Interest of Follicular Helper Lymphocytes / Regulatory Follicular Helper Lymphocytes Ratio in IgA Nephropathy

Study Overview
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Brief Summary
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This study aims to investigate the relevance of the Tfh/Tfr (Follicular helper T cells/ Follicular regulatory T cells) ratio in patients with IgA nephropathy: To identify a differential expression of the Tfh/Tfr ratio in patients considered stable or progressive To predict, at diagnosis, the clinical evolution of the disease (progressive or stable form) in the first year.

Official Title
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Interest of Follicular Helper Lymphocytes / Regulatory Follicular Helper Lymphocytes Ratio to Characterize and Predict Poor Prognosis Forms in IgA Nephropathy: an Exploratory Proof-of-concept Study

Conditions
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Glomerulonephritis, IGA

Intervention / Treatment
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* Other: Blood collection
* Other: Urine sample


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: IgA nephropathy histologically proven on renal biopsy according to KDIGO criteria, with 8 permeable glomeruli (patients diagnosed from 2009 with a minimum follow-up for their nephropathy of 5 years (arm 1) or patients diagnosed during the study (arm 2)) Control patients: Lupus or ANCA-associated vasculitis or polycystic kidney disease (arm 3) Exclusion Criteria: Legal incapacity or limited legal capacity Subjects with no social security coverage. Pregnancy / No effective contraceptive method

Ages Eligible for Study
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Minimum Age: 18 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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Design Details

Primary Purpose: Basic Science
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: IgA nephropathy in follow-up (arm 1)<br>Diagnosis of IgA nephropathy from 2009, with a minimum follow-up for nephropathy of 5 years | Other: Blood collection<br>* Collection of 3 blood tubes at inclusion and relapse (arm 1) or at inclusion, initiation of treatment and at 3 and 6 months post-diagnosis (arm 2)<br>Other: Urine sample<br>* Collection of 20 cc of urine at inclusion and relapse (arm 1) or at inclusion, initiation of treatment and at 3 and 6 months post-diagnosis (arm 2) or at inclusion only (arm 3)<br>|
| Other: Newly diagnosed IgA nephropathy (arm 2)<br>Diagnosis of IgA nephropathy during the study period | Other: Blood collection<br>* Collection of 3 blood tubes at inclusion and relapse (arm 1) or at inclusion, initiation of treatment and at 3 and 6 months post-diagnosis (arm 2)<br>Other: Urine sample<br>* Collection of 20 cc of urine at inclusion and relapse (arm 1) or at inclusion, initiation of treatment and at 3 and 6 months post-diagnosis (arm 2) or at inclusion only (arm 3)<br>|
| Other: CD163s control (arm 3)<br>Diagnosis of Lupus or ANCA-associated vasculitis or polycystic kidney disease | Other: Urine sample<br>* Collection of 20 cc of urine at inclusion and relapse (arm 1) or at inclusion, initiation of treatment and at 3 and 6 months post-diagnosis (arm 2) or at inclusion only (arm 3)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Form of IgA nephropathy exhibited by the patient (progressive or stable) | Patient with a diagnosis before the start of the study: IgA nephropathy with a GFR of less than 45 ml/min/1.73 m2 and/or proteinuria >0.5 g/day and/or hematuria (microscopic or macroscopic) will be considered progressive. Patient with diagnosis during the study: will be considered as progressive an IgA nephropathy for which the GFR will decrease compared to the inclusion (diagnosis) of more than 5 ml/min/1.73 m2 and/or with a proteinuria >0.5 g/day and/or with a microscopic hematuria on at least one of the samples carried out in a period of one year after the diagnosis. | 12 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Follicular helper T cells, Follicular regulatory T cells