My professor said that in human body nearly 10$^9$-10$^1$$^2$ antibodies are produced by VDJ recombination and all the antigens that a person encounters in his lifetime are dealt by antibodies already present in his body. But he didn't explain what if the body in infected by a new mutated microbe(antigen) whose corresponding antibody is not present in the body.
My question is does our body have the mechanism to judge the epitope of the new antigen and synthesise an antibody with completely new paratope? If so what is it?
After reading the following I was forced to wonder whether the specificity of the antibodies improve(improve by synthesising new paratopes) after encountering antigens in the course of response.