Fig. 6.

In vivo PTTG1IP-EV-mediated delivery of Cre recombinase.

(A) Timeline of EV-transfer experiment to Cre reporter mice. 24 h after donor cell transfection with Cre constructs and VSVG, media was replaced with fresh Opti-MEM and EVs are isolated 48 h later by SEC. 10 days before EV transfer, mice were injected with 500,000 B16F10 Cre reporter cells/mouse. On day 10, isolated EVs were injected to recipient mice by intratumoral injection (1 × 10¹⁰ EVs/mice). 4 days later, tumors were harvested and Cre activity analysed. (B) Cre recombination activity in mouse tumors treated with PTTG1IP-intein-Cre + VSVG, Cre + VSVG or VSVG only (control EVs). Cre recombination site was amplified by PCR and the products resolved by agarose gel electrophoresis. Cre recombination is indicated by a shorter 900 bp product (arrow) while non-recombined site is observed as a 1,700 bp product. Recombination percentages are indicated for each sample. (C) GFP expression in mouse tumors treated with PTTG1IP-intein-Cre + VSVG EVs, Cre + VSVG EVs or PBS analysed by immunohistochemistry. n = 3 mice. Scale bar represents 150 μm.