Our immune systems function at all levels. Some just have stronger ones than others. Not all of us respond in a similar way to vaccines.
The comments on the workings of the immune systems of those who showed no response were speculative and it was made clear, that no response to the vaccine did not mean poor take up, just the possibility that for some people that may be the reason.
I have never had any adverse reactions to a vaccination, that I can remember, but I do overreact to oral medication and I am allergic to penicillin. The immune sytem is a complex system.