Anti-ficolin-2 Autoantibodies in Lupus Nephritis

Study Overview
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Brief Summary
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Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by the production of multiple autoantibodies. The prevalence and significance of antibodies against Ficolin-2 have not been yet investigated. The aims of this study were to determine the prevalence of anti-ficolin-2 antibodies among SLE patients and to investigate their potential as diagnostic and/or prognostic biomarkers in SLE. This study is a secondary phase of a serum sample analysis done in early 2015 in order to determine the prevalence of anti-ficolin-2 antibodies among the same cohort as the previously declared study (ClinicalTrials.gov ID: NCT02625831; Unique Protocol ID: 1841851v0). In this retrospective study, clinical data were obtained from medical files and blood samples were selected from preexisting biological collection. SLE patients (n=165) were informed and did not objected, they were matched to healthy controls (n=48). Disease activity was determined according to the SLEDAI score. Anti-ficolin-2 antibodies levels were measured in sera by ELISA and correlated to previously obtained Anti-ficolin-3, Anti-ficolin-2, anti-dsDNA and anti-C1q antibodies levels. The titer of anti-ficolin-2 antibodies was correlated with the SLEDAI score (p<0.0001). The presence of anti-ficolin-2 antibodies was associated with anti-ficolin-3 antibodies, anti-C1q and anti-dsDNA antibodies. Interestingly, the combination of anti-ficolin-3, anti-ficolin-2 and anti-C1q antibodies demonstrated higher specificity than any other traditional biomarker. These results suggest that anti-ficolin-3 and anti-ficolin-2 antibodies could be useful for the diagnosis of active nephritis in SLE patients.

Detailed Description
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For this retrospective study, the well written brief summary should be sufficient.

Official Title
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Association Between the Presence of Autoantibodies Targeting Ficolin-2 and Active Nephritis in Patients With Systemic Lupus Erythematosus

Conditions
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Lupus Erythematosus, Systemic

Intervention / Treatment
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* Other: BIological analysis


Participation Criteria
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Eligibility Criteria
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165 SLE patients Inclusion Criteria: Age: ≥ 18 years old Patients with lupus diagnostic criteria (ACR1997) Exclusion Criteria: Pregnant women Patient with known evolutive cancer 48 healthy patients matched in age and sex with one or several SLE patients

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| SLE patient<br>165 SLE patients. Subgroup : 77 with active lupus and 88 in disease remission. in the active subgroup : 36 with lupus nephritis and 41 without. Biological analysis were performed. | Other: BIological analysis<br>* Biological analysis : ficolin-2 et anti-ficolin-2 antibodies<br>* Other names: Biological analysis on preexisting;|
| healthy patients<br>48 healthy patients. Biological analysis were performed. | Other: BIological analysis<br>* Biological analysis : ficolin-2 et anti-ficolin-2 antibodies<br>* Other names: Biological analysis on preexisting;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Anti-ficolin-2 antibodies presence in SLE patients | Anti-ficolin-2 antibodies in SLE patients, considered positive if superior than 95 arbitrary units. This study have a single visit approach with serum collection so every outcome is measured at T0, which is the only visit for the patient. | measured at day of inclusion = T0 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation of anti-ficolin-2 antibodies with anti-DNA antibodies in SLE patients | Correlation between Anti-ficolin-2 antibodies presence and anti-DNA antibodies presence. This study have a single visit approach with serum collection so every outcome is measured at T0, which is the only visit for the patient. | measured at day of inclusion = T0 | 
| Correlation of anti-ficolin-2 antibodies with anti-C1q antibodies in SLE patients | Correlation between Anti-ficolin-2 antibodies presence and anti-C1q antibodies presence. This study have a single visit approach with serum collection so every outcome is measured at T0, which is the only visit for the patient. | measured at day of inclusion = T0 | 
| Correlation of anti-ficolin-2 antibodies with lupus activity (SLEDAI score) in SLE | Correlation between Anti-ficolin-2 antibodies presence and clinical and/or biological evidence of SLE activity according to SLEDAI score (2012). This study have a single visit approach with serum collection so every outcome is measured at T0, which is the only visit for the patient. | measured at day of inclusion = T0 | 
| Correlation of anti-ficolin-2 antibodies presence with active nephritis in SLE patients | Correlation between Anti-ficolin-2 antibodies presence and clinical and/or biological evidence of active nephritis This study have a single visit approach with serum collection so every outcome is measured at T0, which is the only visit for the patient. | measured at day of inclusion = T0 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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ficolin-2, anti-ficolin-2 antibodies, lupus nephritis, Lupus Erythematosus, Systemic, biomarker, ficolin-3, anti-ficolin-3 antibodies