Recombinant CHIK virus E1 coat protein of 11 KDa with antigenic domains for the detection of Chikungunya

Chikungunya is an acute febrile illness caused by an alpha virus technically called as CHIK virus. A smaller size of CHIK virus E1 coat protein −11 kDa was expressed in prokaryotic expression system. The recombinant protein was purified and confirmed by western blot analysis. The positions of the antigenic domain in the protein were identified and the immunoreactivity of recombinant protein with anti-CHIK IgM antibodies was ascertained. The antigen showed an 88% sensitivity and 100% specificity by Indirect ELISA. No cross reactivity of the antigen was observed with anti-Dengue virus serum samples. The results strongly support that the recombinant CHIK coat protein could be used as a diagnostic antigen for the detection of Chikungunya by Indirect ELISA. The relevance of a smaller size recombinant antigen highlights its large scale application in serodiagnosis of CHIK virus since bacterial expression is more simple and cost effective than eukaryotic system.

► Antigenic domains were identified in the CHIK E1 coat gene sequence.
► Recombinant protein was produced by prokaryotic expression.
► Immunoreactivity of the recombinant antigen was confirmed by Indirect ELISA.
► Antigen showed 100% specificity and 88% sensitivity in detecting anti-CHIK IgM antibodies in patient serum samples.
► No cross reactivity was observed with other arboviral (Dengue) strains.