Clinical Research Directory

Inclusion Criteria: * Patients of both sexes * hospitalized in the Dermatology department of the CHU of Nice for moderate to severe psoriasis (defined by a PASI \> or = 10) * covered by a social security scheme after obtaining a free * Clinical diagnosis of plaque psoriasis by a dermatologist with or without type 2 diabetes (defined by glycated hemoglobin \>7%) * For the control group: without psoriasis or other inflammatory dermatosis aged in the presence or not of type 2 diabetes (glycated hemoglobin \>7%). * free and informed consent Exclusion Criteria: * Minor or incapable or unwilling to consent freely or in an informed manner Pregnant or nursing woman. * Patient in a period of exclusion from other biomedical research * Patient with generalized chronic inflammatory disease or other inflammatory dermatosis * Patients on general corticosteroid, immunomodulator or immunosuppressant therapy in the month prior to local inclusion or treatment with corticosteroid therapy in the 15 days prior to inclusion, on anti- treatmentIL-23 or anti IL12/23 for less than 3 months or under anti-IL-17 or anti-TNF treatment for less than 1 month. * Contraindication to cutaneous biospsis (known hemostasis disorder, taking anticoagulants, allergy to xylocaine, history of cheloid scars, congenital immune deficiency)