Study of Immune Thrombocytopenia Pathogenesis:

Study of Immune Thrombocytopenia Pathogenesis: a Multicenter, Open and Controlled Study.

Immune thrombocytopenia (ITP) is an autoimmune disease characterized by a low platelet count responsible for bleedings. The disease is mostly mediated by antiplatelet antibodies produced by specific B cells. However, T cells are also involved but their role is not completely understood.

The aim of this study is to determine the implication of T cells in the pathogenesis of ITP, notably regulatory T cells (Treg, CD4+CD25highFoxp3+), cytotoxic T cells (CD3+CD8+) and T follicular helper cells (TFH, CD3+CD4+CXCR5+PD-1+ICOS+), in blood and in the spleen of primary ITP patients, compared to healthy controls.

Inclusion Criteria:

• Patients with ITP, defined as thrombocytopenia < 30 G/L, once causes related to infection, medication, systemic auto-immune disease or malignant hemopathy have been ruled out
• persons who have provided written informed consent

Exclusion Criteria:

• persons without national health insurance
• persons under 18 years old
• patients under guardianship
• pregnancy
• subjects suffering from a systemic auto-immune disease, cancer, a progressive infection, or treated with steroids or immunosuppressants.