Considering how often they'll be glued to the bacteria they're fighting, sounds fine to me.
I'm not even sure that they're recognized by the immune system as a threat. They won't be causing any infections that would trigger a response.
Response is triggered by any foreign protein.
It does not matter it is not infecting your cells. Anything that is not known to be you is attacked. And the more and longer you have of it inside of you, the bigger the immune response gets.