It appears to me as if some of the Hachibi's chakra has been imbued into Sasuke.

Naruto 413 page 10-11 | One Manga

It is here Sasuke was hit. During that hit, it may have been possible that some bijuu chakra was passed onto Sasuke. ^_^

Next we are shown that Juugo is trying to heal Sasuke since he has the curse seal, and he says they should be compatible enough to heal him.

Naruto 413 page 14 | One Manga

Is it there that Juugo unknowingly seals the Bijuu chakra into Sasuke? But now, Sasuke doesn't have the curse seal, so if this is a little part of Hachibi inside of him, no one will be able to stop him, or heal him from the damage the 8-tails power will bring.

Naruto 460 page 14 | One Manga

What do you think?