TG and Parkinson disease: To further demonstrate that increasing TLR2 expression triggers neurotoxic and neuro-inflammatory cascades similar to those observed in patients with PD/DLB and in high expresser α-synuclein mouse model line (Fig. 1), we next delivered a TLR2-overexpressing lentiviral vector (LV-TLR2) into the brains of non-tg and an α-synuclein low expresser (1–1.5 fold) transgenic mouse (α-syn-tg, under the PDGFβ promoter, D line) (Fig. 2; Additional file 1: Figure S1) [23].