Plasmodium falciparum polypeptides interacting with human red cell membranes show high affinity binding to Band-3

P. falciparum proteins were labelled with [35S]methionine and harvested at various asexual stages. A number of parasite proteins bound to uninfected red cell membranes (ghosts). Some of these proteins differentially partitioned when ghosts were extracted with detergent. Several of these proteins bound very strongly to immobilised whole ghost proteins or immobilised purified Band-3 in a stage-specific manner, but not to a sham-coupled matrix or to immobilised Band-3 extract from cells rendered refractory to invasion. Such specific binding of parasite proteins to immobilised Band-3 supports recent conjecture as to its role as a host receptor during parasite invasion. However, our results demonstrate the complex and multifactorial nature of the interaction between parasite and host proteins during invasion and development.