FIG 7.

Stability of ΔC-CHIKV in cell culture. (A) Detection of viral genome stability during passage by RT-PCR. Viral RNAs were extracted from infected cells or supernatants as described in Materials and Methods. RT-PCR was performed with a pair of primers spanning the nsP4-E3 region. (B) Plaque morphology comparison between P0 and P5 ΔC-CHIKV. (C) Comparison of growth kinetics of P0 and P5 ΔC-CHIKV mutants. Viral growth curves were conducted at an MOI of 0.01. Three independent experiments were performed in duplicate, and representative data are presented. (D) IFA of expression of different viral proteins in P0 and P5 ΔC-CHIKV using polyclonal antibodies against E2 and capsid. (E) Sequence chromatograms of all three passaged viruses (P5-A, P5-B, and P5-C). The initial amino acids of the E3 gene are indicated.