Peptides of the liver stage antigen-1 (LSA-1) of Plasmodium falciparum bind to human hepatocytes.
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.
García
Javier E
JE
Fundación Instituto de Inmunologi;a de Colombia, Universidad Nacional de Colombia, Bogotá, Colombia.
Puentes
Alvaro
A
López
Ramsés
R
Vera
Ricardo
R
Suárez
Jorge
J
Rodríguez
Luis
L
Curtidor
Hernando
H
Ocampo
Marisol
M
Tovar
Diana
D
Forero
Martha
M
Bermudez
Adriana
A
Cortés
Jimena
J
Urquiza
Mauricio
M
Patarroyo
Manuel E
ME
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
D000953:Antigens, Protozoan; D010455:Peptides; C067302:liver stage-specific antigen, Plasmodium