Identification of an erythrocyte binding peptide from the erythrocyte binding antigen, EBA-175, which blocks parasite multiplication and induces peptide-blocking antibodies
Research output: Contribution to journal › Journal article › Research › peer-review
A biotinylated peptide covering a sequence of 21 amino acids (aa) from the erythrocyte binding antigen (EBA-175) of Plasmodium falciparum bound to human glycophorin A, an erythrocyte receptor for merozoites, as demonstrated by enzyme-linked immunosorbent assay (ELISA) and to erythrocytes as demonstrated by flow cytometry analysis. The peptide, EBA(aa1076-96), also bound to desialylated glycophorin A and glycophorin B when tested by ELISA. The peptide blocked parasite multiplication in vitro. The glycophorin A binding sequence was further delineated to a 12-aa sequence, EBA(aa1085-96), by testing the binding of a range of truncated peptides to immobilized glycophorin A. Our data indicate that EBA(aa1085-96) is part of a ligand on the merozoite for binding to erythrocyte receptors. This binding suggests that the EBA(aa1085-96) peptide is involved in a second binding step, independent of sialic acid. Antibody recognition of this peptide sequence may protect against merozoite invasion, but only a small proportion of sera from adults from different areas of malaria transmission showed antibody reactivities to the EBA(aa1076-96) peptide, indicating that this sequence is only weakly immunogenic during P. falciparum infections in humans. However, Tanzanian children with acute clinical malaria showed high immunoglobulin G reactivity to the EBA(aa1076-96) peptide compared to children with asymptomatic P. falciparum infections. The EBA(aa1076-96) peptide sequence from EBA-175 induced antibody formation in mice after conjugation of the peptide with purified protein derivative. These murine sera inhibited EBA(aa1076-96) peptide binding to glycophorin A.
Original language | English |
---|---|
Journal | Infection and Immunity |
Volume | 66 |
Issue number | 9 |
Pages (from-to) | 4203-4207 |
Number of pages | 4 |
ISSN | 0019-9567 |
Publication status | Published - 1998 |
Bibliographical note
Keywords: Adolescent; Adult; Aged; Aged, 80 and over; Amino Acid Sequence; Animals; Antibodies, Protozoan; Antigens, Protozoan; Carrier Proteins; Child, Preschool; Enzyme-Linked Immunosorbent Assay; Erythrocytes; Flow Cytometry; Humans; Infant; Malaria, Falciparum; Mice; Mice, Inbred BALB C; Middle Aged; Molecular Sequence Data; Peptides; Plasmodium falciparum; Protozoan Proteins; Protozoan Vaccines; Vaccines, Conjugate
ID: 205648