This site needs JavaScript to work properly. Please enable it to take advantage of the complete set of features!
Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

NIH NLM Logo
Log in
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
doi: 10.1186/1475-2875-6-95.

Polymorphism and epitope sharing between the alleles of merozoite surface protein-1 of Plasmodium falciparum among Indian isolates

Affiliations

Polymorphism and epitope sharing between the alleles of merozoite surface protein-1 of Plasmodium falciparum among Indian isolates

Anitha Mamillapalli et al. Malar J. .

Abstract

Background: The C-terminal region of merozoite surface protein-1 (MSP-1) is one of the leading candidates for vaccination against the erythrocytic stages of malaria. However, a major concern in the development of MSP-1 based malaria vaccine is the polymorphism observed in different geographical Plasmodium falciparum isolates. To explore whether the sequence heterogeneity of PfMSP-1 leads to variation in naturally acquired anti-MSP-119 antibodies, the present study was undertaken to study PfMSP-119 sequence polymorphism in malaria-endemic villages in eastern India and also carried out a competition enzyme-linked immunosorbent assay using three PfMSP-119 variant forms.

Methods: The sequence variations in the C-terminal region of PfMSP-119 were determined in a malaria endemic region. Three PfMSP-119 variants were produced in Escherichia coli (PfMSP119QKNG-L, PfMSP119EKNG-L and PfMSP119ETSR-F) and an immunodepletion assay was carried out using the corresponding patients' sera.

Results: Results revealed predominance of PfMAD20 allele among Indian field isolates. Seven PfMSP-119 variant forms were isolated in a singe geographical location. Three of PfMSP-119 variant forms when expressed in E. coli showed presence of cross-reaction as well as variant specific antibodies in malaria infected patient sera.

Conclusion: The present study demonstrates the existence of allele specific antibodies in P. falciparum-infected patient sera, however their role in protection requires further investigation. These results thereby, suggest the importance of a multi-allelic PfMSP-119 based vaccine for an effective malaria control.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Sequence diversity in the C-terminal region (blocks 16 and 17) of MSP-1 in Indian P. falciparum isolates in a single geographical location.
Figure 2
Figure 2
Expression and immunoblot analysis of E. coli expressed PfMSP-119 variants. (a) Coomassie blue-stained 12% SDS-polyacrylamide gel of purified PfMSP-119 variants. (b & c) Immunoblot analysis to show the reactivity of PfMSP-119 variants with monoclonal antibodies (12.10) and with anti-PfMSP119 (Q-KNG-L) antibody.
Figure 3
Figure 3
Reactivity of PfMSP-119 variants in an ELISA with sera collected from P. falciparum infected patients at a dilution of 1:200. Error bars indicate S.D.
Figure 4
Figure 4
Immunodepletion assay showing the presence of PfMSP119 allele specific antibodies in sera from P. falciparum infected patients. Error bars indicate S.D.

References

    1. Richie TL, Saul A. Progress and challenges for malaria vaccines. Nature. 2002;415:694–701. doi: 10.1038/415694a. - DOI - PubMed
    1. Sachs J, Malaney P. The economic and social burden of malaria. Nature. 2002;415:680–685. doi: 10.1038/415680a. - DOI - PubMed
    1. Good MF. Towards a blood-stage vaccine for malaria: are we following all the leads? Nat Rev Immunol. 2001;1:117–125. doi: 10.1038/35100540. - DOI - PubMed
    1. Blackman MJ, Holder AA. Secondary processing of the Plasmodium falciparum merozoite surface protein-1 (MSP1) by a calcium-dependent membrane-bound serine protease shedding of MSP133 as a noncovalently associated complex with other fragments of the MSP1. Mol Biochem Parasitol. 1992;50:307–315. doi: 10.1016/0166-6851(92)90228-C. - DOI - PubMed
    1. Cooper JA. Merozoite surface antigen-1 of Plasmodium. Parasitol Today. 1993;9:50–54. doi: 10.1016/0169-4758(93)90031-A. - DOI - PubMed

Publication types

MeSH terms

Full text links
BioMed Central full text link BioMed Central Free PMC article
Cite

AltStyle によって変換されたページ (->オリジナル) /