Diversity and expression of P. falciparum var gene in severe and mild malaria patients from Central India

Abstract Background PfEMP1 is encoded by a highly variable multicopy var gene family known to play key role in malaria pathogenicity. Therefore, we investigated sequence variation, expression profile and immune response of DBLα region of var gene. Methods Malaria (cerebral, severe and mild) samples were collected from highly endemic malaria region of Chhattisgarh, India. PCR amplicons were cloned and sequenced to determine the sequence variation. Expression level was analyzed targeting the upstream region of var gene using ddCT method. IgG level was determined against the six synthetic peptides of the DBLα region. Results The study identified that group1 and group 5 sequences (cys/PoLV classification) along with cys2/cys4 and MFK*/ REY motifs and short amino acid length were significantly associated with malaria severity.The specific PoLV (MFKS, LREA, PTNL) were restricted to cerebral malaria. Expressions level of var group A was higher than other var groups B and C, demonstrated its prognostic characteristic. All peptides showed high-quality IgG response, while VAR P5 appeared to be a good marker for severity. Conclusions Present study illustrated the presence of some specific sequence of DBLα tags involve in severe malaria and could be targeted for future interventions leading the malaria control and elimination.