Figure 7.

Blood of MmuPV1 infected mice with skin tumours was infectious at seven months post initial IV injection. Each naïve littermate transfused by IV injection of 0.2 mL of blood (<1 × 10⁴ viral copies) from two infected mice sacrificed seven months after initial IV MmuPV1 infection was examined weekly for tumour growth at the pre-wounded skin area. (A, B) Representative tumour growth (arrows) at the muzzle and the tail of naïve Hsd: Nu female (A) and male (B) mice at week sixteen post blood transfusion. Viral DNA was detected at the vaginal (V), anal (A) and oral (O) sites in three females (C, F1-F3) and the penile (P), anal (A) and oral (O) sites in three male (D, M1-M3) mice by qPCR. Mucosal sites of these mice (the vagina, anus, tongue, and penile) were positive for viral DNA by in situ hybridization (F, arrows, 20×, in blue). These tissues were positive for viral E4 protein (G, 20×, in red). One of the females was positive for viral DNA (ISH arrows, 60×, in blue) and viral capsid protein L1 (IHC, arrows, 60×, in red) in the stomach tissues (E).