The purpose of this study is to evaluate the immune response to a routine influenza vaccination. Influenza vaccination is given as part of routine standard of care in these individuals and is not part of the study protocol. The study will evaluate for a change in response to common antigens over time after influenza vaccination to determine if changes are related to the development of chronic rejection after solid-organ transplantation. We hypothesize that the influenza vaccine contributes to the alloreactivity of T cells verses common HLA types in the donor pool.