IgG subclasses pattern and high-avidity antibody to the C-terminal region of merozoite surface protein 1 of Plasmodium vivax in an unstable hypoendemic region in Iran.

Akram Abouie Mehrizi (1, 2) , Sedigheh Zakeri (1) , Ali-Hatef Salmanian (2) , Mohammad Hossein Sanati (2) , Navid Dinparast Djadid (1)

1 MVRG - Malaria and Vector Research Group
2 National Research Center for Genetic Engineering and Biotechnology

The C-terminal region of Plasmodium vivax merozoite surface protein 1 (PvMSP-1(19)) is a leading vaccine candidate for inclusion in a polyvalent malaria vaccine. In the present study, the IgG subclasses profile and the avidity of IgG to PvMSP-1(19) were evaluated in individuals (n=94) naturally exposed to P. vivax parasite in malaria endemic areas in Chabahar districts, Iran. In individuals with patent P. vivax malaria, 86.1% was sero-positive to PvMSP-1(19) and IgG1 (81.9%) was the predominant subclass. In addition, to determine the persistence of specific IgG, IgG1 and IgG3 antibodies to PvMSP-1(19), the frequency of antibodies was determined in the infected subjects (n=74) after treatment with standard chloroquine and it was detected that the frequency of responders was significantly reduced to 51.3%, 51% and 16.2%, respectively. The antigen-binding avidity of IgG antibodies to PvMSP-1(19) was measured in sero-positive sera and the high-avidity of IgG, IgG1 and IgG3 was found in 66.6%, 61% and 47% of the infected subjects with P. vivax, respectively. The present result shows that individuals who exposed to vivax malaria in the endemic region in Iran develop antibodies with high-avidity to PvMSP-1(19). These results could help to understand the interactions between the host and P. vivax parasite in development of MSP-1(19)-based vaccine.

Mots clés: Malaria; Plasmodium vivax; C-terminal region of MSP-1; Antibody; Avidity; Immune response

Domaines: Génétique

Akram Abouie Mehrizi, Sedigheh Zakeri, Ali-Hatef Salmanian, Mohammad Hossein Sanati, Navid Dinparast Djadid. IgG subclasses pattern and high-avidity antibody to the C-terminal region of merozoite surface protein 1 of Plasmodium vivax in an unstable hypoendemic region in Iran.. Acta Tropica, 2009, 112 (1), pp.1-7. ⟨10.1016/j.actatropica.2009.05.016⟩. ⟨pasteur-00751818⟩