Study of the Role of Regulator T Cells in the Pathophysiology of Childhood Henoch Schönlein Purpura (FOX-TREG)

The primary objective of this study is to search for evidence of quantitative or functional defects in plasma regulatory T cells (Tregs) in pediatric patients with Henoch Schönlein Purpura (HSP) as compared to a control population.

Study Overview

• Status: Completed
• Conditions: Henoch Schönlein Purpura
• Intervention / Treatment: Biological: Blood samples; Biological: Stool samples

Detailed Description

The secondary questions/objectives for this study are:

A. During an inflammatory HSP flare, is there a quantitative and / or qualitative defect in plasma Tregs? Are such blood anomalies real or are they due to a modification of the distribution of theses cells to localized sites? B. In the asymptomatic phase, are there quantitative or functional abnormalities among Tregs in subjects with HSP compared to healthy control subjects? C. Are Treg abnormalities associated with modifications in other blood cell lineages, including B cells secreting IgA and abnormally glycosylated IgA1, and secretion of cytokines during acute relapses and during the asymptomatic phase? D. Can streptococcus or other oral or digestive pathogens (bacterial or viral) (as suggested in other chronic diseases such as rheumatoid arthritis ) provoke (via stimulation Th3) isotype commutation towards secretion of IgA1 at the origin of HSP? Does HSP intestinal damage or imbalance of the intestinal microbiota allow the translocation of intestinal microorganisms that sustain this stimulation?

• Study Type: Observational
• Enrollment (Actual): 100

Contacts and Locations

Study Locations

• France
  • Montpellier, France, 34295
    • CHRU de Montpellier - Hôpital Lapeyronie
  • Nîmes, France, 30029
    • CHRU de Nîmes - Hôpital Universitaire Carémeau

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 3 years to 17 years (Child)
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Three different populations will be included in this study: (A) patients presenting with an acute episode of Henoch Schönlein purpura; (B) patients who have had an episode of Henoch Schönlein purpura in the past, but currently present with no symptoms; (C) a group of control patients recruted from elective surgery candidates at the participating hospitals.

Description

General inclusion criteria for all sub-populations included in the study

• The child (with age- and comprehension-skill-appropriate information) and parents (or persons exercising parental authority) have been informed about the implementation of the study, its objectives, constraints and patient rights
• The child (depending on age) and parents (or persons exercising parental authority) have given their free and informed consent and signed the consent
• The patient must be insured or beneficiary of a health insurance plan

Inclusion criteria for population A: Henoch Schönlein purpura, acute episodes

• The diagnosis of Henoch Schönlein purpura was made by a physician according to the EULAR / PRES / PRINTO 2010 criteria (purpura predominantly on the lower limbs associated with one of the following criteria: abdominal pain, arthralgia or arthritis, kidney damage or suggestive histology (immune deposits dominated by Immunoglobulin A (IgA))
• The patient is not treated via immunosuppression (steroids or other immunosuppressive / biotherapy) and has not been treated like this for at least 15 days

Inclusion criteria for population B: Henoch Schönlein purpura in remission

• The diagnosis of Henoch Schönlein purpura was made by a physician according to the EULAR / PRES / PRINTO 2010 criteria
• The patient has has a Henoch Schönlein purpura episode in the past, and no longer has any symptoms of the disease
• The patient is not treated via immunosuppression (steroids or other immunosuppressive / biotherapy) and has not been treated like this for at least 15 days

Inclusion criteria for population C: controls

• Subjects free from infectious, inflammatory or autoimmune diseases
• Candidates for elective surgery (circumcision, urological surgery, removal of tonsils and adenoids)

Exclusion Criteria:

• The patient is participating in another interventional study or is in an exclusion period determined by a previous study
• The child refuses to participate in the study
• Parents (or persons with parental responsibility if any) refuse to sign the consent
• It is impossible to correctly inform the patient or his/her parents (or persons with parental authority if any)
• The patient has another inflammatory or autoimmune disease
• Patient on immunosuppressive / biotherapy treatments

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Control
• Time Perspectives: Cross-Sectional

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
HSP: acute episode; Patients in this group are going through an acute episode of Henoch Schönlein Purpura. Intervention: Blood samples Intervention: Stool samples	Biological: Blood samples; Compared to routine practice, 3 additional tubes of blood will be drawn for the observational needs of this study.; Biological: Stool samples; Stool samples will be collected for the observational needs of this study (and are not part of routine practice).
HSP: remission; Patients in this group have had Henoch Schönlein Purpura in the past but currently have no symptoms. Intervention: Blood samples Intervention: Stool samples	Biological: Blood samples; Compared to routine practice, 3 additional tubes of blood will be drawn for the observational needs of this study.; Biological: Stool samples; Stool samples will be collected for the observational needs of this study (and are not part of routine practice).
Control group; Control patients recruited from elective surgery candidates at the participating hospitals. Intervention: Blood samples Intervention: Stool samples	Biological: Blood samples; Compared to routine practice, 3 additional tubes of blood will be drawn for the observational needs of this study.; Biological: Stool samples; Stool samples will be collected for the observational needs of this study (and are not part of routine practice).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percentage of blood Tregs		Day 0
Absolute Treg count	number / mm^3	Day 0
Presence / absence of functional abnormality of plasma Tregs		Day 0

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Numerical abnormalities in other blood cell lines		Day 0
Serum cytokine levels	ng/ml	Day 0
Serum IgA levels	mg/l	Day 0
Presence/absence of bacterial translocation		Day 0
Quantification of bacterial translocation	(10^8 copies / µl)	Day 0
Number of bacterial species detected in the intestinal microbiota		Day 0
Distribution of bacteria taxa present in the intestine among 3 categories	Bacteroidetes, Firmicutes and Actinobacteria	Day 0

Collaborators and Investigators

• Sponsor: Centre Hospitalier Universitaire de Nīmes
• Investigators: Principal Investigator: Tu Anh Tran, MD, PhD, Centre Hospitalier Universitaire de Nīmes

Publications and helpful links

General Publications

• Filleron A, Tran TA, Hubert A, Letierce A, Churlaud G, Kone-Paut I, Saadoun D, Cezar R, Corbeau P, Rosenzwajg M. Regulatory T cell/Th17 balance in the pathogenesis of paediatric Behcet disease. Rheumatology (Oxford). 2021 Dec 24;61(1):422-429. doi: 10.1093/rheumatology/keab253.

Study record dates

Study Major Dates

• Study Start (Actual): February 1, 2015
• Primary Completion (Actual): July 12, 2017
• Study Completion (Actual): July 12, 2017

Study Registration Dates

• First Submitted: December 11, 2014
• First Submitted That Met QC Criteria: December 12, 2014
• First Posted (Estimated): December 15, 2014

Study Record Updates

• Last Update Posted (Estimated): November 19, 2025
• Last Update Submitted That Met QC Criteria: November 17, 2025
• Last Verified: March 1, 2019

More Information

Terms related to this study

• Keywords: cytokines; Tregs; bacterial translocation
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Pathologic Processes; Immune System Diseases; Hemorrhage; Skin Manifestations; Hypersensitivity; Hematologic Diseases; Skin Diseases; Blood Coagulation Disorders; Skin Diseases, Vascular; Hemostatic Disorders; Hemorrhagic Disorders; Vasculitis; Purpura; Immune Complex Diseases; Pathological Conditions, Signs and Symptoms; Skin and Connective Tissue Diseases; Signs and Symptoms; Hemic and Lymphatic Diseases; IgA Vasculitis; Investigative Techniques; Specimen Handling; Clinical Laboratory Techniques; Diagnostic Techniques and Procedures; Diagnosis; Punctures; Surgical Procedures, Operative; Blood Specimen Collection
• Other Study ID Numbers: AOIt/2013/TAT-01; 2013-A01264-41 (Other Identifier: ANSM)