3.2∣Epicutaneous DNA vaccine ameliorated For t 2-induced scratch behaviors in mice
To evaluate the therapeutic effect of For t 2 DNA patch vaccine, all mice were sensitized intra-peritoneally (IP) with E. coli -expressed recombinant For t 2/alum according to a previously published model. Then, on days 14, 21, and 28, mice received the For t 2 DNA patch onto the pre-shaved skin at doses of 10, 25, and 50 μg (SV10, SV25 and SV50) for 1 hour. After the final challenge, the scratching behaviors (surrogate marker of an itch) were immediately videotaped for 1 hour. In the non-vaccinated group, the mean number of scratching bouts was >300 (Figure S4). All For t 2 DNA patch-treated groups showed significantly fewer scratching bouts compared with the non-vaccinated group.