Therapeutic Evaluation of Low-dose IL-2-based Immunomodulatory Approach in Patients With Early AD

Inclusion Criteria: * Patients aged \> 18 * Age of disease onset \< 70 years * Clinical and biological diagnosis of AD based on * Progressive amnestic syndrome associated or not with other cognitive impairments * Biological criteria: CSF biomarkers suggestive of AD. * Brain MRI congruent with the diagnosis, left to the appreciation of the investigator * CDR (Clinical Dementia Rating Scale) = 0.5 or 1 * If patients have an antidepressant or acetylcholinesterase inhibitors treatment, patients must be treated with stable doses of treatment for at least 1 month before inclusion. * Have a caregiver who provides a separate written informed consent to participate. If a caregiver/study informant cannot continue, one replacement is allowed. * Have adequate vision and hearing for neuropsychological testing in the opinion of the investigator. * Have given written informed consent approved by the ethical review board (ERB) governing the site. * The patient has to have a French social security number and be fluent and literate in French. Exclusion Criteria: * Subject with a psychiatric evolutionary and/or badly checked. * Subject with a grave, severe or unstable pathology (left to the judgement of the investigator) the nature of which can interfere with the variables of evaluation. * Epileptic subjects * Subject under guardianship or curatorship * Subject presenting contraindications to the MRI * Known or supposed history (\< or = 5 years) of severe alcoholism or misuse of drugs * Vascular, inflammatory or expansive, visible lesion in the MRI, which can interfere on the criteria of diagnosis. * No health insurance * Women of childbearing potential: a woman is considered of childbearing potential (WOCBP), i.e. fertile, following menarche and until becoming post-menopausal unless permanently sterile. Permanent sterilisation methods include hysterectomy, bilateral salpingectomy and bilateral oophorectomy. A postmenopausal state is defined as no menses for 12 months without an alternative medical cause. * History of auto-immune disease * History within the past 10 years of a primary or recurrent malignant disease * Diagnosis or history of other possible etiology of dementia, including but not limited to other neurodegenerative disorders (FTD, LBD, VaD, HD, PD, PSP-CBD). * Renal dysfunction at inclusion, clearance \<30 mL/min * Chronic hepatic diseases as indicated by liver function tests abnormalities * Abnormal thyroid function * Therapeutic trial within 1 year preceding the first study period, or participation in a trial with active or passive immunization against amyloid if patient was assigned to the active treatment arm. * Clinically significant evidence of Active viral infection (CMV, EBV, HCV, HBV, TPHA-VDRL, HIV) * Current or medical history of severe cardiopathy, * \- Severe dysfunction in a vital organ * Patients with White Blood Count (WBC) \< 4.000/mm3; platelets \< 100.000/mm3; hematocrit (HCT) \< 30%. * Patients with serum bilirubin and creatinine outside normal range. * Patients with organ allografts. * Patients who are likely to require corticosteroids