FIGURE 4.

Superinfection-based minigenome and iVLP assays. BHK-21 cells were transfected with the indicated control or minigenome plasmids based on L, M, or S segments of SFTSV or HRTV, together with pRL-TK. Twelve hours post-transfection, cells were respectively superinfected with SFTSV or HRTV (MOI = 3). Forty-eight hours post-superinfection, cells were delivered to luc activity measurements and the relative luc activities (Rel. Luc. Act.) were shown in (A). See also Table 1. Meanwhile, supernatants of the superinfected BHK-21 cell cultures were collected and used to infect fresh HEK293T cells, followed by firefly luc activity (Luc. Act.) detection at 48 hpi (B). Data are presented as mean ± SEM, n = 3.