Affinity purification of CD36 with immobilized rC1-2 and fragments of rC1-2 [1-233]. Soluble receptors were incubated with bead-immobilized GST fusion recombinant proteins derived from the sequence of MC PfEMP1. Binding of CD36 and other host receptors was detected by Western blotting. (A) CD36 specifically binds to immobilized rC1-2 and not to GST or to other GST-fusion proteins (Fig 1) from the MC PfEMP1. rF1-2 was tested as an MBP-fusion protein. (B) Immobilized rC1-2 specifically binds CD36 and not other host cell receptors: P-Selectin, E-Selectin (ELAM-1), VCAM-1, and ICAM-1. These receptors do not mediate adherence of MC strain PE. (C) Deletion fragments of rC1-2 [1-233] were amplified by PCR with the appropriate primers, expressed in E coli and immobilized on Ab coated beads directly from 50 μL of bacterial lysate. CD36 binds to the 233 amino acid rC1-2 fragment of MC PfEMP1, denoted rC1-2 [1-233], and to a fragment representing a 41 amino acid deletion from the carboxy terminus, denoted rC1-2 [1-192]. Other fragments of rC1-2, including deletions from the amino or the carboxy end of rC1-2 and mutant forms in which cysteine residues were replaced with serine were also tested. These results are summarized in Table 1.