Patients undergoing renal transplantation at London Health Sciences Centre, University Hospital and who are participating in the study "A Comparison of Effects of Standard Dose vs Low Dose Advagraf with IL-2 Receptor Antibody Induction, MMF and Steroids, With or Without ACEi/ARB-based Antihypertensive Therapy on Renal Allograft Histology, Function, and Immune Response" will be evaluated with the ImmuKnow Assay to assess the ability of this assay to predict underimmunosuppression (rejection) or overimmunosuppression determined by this test and to determine retrospectively whether decision making utilizing this novel assay would have improved outcomes over standard techniques.

This study is designed to evaluate an in vitro assay (Cylex®ImmuKnow Assay) for the measurement of cell-mediated immune response in renal transplant patients receiving immunosuppressive therapy. This assay measures ATP as an activation response of CD4+ cells to stimulation with phytohemagglutinin (PHA) in whole blood samples as a reflection of the immune system of the patient at any point in therapy. The natural history of the immune status of the renal transplant recipient as reflected by the ImmuKnow assay will be determined at specific time points of interest including: pre and post transplant, as an adjunct to therapeutic drug monitoring, and pre and post infectious or rejection episode. Analysis of the results of the assay at these time points will allow us to retrospectively study the effects of routine immunosuppressive agent modulation on immune function, and its subsequent effects in times of renal allograft insult.

Inclusion Criteria:

• Patients undergoing implantation surgery for renal transplantation at London Health Sciences Centre, University Hospital
• Patients who have consented to the study entitled, "A Comparison of Effects of Standard Dose vs Low Dose Advagraf with IL-2 Receptor Antibody Induction, MMF and Steroids, With or Without ACEi/ARB-based Antihypertensive Therapy on Renal Allograft Histology, Function, and Immune Response" Exclusion Criteria:

Exclusion Criteria:

• None

All participants enrolled in this study will be undergoing renal transplantation and will have already been consented to the study entitled, "A Comparison of Effects of Standard Dose vs Low Dose Advagraf with IL-2 Receptor Antibody Induction, MMF and Steroids, With or Without ACEi/ARB-based Antihypertensive Therapy on Renal Allograft Histology, Function, and Immune Response."