Relationship between [123I]FP-CIT SPECT data and peripheral CD4+T cell profile in newly-diagnosed drug-naive Parkinson's disease patients

Background Dysregulation of the CD4 + T cell compartment occurs in Parkinson's Disease (PD). Nonetheless, the exact relationship with dopamine transporter (DAT) SPECT denervation patterns is currently unknown. Methods Expression of transcription factors and levels of circulating CD4 + T cell subsets were assessed in peripheral blood mononuclear cells (PBMC) from 23 newly diagnosed drug-naive PD patients. Semi-quantitative [I-123]-FP-CIT SPECT data, i.e. uptake in the most and least affected putamen (maP, laP) and caudate (maC, laC), total striatal binding ratio (tSBR), and total putamen-to-caudate ratio (tP/C) were obtained. Results FOXP3 mRNA levels correlated with the uptake in maC (r = - 0.542, P = 0.011), laP (r = - 0.467, P = 0.033), and tSBR (r = - 0.483, P = 0.027). Concerning flow cytometry analysis of circulating CD4 + T cell subsets, a significant relationship between tP/C, caudate uptake, and the levels of both T helper (Th)1 and 2, was detected. Furthermore, we found significant correlations between the uptake in maP and the total count of naive and activated T regulatory cells (Treg) (r = - 0.717, P = 0.001; r = - 0.691, P = 0.002), which were confirmed after the Benjamini-Hochberg correction for multiple comparisons using a false discovery rate at level q = 0.10. Levels of circulating naive Treg were higher (P = 0.014) in patients with more extensive dopaminergic denervation, suggesting a compensatory phenomenon. Conclusions Peripheral CD4 + T cell immunity is involved in early-stage PD and novel correlations with striatal DAT loss were observed.

Automated summary

Dysregulation of CD4 + T cell compartment occurs in Parkinson's Disease (PD), but its relationship with dopamine transporter (DAT) SPECT denervation patterns is unknown.