T-SPOT.CMV and T-SPOT.PRT Diagnostic Assays

Inclusion criteria: 1. Active candidate or recipient of a kidney transplant. Patients enrolled post-transplant must be within 6 months of transplantation and on active CMV anti-viral prophylaxis. 2. Age ≥ 18 years. 3. CMV serology of donor and recipient confirmed prior to enrollment. For seronegative subjects (R-), CMV serostatus should be confirmed within eight weeks prior to transplant by the site local laboratory. 4. Able to provide T-SPOT pre-transplant samples up to a maximum of one month prior to transplant (in the interval between Day -30 and Day 0), or at the time of enrollment if this occurs following transplantation. 5. IRB approved written Informed Consent and privacy language per national regulation (e.g., Health Insurance Portability and Accountability Act for US sites) must be obtained from the subject or legally authorized representative prior to any study related procedures, including screening evaluations and tests. Exclusion criteria: 1. Anemia prior to transplant that indicates not a candidate for blood draw. 2. On active immunosuppression within two months prior to transplant. 3. Multi-organ transplant (dual-kidney allocation is allowed). 4. Subject has received prior exposure to a CMV vaccine. 5. Subject has undergone or is planning to undergo plasmapheresis. 6. Subject requires desensitization for ABO blood type incompatibility or a positive T or B-cell crossmatch. 7. Subject is known to be HIV positive. 8. Subject is known to have a clinically significant medical or psychiatric condition considered a high risk for participation in an investigational study.