sera recognized sequences of amino acid 650-670, as wel l as several other sequences representing putative exofacial regions o f the band 3 protein. When sera were used to stain immunofluorescently human erythrocytes, some of which were infected with P. falciparum, t hose samples that predominantly reacted with amino acids 650-670 stain ed P. falciparum-infected red cells, whereas those that reacted with o ther regions of band 3 stained all erythrocytes. A positive correlatio n was found between anti-band 3 reactivity and the capacity of a serum to inhibit the cytoadherence of P. falciparum-infected erythrocytes t o C32 amelanotic melanoma cells. Also, some rabbit sera immunoprecipit ated a high-molecular-weight protein from extracts of surface iodinate d P. falciparum-infected red cells. (C) 1996 Academic Press, Inc.