Figure 5. Induction of mild lung injury renders adult sheep susceptible to JSRV infection.

(A) Schematic diagram of the study design. Ten adult sheep were randomly allocated in two groups. Sheep in Group I (red bar) were dosed 3MI (red arrow) as described in Materials and Methods while Group II served as control. After 2 days all animals in both groups were infected with JSRV (black arrow) and euthanized 10 days post infection. (B) Graph showing the mean number of JSRV Env⁺ clusters per animal as detected by immunohistochemistry in sheep of Group I and Group II 10 days post-infection (± SD). (C) Graph showing the number of cells forming each cluster of JSRV Env⁺ cells in sheep of Group I. (D–F) Immunohistochemistry of lung sections of adult sheep of group II (D) and group I (E–F, pre-treated with 3MI before JSRV infection) 10 days post-infection as described in Materials and Methods. Env expression (characterized by the intra cytoplasmic dark brown colour) was detected in sheep of Group I but not in sheep of Group II. Scale bars, D = 200 µm; E–F = 100 µm.