Altered dendritic cell subset distribution in patients with Parkinson's disease: Impact of CMV serostatus

- Frequencies of plasmacytoid DCs were similar in PD patients and controls.
- Frequencies of pro-inflammatory CD16+ILT2high myeloid DCs were higher in CMV-positive PD patients than CMV-positive controls.
- ILT2 expression on myeloid DCs positively correlated with total UPDRS levels (p = 0.014) in CMV + PD patients.

Parkinson's disease (PD) is characterised by low-level systemic inflammation, which may be at least partly due to pathophysiological activation of immunity. Here, the frequencies of different types of circulating dendritic cells (DCs) with and without a pro-inflammatory phenotype were determined in PD patients and controls. A high proportion of older people is infected with cytomegalovirus (CMV), which acts as a chronic antigenic stressor that could also contribute to increased inflammation. Following this idea, we found higher frequencies of myeloid DCs with a pro-inflammatory CD16 + ILT2high phenotype in CMV-positive PD patients than controls, suggesting the potential involvement of CMV in exacerbating PD.

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