A study of the genomic diversity of Plasmodium falciparum in Senegal 1. Typing by southern blot analysis

Mercereau‐Puijalon, Odile; Jacquemot, Catherine; Sarthou, Jean-Louis

doi:10.1016/0001-706x(91)90079-y

Cited by 7 publications

(6 citation statements)

References 45 publications

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“…This was confirmed by DNA fingerprinting using the highly repetitive probe pPFrep20 (34) ( Fig. 3 B), previously shown to be highly sensitive in detecting genomic diversity (15,(30)(31)(32), as well as using the telomer-spedfic repeats (35) (Fig. 3 C) and Pf60.1, a repetitive probe recently isolated in our laboratory (15a) ( Fig.…”

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confidence: 71%

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Immune pressure selects for Plasmodium falciparum parasites presenting distinct red blood cell surface antigens and inducing strain-specific protection in Saimiri sciureus monkeys.

Fandeur

Scanf

Bonnemains

et al. 1995

The Journal of Experimental Medicine

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SummaryThe passive transfer of specific antibodies to a naive splenectomized Saimiri sciureus monkey infected with the Palo Alto FUP/SP strain of Plasmodiumfakiparum resulted in the emergence of parasites resistant to the transferred antibodies. Molecular typing indicated that the original and resistant parasites were isogenic. Saimiri monkeys primed with original parasites were fully susceptible to a challenge by the resistant ones, and vice versa. This absence of crossprotection indicates that strain-specific determinants would be the major targets of protective immunity developed in these monkeys. Phenotypic analysis showed that the surface of the infected red blood cells differed in both lines. Original parasites formed rosettes, autoagglutinated, presented characteristic knobs at the surface of the infected red blood cell, and did not agglutinate in the presence of a pool of human immune sera. In contrast, the resistant parasites did not form rosettes, did not spontaneously autoagglutinate, presented abnormal flattened knobs, and formed large aggregates in the presence of a pool of human immune sera. The presence of strain-specific determinants at the surface of the resistant parasites was confirmed by surface immunofluorescence and agglutination using homologous Saimiri serum. Neither the original nor the resistant parasites cytoadhered to an amelanotic melanoma cell line, suggesting that cytoadherence and agglutination can be dissociated. These results indicate that parasites that differ by the antigens exposed at the surface of the red blood cell induce strain-specific immunity. Furthermore they show that rosetting and nonrosetting parasites differ in their antigenic properties and do not crossprotect.

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confidence: 71%

“…Strain-speciflc Protection in Plasmodium fakiparum Malaria Molecular Typing of Parasites. In P. fakiparum parasites, the strain-specific genetic background is readily visualized using repetitive probes (15,(30)(31)(32). Fig.…”

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confidence: 99%

Immune pressure selects for Plasmodium falciparum parasites presenting distinct red blood cell surface antigens and inducing strain-specific protection in Saimiri sciureus monkeys.

Fandeur

Scanf

Bonnemains

et al. 1995

The Journal of Experimental Medicine

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“…In addition, the DNA fragments of 11 parasite clones/strains (3D7AH1, NF54, FCR3S1.2, TM284S2, Dd2, FCB-3, K1, R29, FCR3CSA, F32 and UAS22) encoded by exon I of the molecule were sequenced and only four point mutations were found (in K1, 3D7AH1 and Dd2; Table 1). In contrast, sequence polymorphism was mainly reported in the repetitive region of exon II [14], as often seen in molecules important during sporozoite and merozoite invasion such as the repetitive regions of the circumsporozoite protein (CSP) and the block two sequence of MSP-1.…”

Section: Resultsmentioning

confidence: 99%

“…Molecules that participate in this interaction between iRBC and RBC may likewise play an important role in the initial adhesion process between merozoite and RBC [9]. A candidate molecule mediating the interaction between late stage iRBC and RBC is the polypeptide Pf332 (Antigen 332), which was first identified by Mercereau-Puijalon [13], [14]. Pf332 is highly glutamic acid rich and contains long repetitive sequences in an internal region named EB200, and a conserved tryptophan-rich domain (WRD) with similarities to that of PfEMP-1, SURFIN, and PkSICAvar [4].…”

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confidence: 99%

A Novel DBL-Domain of the P. falciparum 332 Molecule Possibly Involved in Erythrocyte Adhesion

et al. 2007

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Plasmodium falciparum malaria is brought about by the asexual stages of the parasite residing in human red blood cells (RBC). Contact between the erythrocyte surface and the merozoite is the first step for successful invasion and proliferation of the parasite. A number of different pathways utilised by the parasite to adhere and invade the host RBC have been characterized, but the complete biology of this process remains elusive. We here report the identification of an open reading frame (ORF) representing a hitherto unknown second exon of the Pf332 gene that encodes a cysteine-rich polypeptide with a high degree of similarity to the Duffy-binding-like (DBL) domain of the erythrocyte-binding-ligand (EBL) family. The sequence of this DBL-domain is conserved and expressed in all parasite clones/strains investigated. In addition, the expression level of Pf332 correlates with proliferation efficiency of the parasites in vitro. Antibodies raised against the DBL-domain are able to reduce the invasion efficiency of different parasite clones/strains. Analysis of the DBL-domain revealed its ability to bind to uninfected human RBC, and moreover demonstrated association with the iRBC surface. Thus, Pf332 is a molecule with a potential role to support merozoite invasion. Due to the high level of conservation in sequence, the novel DBL-domain of Pf332 is of possible importance for development of novel anti-malaria drugs and vaccines.

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“…Breaking and healing of genes occurring in subtelomeric regions are known to influence the gene variation [39]. However, so far it appears as if the degenerate repeats of Pf332 are expressed in all parasites isolates analysed [40,41] and that the expression is stable when parasites are passaged in monkeys [42].…”

Section: Discussionmentioning

confidence: 99%

Antibody responses to the repetitivePlasmodium falciparumantigen Pf332 in humans naturally primed to the parasite

Ahlborg

Haddad

Siddique

et al. 2002

Clinical and Experimental Immunology

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SUMMARYAntibodies to the degenerate repeats of EB200, a part of the Plasmodium falciparum antigen Pf332, are protective in monkeys. To analyse the prevalence, magnitude and specificity of antibodies to EB200 in malaria-exposed humans, the IgG antibody reactivity with recombinant EB200 protein as well as with crude malaria antigen was determined in Senegalese donors (n = 100; 4-87 years). Antibody reactivity with EB200 was low or absent in children below 15 years but was prevalent and significantly higher in older donors. In comparison, all individuals displayed reactivity with a crude malaria antigen preparation, which also increased with age. The reactivity with the crude malaria antigen was correlated to the reactivity with EB200, suggesting that the low levels of IgG to EB200 found in some adult donors reflected a limited degree of recent exposure to parasites rather than a selective nonresponsiveness to Pf332. Comparison of serological and clinical data showed that high levels of antibodies to crude malaria antigen and to EB200 were predictive of fewer future clinical attacks of malaria. A reactivity pattern very similar to that found in Senegalese donors was observed in Liberian adults where 80% of the sera showed reactivity with EB200 and all peptides were recognized by between 60 and 100% of the donors. This strong reactivity with EB200-derived overlapping peptides suggests that the epitopes in EB200, to a large extent, are linear. In the light of previous data on the parasite neutralizing capacity of antibodies to Pf332, the present results emphasize the potential interest of Pf332-derived sequences for inclusion in a subunit vaccine against P. falciparum malaria.

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A study of the genomic diversity of Plasmodium falciparum in Senegal 1. Typing by southern blot analysis

Cited by 7 publications

References 45 publications

Immune pressure selects for Plasmodium falciparum parasites presenting distinct red blood cell surface antigens and inducing strain-specific protection in Saimiri sciureus monkeys.

Immune pressure selects for Plasmodium falciparum parasites presenting distinct red blood cell surface antigens and inducing strain-specific protection in Saimiri sciureus monkeys.

A Novel DBL-Domain of the P. falciparum 332 Molecule Possibly Involved in Erythrocyte Adhesion

Antibody responses to the repetitivePlasmodium falciparumantigen Pf332 in humans naturally primed to the parasite

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