Figure 2.

(A,B) Propagation of Ank-2 strain of Crimean Congo hemorrhagic fever virus (CCHFV) in Scott and White No. 13 (SW-13) cells on day five (A: cell control, B: virus infected cells). Magnification ×400. (C) Plasmid construct used for DNA immunization in this study. In vitro homologous recombination between the empty vector and amplified nucleocapsid, flanked by 50 bp homologous arms to the EcoRI recognition sequence of the vector multiple cloning site, occurs in the presence of the Seamless Ligation Cloning Extract (SLiCE) lysate from PPY bacteria, adenosine triphosphate (ATP), 1,4-Dithiothreitol (DTT), and MgCl₂ at 37 °C. (D–G) N protein expression in the cells transfected by pV-N13 via indirect immunofluorescence assay (IIFA) 72 hours post DNA delivery (D: phase contrast; E: fluorescent contrast). CD24 protein expression in the cells transfected by pCD24 via IIFA after 72 h (F: phase contrast; G: fluorescent contrast). (H) Western blot analysis of the BHK21-C13 cells transfected with pV-N13. The expected protein (~52 kDa) was detected after 72 h (lane 1). We included pVAX-1 transfected cells (lane 2) and cell control (lane 3) in the assay.