Plasmodium vivax: immunological properties of tryptophan-rich antigens PvTRAg 35.2 and PvTRAg 80.6.
Need for malaria vaccine necessitates the characterization of potential antigens of the Plasmodium parasite. Recently, we have identified several Plasmodium vivax tryptophan-rich antigens (PvTRAgs). Here, we describe the immunological characterization of hitherto undescribed two such antigens PvTRAg 35.2 and PvTRAg 80.6 which are respective homologue of Plasmodium falciparum merozoite associated tryptophan-rich antigen (PfMaTrA) and P. falciparum tryptophan and threonine rich antigen (PfTryThrA) involved in erythrocyte invasion. Each of the pvtrag genes is comprised of two exons where exon 2 encodes for major part of the protein. PvTRAg 35.2 and PvTRAg 80.6 showed 97.06% and 94.12% (n = 34) seropositivity rates, and 92.3% (n = 13) and 100% (n = 29) lymphoproliferative responses, respectively, among P. vivax exposed individuals. Geometric mean values of IL-12, IFN-γ, TNF-α, IL-4 and IL-10 in PBMC culture supernatants of P. vivax exposed individuals were 182.02, 60.3, 62.84, 196.01 and 177.17 pg/ml against PvTRAg 35.2 and 185.27, 58.15, 64.56, 142.01 and 157.2 pg/ml against PvTRAg 80.6 showing mixed immune response with distinct biased towards anti-inflammatory Th2 phenotype. The pvtrag 35.2 gene was highly conserved in the parasite population whereas pvtrag 80.6 showed minor variations in the N-terminal region but highly conserved in the C-terminal region containing tryptophan-rich domain.
Mittra
Pooja
P
Department of Biotechnology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 11029, India.
Singh
Neeru
N
Sharma
Yagya D
YD
D000328:Adult; D000595:Amino Acid Sequence; D000913:Antibodies, Protozoan / Q000097:blood; D000953:Antigens, Protozoan / Q000235:genetics / Q000276:immunology*; D049109:Cell Proliferation; D017124:Conserved Sequence; D016207:Cytokines / Q000378:metabolism; D016054:DNA, Protozoan / Q000737:chemistry / Q000235:genetics; D005091:Exons; D005260:Female; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008297:Male; D008969:Molecular Sequence Data; D010963:Plasmodium falciparum / Q000235:genetics; D010966:Plasmodium vivax / Q000235:genetics / Q000276:immunology*; D015800:Protozoan Proteins / Q000235:genetics / Q000276:immunology; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D016207:Cytokines; D016054:DNA, Protozoan; D015800:Protozoan Proteins