IL-1β, IL-2, IL-6 and TNF-α production by peripheral blood mononuclear cells from patients with Parkinsonʹs disease

The capacity of peripheral blood mononuclear cells (PBMC) from patients with treated Parkinsonʹs disease (PD) to produce interleukin (IL) IL-1β IL-2, IL-6, tumor necrosis factor (TNF)-α and the proliferative response to mitogens, was compared with that from cells from healthy subjects. The production of IL-2 and the mitogen response were significantly lower in PD patients, whereas the secretion of IL-1β, IL-6 and TNF-α were significantly enhanced. To evaluate the role of levodopa in creating immunological alterations, PBMC of patients and controls were incubated with concentrations of the drug extrapolated from those used in clinical practice. Levodopa caused an inhibition of mitogen-induced proliferation, stimulation of IL-6 and TNF-α production, whereas the secretion of IL-1β and IL-2 was not affected. The results of the study provide a further support for the interrelationship between the central nervous and immune system. In addition, the data indicate that the immunological alterations found in PD may be partially attributed to levodopa administration.