Figure 5.

Responsiveness of PBMCs from the middle-aged healthy and the PD groups to BM-MSC suppression of cytokine production. Compared with PHA-activated PBMCs, BM-MSCs co-cultured with PBMCs decreased the secretion of (A) TNF-α and (B) IFN-γ in the young healthy, the middle-aged healthy and the PD patient groups (**P<0.01). Following BM-MSC suppression, the TNF-α and IFN-γ production in the young healthy group was significantly lower than that in the middle-aged healthy group and the PD patient group (^##P<0.01). PBMCs, peripheral blood mononuclear cells; PD, Parkinson's disease; PHA, phytohemagglutinin; TNF-α, tumor necrosis factor-α; IFN-γ, interferon-γ.