Prefrontal Cortex Transcriptomic Deconvolution Implicates Monocyte Infiltration in Parkinson's Disease

Although not considered a primary cause, neuroinflammation is associated with many neurodegenerative disorders, including Parkinson's disease (PD).

To elucidate potential immune involvement in PD, the present study imputed immune cell abundances from bulk RNA-sequencing transcriptomic data of PD postmortem prefrontal cortices. CIBERSORTx, an RNA deconvolution algorithm that implements support vector regression, was used to measure the relative abundances of immune cells from a previously published gene expression dataset. Through this machine-learning approach, relative proportions of 22 immune cell subtypes present in the original brain tissue were estimated.

Prefrontal cortices from PD patients exhibited significantly higher relative abundances of monocytes compared to neuropathologically normal controls (p value = 0.0005). The relative proportions of the other 21 immune subtypes showed no significant differences between control and PD samples.

The findings corroborate previous reports and suggest monocytes may be involved in PD pathogenesis.