CYTOADHERENCE CHARACTERISTICS OF PLASMODIUM-FALCIPARUM ISOLATES FROM THAILAND - EVIDENCE FOR CHONDROITIN SULFATE A AS A CYTOADHERENCE RECEPTOR

The association between cytoadherence of Plasmodium falciparum-infecte d erythrocytes and the severity of malaria has been evaluated. In this study, we investigate adherence to C32 melanoma cells, CD36, intracel lular adhesion molecule-1 (ICAM-1), thrombospondin (TSP), E-selectin, vascular cell adhesion molecule-1 (VCAM-1), and chondroitin sulfate A (CSA) of 36 P. falciparum isolates from patients suffering from acute falciparum malaria. Adherence to purified adhesion molecules varied gr eatly among different parasite isolates. All isolates but one adhered to CD36, but none bound to E-selectin and VCAM-1 beyond control levels . Some P. falciparum isolates adhered to ICAM-1 and to CSA, a newly id entified receptor for adherence. There was no correlation between in v itro binding to any one receptor and the patients' conditions. In addi tion, we investigated the characteristics of adherence to CSA and to C 32 melanoma cells. Infected erythrocytes continued to adhere after try psin digestion and soluble CSA inhibited adherence to C32 melanoma cel ls in a dose-dependent manner. The results imply a role for CSA in the natural infection of P. falciparum.