title: Peptides of the liver stage antigen-1 (LSA-1) of Plasmodium falciparum bind to human hepatocytes.
abstract: Synthetic peptides from the liver stage antigen-1 (LSA-1) antigen sequence were used in HepG2 cell and erythrocyte binding assays to identify regions that could be involved in parasite invasion. LSA-1 protein peptides 20630 ((21)INGKIIKNSEKDEIIKSNLRY(40)), 20637 ((157)KEKLQGQQSDSEQERRAY(173)), 20638 ((174)KEKLQEQQSDLEQERLAY(190)) and 20639 (191KEKLQEQQSDLEQERRAY(207)) had high binding activity in HepG2 assays. Were located in immunogenic regions; peptide cell binding was saturable. Peptide 20630 bound specifically to 48kDa HepG2 membrane surface protein. LSA-1 peptides 20630 ((21)INGKIIKNSEKDEIIKSNLRY(40)) and 20633 ((81)DKELTMSNVKNVSQTNFKSLY(100)) showed specific erythrocyte binding activity and inhibited merozoite invasion of erythrocytes in vitro. A monkey serum prepared against LSA-1 20630 peptide analog (CGINGKNIKNAEKPMIIKSNLRGC) inhibited merozoite invasion in vitro. The data suggest LSA-1 "High Activity Binding Peptides" could play a possible role in hepatic cell invasion as well as merozoite invasion of erythrocytes.
authors.affiliation: Fundación Instituto de Inmunologi;a de Colombia, Universidad Nacional de Colombia, Bogotá, Colombia.
authors.forename: Javier E
authors.initials: JE
authors.lastname: García
authors.forename: Alvaro
authors.initials: A
authors.lastname: Puentes
authors.forename: Ramsés
authors.initials: R
authors.lastname: López
authors.forename: Ricardo
authors.initials: R
authors.lastname: Vera
authors.forename: Jorge
authors.initials: J
authors.lastname: Suárez
authors.forename: Luis
authors.initials: L
authors.lastname: Rodríguez
authors.forename: Hernando
authors.initials: H
authors.lastname: Curtidor
authors.forename: Marisol
authors.initials: M
authors.lastname: Ocampo
authors.forename: Diana
authors.initials: D
authors.lastname: Tovar
authors.forename: Martha
authors.initials: M
authors.lastname: Forero
authors.forename: Adriana
authors.initials: A
authors.lastname: Bermudez
authors.forename: Jimena
authors.initials: J
authors.lastname: Cortés
authors.forename: Mauricio
authors.initials: M
authors.lastname: Urquiza
authors.forename: Manuel E
authors.initials: ME
authors.lastname: Patarroyo
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000953:Antigens, Protozoan / Q000737:chemistry* / Q000378:metabolism*; D045744:Cell Line, Tumor; D022781:Hepatocytes / Q000378:metabolism / Q000469:parasitology*; D006801:Humans; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D010963:Plasmodium falciparum / Q000737:chemistry / Q000254:growth & development / Q000276:immunology* / Q000378:metabolism
chemical_list: D000953:Antigens, Protozoan; D010455:Peptides; C067302:liver stage-specific antigen, Plasmodium