The incidence of atherosclerotic complications is increased after kidney transplantation. Traditional risk factors do not fully explain this increased risk. Atherosclerosis is an inflammatory disease in which all players in the immune response are involved. The impact of these immune responses is not well known in immunocompromised patients, particularly among organ transplant. Nevertheless, the work of our group suggest that innate and acquired responses through different mechanisms influencing the evolution of atheromatous disease after transplantation.

The investigators therefore propose to study the impact of the expansion of regulatory T cells on the risk of atherosclerotic complications after transplantation.

Since November 2008, the investigators began a multicenter, prospective study whose purpose is to study in detail the immunological mechanisms of atherosclerosis after transplantation via immunomonitoring cohort of renal transplant patients in the Grand East Interregion. It was planned to include 500 patients and to date a little more than half have been included. After completion of the blood test, the tubes are routed over the Biomonitoring Platform (CIC-BT 506 Besançon) and the samples are stored in CRB Dijon.

The atherosclerotic events are recorded prospectively. The investigators hope to implement as part of ORLY IS, a second study to determine the impact of an expansion of regulatory T cells on the risk of atherosclerotic events.

Our hypothesis is that a cell rate regulatory T below the median results in an increase of 5% of atherosclerotic complications.

Inclusion Criteria:

1. Male or female patients aged over 18 years
2. Patients receiving a renal transplant
3. Patients able to understand the benefits and risks of testing
4. Patients gave written informed consent.

Exclusion Criteria:

1. Inability to understand the advantages and disadvantages of the study; psychiatric disorders judged by the investigator to be incompatible with the inclusion in the study.
2. Immunosuppressive therapy immediately prior to transplantation
3. Cancer (except skin cancer) or malignant blood disease being treated; active infection; decompensated cirrhosis [patients had cancer and considered as cured or in remission, patients with virus infection of hepatitis B or hepatitis C and having no cirrhosis may be included].

This study is strictly non-interventional, participation in another study is not a cons-indication to the inclusion in this study and no exclusion period is required for inclusion in another study after inclusion in this study (Art L. 1121-12 (loi n°2004-806 du 9 Août 2004).

The study population corresponds to 1000 patients receiving a renal transplant in Hospital of Besançon, Dijon, Nancy, Reims, Clermont-Ferrand, Strasbourg et Kremlin-Bicêtre.

Identified individual participant data for all outcome measures will be made available within 6 monts of study completion