Can anti-HLA antibodies change?
Yes and no. Once an antibody is made, it doesn’t really change. What changes are the types of antibodies that are made and the amount of these antibodies in the bloodstream. The immune system is very good at changing the antibodies that are made, to make the immune response even better. HLA antibody levels can be high following a transfusion or transplantation but significantly decrease in the months or years following. However, the cells that make antibodies can develop into memory cells and the antibody levels can go from undetectable to extremely high very quickly (within days) if a patient is exposed to a foreign HLA again.
