Clinical trial NCT01715623: Polymorphism of the IgH Locus Regulatory Region as a Prognostic Factor During Immune Pathologies.
Official title: Polymorphism of the IgH Locus Regulatory Region as a Prognostic Factor During Immune Pathologies.
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Healthy Volunteers
Children With HSP
Subject With Allergy
Lymphoma
Keywords: polymorphism
serum Ig
Lead sponsor: University Hospital, Limoges
Sponsor class: OTHER
Collaborators: name: Institut National de la Santé Et de la Recherche Médicale, France
name: Direction Générale de la Santé, France
First posted: 2012-10-29
Enrollment: 486
Sex: ALL
Minimum age (years): 4
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: PROBABILITY_SAMPLE
Study population: 4 populations :

* Healthy Volunteers
* subjects with HPS
* subjects with peanut allergy or hymenoptera venom allergy
* lymphoma (biological collection)

Brief summary: The investigators previously showed that both antibody class switching (from IgM to IgG, IgA or IgE) and antibody secretion are controlled by a polymorphic "3' regulatory region" (3'RR) of the immunoglobulin heavy chain (IgH) locus. Alleles of the 3'RR have shown influences on the severity and progression of IgA nephropathy (IgAN) (with an over-representation of the B allele among patients with severe kidney IgA deposits). Allele B also constitutes a risk factor for celiac disease, herpetiform dermatitis, psoriasis and rheumatoid arthritis. Since the 3'RR now appears as a crucial regulator of Ig production, we wish to check whether its genetic polymorphism might influence not only the occurrence of immunopathologic processes involving class-switched antibody deregulated production but also the severity of such diseases or the time course of their progression. We wish to focus on two conditions involving class-switched antibodies: on one hand the severe forms of IgE hypersensitivities, and on the other hand a disease involving pathogenic IgA and for which the prognosis is currently very difficult to predict at the onset of the disease: Henoch-Schonlein purpura (HSP).

Regarding hypersensitivities, the diversity of their clinical manifestations prompt us to focus on homogeneous groups of patients and we thus wish to concentrate on two groups of patients who are frequently referred to the hospital: severe allergies to Hymenoptera venoms and severe food allergies related to peanut allergens sensitization. These groups will be built by considering multiple clinical criteria (clinical history, severity of the manifestations, positive skin tests, and positive oral provocation tests for peanut allergens...) and biological criteria authenticating the mechanisms of the disease (high specific serum IgE, demonstration of specific basophil activation by the allergen...).

In parallel to the study in patients, we will include a large cohort of healthy controls (400 individuals), in order to be able to decipher whether correlations can be seen between:

* IgH 3'RR genotypes
* The serum accumulation of the various Ig classes, including IgG subclasses, IgA (which are sometimes depicted as protective, sometimes as tolerogenic and anti-inflammatory) and IgE (highly pro-inflammatory and responsible for hypersensitivities)
* IgG allotypes (with 6 frequent IgG haplotypes known in human and previously reported as correlated with varying levels of IgG and IgE production in normal individuals).

Detailed description: This study should thus finally provide answers to 5 questions which are currently un-addressed:

* How the 3'RR alleles are linked to IgG allotypes and corresponding IgH haplotypes?
* Is there a physiological link between 3'RR alleles and production of the various Ig classes and sub-classes?
* Is the 3'RR polymorphism connected with the risk of more severe forms of allergic diseases?
* Is the 3'RR polymorphism connected with the risk of occurrence and/or severe evolution of HSP?
* Is the oncogenicity of translocations affecting the IgH locus connected to the strength of the 3'RR allelic variants?

Eligibility criteria: Inclusion Criteria:

* Healthy Volunteers:

Age ≥ 18 and \< 50 years No history of allergy, haematological malignancies or immune diseases

* Subjects with allergy:
* Children:

Age ≥ 4 and \< 18 years Clinical history supporting the diagnosis of severe food allergy Peanut specific IgE (Arah2) -Adults: Age \> 18 and \< 60 years History of severe reaction after antigenic challenge Anaphylactic shock already experienced Specific IgE or positive BAT Positive prick tests

* subject with HPS:
* Children:

Age ≥ 4 and \< 18 years Henoch Schonlein Purpura (HSP) documented by Ankara 2008 criteria

-Adult: Henoch Schonlein Purpura(HSP) with renal involvement Adults ≥ 18 years,

Exclusion Criteria:

* subject with allergy or subject with Henoch Schonlein Purpura(HSP): known pregnancy patient under guardianship
* Healthy Volunteers:

Allergy known pregnancy patient under guardianship

Primary outcomes:
measure: the percentage of allele B
timeFrame: one day
Secondary outcomes:
Other outcomes:
Locations:
city: Limoges
country: France
facility: Clinical Investigation Center
city: Limoges
country: France
facility: Nephrology
city: Limoges
country: France
facility: Pediatric
city: Limoges
country: France
facility: Pneumology
Study officials:
affiliation: Limoges UH
name: Michel COGNE, MD
role: PRINCIPAL_INVESTIGATOR
References: