SULFATED GLYCOCONJUGATES AS DISRUPTERS OF PLASMODIUM-FALCIPARUM ERYTHROCYTE ROSETTES

Some strains of Plasmodium falciparum form erythrocyte rosettes that a re believed to result from a lectin interaction between malaria-infect ed and uninfected erythrocytes. The sulfated glycoconjugate heparin an d certain heparin derivatives have been observed to disrupt rosettes. To investigate this interaction further, we have studied the effects o f four sulfated glycoconjugates on 15 fresh isolates of P. falciparum from Papua New Guinea. A broader range of sulfated glycoconjugates has been tested against a laboratory strain. A concentration of 1,000 mu g/ml of dextran sulfate (molecular weight [MW] 500,000) was the most p otent disrupter of rosettes. Fucoidan, heparin, and dextran sulfate (M W 5,000) were of decreasing effectiveness in 14 of 15 fresh isolates. The same relationship was true for the laboratory strain. Pentosan pol ysulfate and sulfatide also disrupted rosettes; chondroitin sulfates A , B, and C and keratan sulfate gave either minimal or no rosette disru ption. Thus, some sulfated glycoconjugates are potent disrupters of P. falciparum erythrocyte rosettes. Sulfated glycoconjugaes that are pot ent disrupters of P. falciparum rosettes may prove useful in identifyi ng ligands involved in rosette formation.