IMMUNOMODULATORY EFFECT OF CORD BLOOD-DERIVED MULTIPOTENT STEM CELLS ON LYMPHOCYTES OF PATIENTS WITH ALZHEIMER’S DISEASE

Abstract

Alzheimer's disease (AD) is a progressive neurodegenerative disease. Studies have found that inflammation in brain and peripheral circulation system plays an important role in AD. Human cord blood-derived multipotent stem cells (CB-SCs) is a new kind of stem cells which could modulate autoimmune responses by altering regulatory T cells (Tregs). We intend to investigate the immunomodulatory effect of CB-SCs on peripheral blood lymphocytes (LCs) of patients with AD and to further explore its therapeutic potency for AD. 1) CB-SCs were isolated from human cord blood and cultivated under the condition of 35°C, 8%CO2 for about 10 days. 2) LCs were isolated from peripheral blood of AD patients, and then cocultivated with CB-SCs for 3 days under the condition with or without phytohaemagglutinin-P (PHA-P) which can stimulate the proliferation of LCs. 3) The levels of cytokines including IL-1, IL-4 and IL-10 in the supernatant were detected via enzyme-linked immuno sorbent assay (ELISA). 4) The percentage of Tregs and the positive ratio of their functional cytokines such as IL-10, TGF-β1 were examined via flow cytometry. 1) CB-SCs could inhibit proliferation and aggregation of LCs induced by PHA-P. 2) The level of IL-1 worked as pro-inflammatory factor was dramatically decreased in the LCs co-cultured with CB-SCs group, while the level of the anti-inflammatory factors including IL-4 and IL-10 were significantly increased. 3) The ratio of CD4+/CD8+ T cells was significantly declined in the both co-cultured groups. 4) The proportion of Tregs was increased significantly in the LCs co-cultured with CB-SCs group that were not stimulated by PHA-P. Whereas, under the stimulation of PHA-P, the anti-inflammatory proteins expressed in the Tregs were raised significantly.