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.

Inclusion Criteria:

• Transplant recipients (lung or kidney) 18 years or older, more than 3 months after transplantation
• Transplant candidates (kidney) 18 years or older, to recieve influenza vaccination
• Healthy volunteers to receive influenza vaccination

Exclusion Criteria:

• Under 18 years of age
• Pregnant
• Medical contraindication for vaccine
• Transplant recipients receiving acute rejection therapy within one month
• Healthy volunteers with autoimmune disease or medications to mediate immune function
• Receipt of live, attenuated influenza vaccine, instead of injectable vaccine

Lung and kidney transplant recipients, patients with chronic kidney disease and healthy controls