Analysis of Fcgamma receptor IIa (cd32) gene polymorphism and anti-malarial IgG subclass antibodies to asexual blood-stage antigen of Plasmodium falciparum in an unstable malaria endemic area of Iran.

Sedigheh Zakeri (1) , Rahil Mashhadi (2) , Akram Abouie Mehrizi (1) , Navid Dinparast Djadid (1)

1 MVRG - Malaria and Vector Research Group
2 Biology department

One of the main host genetic factors involved in inflammation, immune responses and pathogenesis of malaria is FcγRIIa (cd32) gene. A single point mutation at position 131 replace an arginine (R) with a histidine (H) that can affect the affinity of the receptor for human IgG subclasses. This investigation was designed to explore the polymorphisms at FcγRIIa gene in association with both anti-malarial total IgG antibody and IgG subclass profiles to C-terminal region of Plasmodium falciparum merozoite surface protein 1 (PfMSP-1(19)). In this study, 166 infected patients with P. falciparum who are living in a malaria endemic area of Iran were studied using PCR-RFLP and ELISA methods. The results showed that the frequency of FcγRIIa-R/R131, -R/H131 and -H/H131 genotypes was 9.6%, 42.8% and 47.6%, respectively. Level of total IgG to recombinant PfMSP-1(19) antigen showed that there was no difference among the FcγRIIa-R/R131, -R/H131 and -H/H131 groups. With regards to the IgG subclasses, the anti-malarial IgG1 antibodies predominated. Also, there was a significant difference between the frequency of positive responders for anti-PfMSP-1(19) IgG and IgG1 antibodies in P. falciparum-infected individuals with FcγRIIa-R/R131, -R/H131 or -H/H131 genotypes (P<0.05, X(2) test). Regarding to IgG2-PfMSP-1(19) antibody, 27.27% (FcγRIIa-R/R131), 25.71% (FcγRIIa-R/H131) and 22.2% (FcγRIIa-H/H131) of IgG responders showed positive antibody response. Taken together, this study is the first report that exhibits the high frequency of both FcγRIIa-H131H genotypes and H131 allele in the Baluchi ethnic group, which was similar to the Fulani ethnic group. The present results provide additional data to understand the role of FcγRIIa-131 genotypes in the pathogenesis of malaria.

Mots clés: FccRIIa gene; Genotype; Mild malaria; Polymorphism; Antibody response; IgG subclasses

Domaines: Immunologie

Sedigheh Zakeri, Rahil Mashhadi, Akram Abouie Mehrizi, Navid Dinparast Djadid. Analysis of Fcgamma receptor IIa (cd32) gene polymorphism and anti-malarial IgG subclass antibodies to asexual blood-stage antigen of Plasmodium falciparum in an unstable malaria endemic area of Iran.. Experimental Parasitology, 2013, 134 (1), pp.115-21. ⟨10.1016/j.exppara.2013.02.012⟩. ⟨pasteur-00826154⟩