I am under the impression that since your immune systeme will be set to 'blank', then yes, if you care to, or need to, you would have to have all of your vaccines re-done.
I work in health care, and will not be able to return to work in a hospital without being able to be tested for and hae measurable titers for past vaccinations. Then, I would have to have the ones required for working in a hospital like TB, and Hep c among others.
I would not want to blast my immune system with all of that stuff too quickly, so if the immune ablation results in a return to health, I will likely not go back to working in healthcare.
Then, of course, think about all of the coughs and colds you've had in your lifetime that you are immune to before the ablation...