Pediatric ALL, Rheumatoid Purpura
Conditions
Brief summary
In this ancillary study on the FoxTreg cohort, the study investigators will select variables to input and thus develop two models (Linear Discriminant Analysis and Decision Tree). The aim of this study is to validate the method in terms of repeatability, reproducibility, control of pre-analytical conditions and sample conservation, to complete the screening of IgA glycosylation in individuals of the FoxTreg cohort and to refine the glycopeptide signature to predict renal involvement.
Interventions
OTHERMass Sepctrometry
Mass spectrometry (LC/MS) of purified immunoglobulins
Sponsors
Centre Hospitalier Universitaire de Nīmes
Study design
Observational model
COHORT
Time perspective
RETROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
3 Years to 16 Years
Healthy volunteers
Yes
Inclusion criteria
Patient sera from biobank of the FoxTreg study (NCT02317133)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Glycopeptide signature of serum from children with Rheumatoid Purpura | Day 0 | Mass spectrometry to identify the glycopeptides present and their level |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Reproducibility of mass spectrometry in measuring glycopeptide signature | Day 0 | Mass spectrometry to identify the glycopeptides present and their level |
| Control of conservation of samples for measuring glycopeptide signature | Day 0 | Mass spectrometry to identify the glycopeptides present and their level |
| Glycopeptide signature of serum from all patients of the cohort | Day 0 | Mass spectrometry to identify the glycopeptides present and their level |
| Difference between a normally glycosylated IgA and an IgA with GalNac polymer in Rheumatoid Purpura patients with / without renal impairment versus controls | Day 0 | Mass spectrometry to identify the glycopeptides present and their level |
| Number of subjects with IgA glycosylation abnormalities in Rheumatoid Purpura patient population with renal impairment polymer in Rheumatoid Purpura patients with / without renal impairment versus controls | Day 0 | Mass spectrometry of IgA |
| Percentage of subjects with IgA glycosylation abnormalities in Rheumatoid Purpura patient population with renal impairment polymer in Rheumatoid Purpura patients with / without renal impairment versus controls | Day 0 | Mass spectrometry of IgA |
| Number of subjects with IgA glycosylation abnormalities in each group | Day 0 | Mass spectrometry of IgA |
| Repeatability of mass spectrometry in measuring glycopeptide signature | Day 0 | Mass spectrometry to identify the glycopeptides present and their level |
| Serum immunoglobulin levels in patients with acute Rheumatoid Purpura and in remission | Day 0 | Mass spectrometry of immunoglobulins IgA, IgM and IgG (g/L) |
| Quantification of blood cell lines in patients with acute Rheumatoid Purpura and in remission. | Day 0 | Blood cell lines, particularly Treg and Breg (number/mm3) |
| Serum cytokine levels in patients with acute Rheumatoid Purpura and in remission | Day 0 | pg/ml of TGF-β, IL-1, IL-6, TNF-α, IL-8, IL-10 and IL-17 |
| Bacterial Translocation in patients with Rheumatoid Purpura | Day 0 | Plasma levels of 16S rDNA (copies/µl) |
| Plasma levels of LBP in patients with Rheumatoid Purpura | Day 0 | µg/ml |
| Plasma levels of CD14s in patients with Rheumatoid Purpura | Day 0 | µg/ml |
| Bacterial diversity in the gut microbiota in patients with Rheumatoid Purpura | Day 0 | Diversity Index |
| Percentage of subjects with IgA glycosylation abnormalities in each group | Day 0 | Mass spectrometry of IgA |
Countries
France
Outcome results
None listed