Characterization of the 175-kilodalton erythrocyte binding antigen of Plasmodium falciparum.
Mol Biochem Parasitol
; 40(2): 285-94, 1990 May.
Article
en En
| MEDLINE
| ID: mdl-2194125
ABSTRACT
EBA-175 is a soluble 175-kDa Plasmodium falciparum antigen that is released into culture supernatants during rupture of schizont-infected erythrocytes. EBA-175 binds to erythrocytes and binding is sialic acid-dependent. A clone expressing the gene encoding EBA-175 was obtained previously by screening a genomic DNA expression library with antibodies that had been affinity-purified from EBA-175. Antibodies were raised against a 43-amino-acid peptide (EBA-peptide 4) synthesized according to the deduced amino acid sequence. Antibodies to peptide 4 and affinity-purified antibodies specific for EBA-175 were used to characterize further EBA-175 giving the following results:
(1) EBA-175 differs biochemically and immunologically from other reported malarial antigens; (2) the EBA-175s from six geographical isolates of P. falciparum are antigenically conserved; (3) EBA-175 is expressed during schizogony as a 190-kDa protein which is larger than the culture supernatant form of the antigen. The 190-kDa form of the protein is recovered from the cell pellet in schizont-infected erythrocytes and partitions to the soluble fraction when extracted with detergent; (4) release of soluble EBA-175 into the culture supernatant coincides with schizont rupture; (5) there was no observable change in pI (pI = 6.86) by isoelectric focusing between the cellular and supernatant species of the protein; and (6) release of EBA-175 into the culture supernatant is inhibited by the addition of chymostatin and leupeptin. The continued research into the role of EBA-175 during erythrocyte invasion may aid in vaccine development for malaria.
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Banco de datos:
MEDLINE
Asunto principal:
Plasmodium falciparum
/
Proteínas Protozoarias
/
Eritrocitos
/
Antígenos de Protozoos
Límite:
Animals
/
Humans
Idioma:
En
Año:
1990
Tipo del documento:
Article