Anti-CMV Cellular Immunity Quantification Using an IGRA Test in Kidney Transplant récipients and Hemodialysis Patients, Comparison to Control Patients

Study Overview
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Brief Summary
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Evaluation of anti-CMV T cellular immunity using an IGRA test (Quantiferon-CMV test) in kidney transplant recipients and hemodialysis patients, comparison to control patients.

Detailed Description
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Cytomegalovirus (CMV) infection is a common opportunistic complication after kidney transplantation (KT). It has been associated with high morbidity and mortality in kidney transplant recipients (KTR). Its actual management is only based on the humoral immunity : the main risk factor for CMV infection after KT is the association of a seropositive donor and a seronegative recipient (so-called D+/R- mismatch). However several studies have highlighted the essential role of cellular immunity to control CMV infection. The Quantiferon-CMV (QF-CMV) is an IGRA test (Interferon Gamma Releasing Assay) which evaluates T CD8 lymphocytes production of Interferon Gamma (IFNy) exposed to CMV antigens. Some studies have shown the possible interest of the QF-CMV in predicting CMV infection after antiviral prophylaxis discontinuation or when CMV viremia is detected. However some limits have been underlined. First its positivity threshold hasn't been approved in KTR. Hemodialysis patients (HP) called to receive a renal allograft also suffered from altered immunity. No study has directly compared the QF-CMV value in KTR, HP and control patients. That's why we propose evaluating the expression of basal cellular immunity against CMV (far from any active infection) in KTR and HP using the QF-CMV and comparing it to control patients population (not suffering from kidney dysfunction or immunosuppression).

Official Title
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Quantification de l'immunité T Anti-CMV à l'Aide d'un Test IGRA Chez Des Patients greffés rénaux et Des Patients dialysés, Comparaison Avec Une Population de témoins

Conditions
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Quantiferon-CMV, Cytomegalovirus Infections, Kidney Transplant Infection, Hemodialysis

Intervention / Treatment
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* Diagnostic Test: Quantiferon CMV


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria : For all patients : to be seropositive for CMV to not be opposed to the study For kidney transplant recipients : to have received a kidney graft for over 1 year to have received an induction therapy at transplantation time by anti-lymphocytes antibodies and steroids to be currently receiving immunosuppressive therapy by calcineurins inhibitors (tacrolimus or cyclosporine), mycophenolic acid with or without steroids to not suffer from another cause of immunosuppression For hemodialysis patients : to be treated by hemodialysis for end stage renal disease without prior solid organ transplant history to not suffer from another cause of immunosuppression For control patients : with normal kidney function (estimated GFR > 90 ml/min) to not suffer from another cause of immunosuppression Exclusion Criteria : patient under guardianship or deprived of his liberty

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Group 1 : kidney transplant recipients (KTR)<br> | Diagnostic Test: Quantiferon CMV<br>* Evaluate and compare interferon gamma (IFNy) production by T CD8 cells exposed to CMV antigens in CMV seropositive kidney transplant recipients, hemodialysis and control patients<br>|
| Group 2 : hemodialysis patients<br> | Diagnostic Test: Quantiferon CMV<br>* Evaluate and compare interferon gamma (IFNy) production by T CD8 cells exposed to CMV antigens in CMV seropositive kidney transplant recipients, hemodialysis and control patients<br>|
| Group 3 : Control patients<br> | Diagnostic Test: Quantiferon CMV<br>* Evaluate and compare interferon gamma (IFNy) production by T CD8 cells exposed to CMV antigens in CMV seropositive kidney transplant recipients, hemodialysis and control patients<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Quantification of anti-CMV T cellular immunity in kidney transplant recipients, hemodialysis patients and control patients. | Quantification of IFNy level producted by T cells exposed to CMV antigens using a Quantiferon-CMV test in kidney transplant recipients, hemodialysis patients and control patients. | Single measurement at Day 0 of patient inclusion | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Quantification of patient cellular immunity. | Quantification of lymphocytes subpopulations. | Single measurement at Day 0 of patient inclusion | 
| Evaluation of kidney transplant recipient exposure to immunosuppressive therapy. | Assessment of last tacrolimus trough concentration. | Single collection at Day 0 of patient inclusion | 
| Estimation of renal function. | Evaluation of estimated glomerular filtration rate by plasmatic creatinin dosage using CKD-EPI estimate. | Single measurement at Day 0 of patient inclusion | 
| Assessment of CMV donor humoral immunity in kidney transplant recipients. | Assessment of donor CMV serology. | Single collection at Day 0 of patient inclusion |