Role of the Neonatal Fc Receptor for IgG in the Pathophysiology of Lupus

Completed

• Conditions: Lupus Erythematosus, Systemic
• Interventions: Other: Blood samples

• Registration Number: NCT03896373
• Lead Sponsor: University Hospital, Tours

Brief Summary

This study evaluates the expression of the neonatal fc receptor (FcRn) in white blood cells and antigen-presenting cells (APC) in active lupus patients compared to inactive lupus patients and control to investigate if it's upregulated or not.

Detailed Description

FcRn is an intracellular receptor which binds the Fc of immunoglobulins G (IgG) and albumin which induce an upgraded half-life of this two proteins.

It's extended role involve the regulation of immune complexes and anti-tumoral immunity, some studies showing a direct correlation between it's expression and the tumor surface and prognosis.

Recently a role in the upregulation of humoral response with a increase of the antibodies's diversity and a more efficient priming of lymphocyte B have been evocated.

The lupus erythematosus is an auto-immune disease mediated by IgG and immune complexes characterized by a high diversity of autoantibodies and a large dysregulation of the immune system in all it's components.

In this study, by analogy with the founding in anti-tumoral immunity, the investigators hypothesised that in an active lupus disease the expression of FcRn is upregulated in the white blood cells and in APC.

This is followed by an extended half life of IgG autoantibodies and immune complexes inducing direct damages by their deposit in tissues and indirectly by upregulating the humoral response, leading to anormal production of a large panel of autoantibodies.

Study Timeline

• Study First Submitted: 2019-03-27
• Study First Submitted QC: 2019-03-28
• Study First Posted: 2019-04-01
• Study Start: 2019-04-17
• Primary Completion: 2020-10-18
• Study Completion: 2020-10-18
• Status Verified: 2021-02
• Last Update Submitted: 2021-02-23
• Last Update Posted: 2021-02-24

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 48

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Lupus erythematosus	Blood samples	Patients with inactive lupus erythematosus, active lupus erythematosus or newly diagnosed

Primary Outcome Measures

Name	Time	Method
Expression of FcRn in active or newly diagnosed lupus erythematosus compared with inactive lupus erythematosus	At baseline	Measurement in flow cytometry of the fluorescence's mean of FcRn in each type of white blood cells

Secondary Outcome Measures

Name	Time	Method
IGHG1 genotyping	At baseline	IGHG1 gene polymorphism analysis
Expression of FcRn in CD16 monocytes	At baseline	CD16 is used to differentiate subpopulation of monocytes. The investigators will evaluate the correlation between expression of CD16 and the fluorescence's mean of FcRn measured in flowcytometry.; This measure will be done for each population of participants
Expression of FcRn in macrophages	At baseline	After a positive selection of monocytes obtained from participants, the investigators will measure the fluorescence's mean of FcRn in this cells for each population of participants
FcRn genotyping (FCGRT)	At baseline	FcRn gene polymorphism analysis (FCGRT)

Trial Locations

Locations (2)

Internal Medicine Service, University Hospital, Tours; 🇫🇷 Tours, France

Nephrology Service, University Hospital, Tours; 🇫🇷 Tours, France