Figure 1

Toll-like receptor 4 expression in sensory neurons. (A) Western blot analysis of Toll-like receptor 4 (TLR4) isolated from trigeminal root ganglion (TRG) and lumbar L3-L6 dorsal root ganglion (DRG) lysates. (B-M) Immunofluorescent images of TLR4 in peptidergic and non-peptidergic DRG populations from sectioned naïve L4 or L5 DRGs. NeuN is a neuronal marker (B, green arrowheads), which co-labeled with TLR4 (C, red arrowheads). Nuclei are stained with DAPI (D, H, L, blue). Merged images demonstrate co-labeling of NeuN containing neurons with TLR4 (E, yellow arrowheads). Calcitonin gene-related peptide (CGRP) is a marker for peptidergic-containing sensory neurons (F, green arrowheads), which co-labeled with TLR4 (G, red arrowheads). Merged images demonstrate co-labeling of CGRP-containing neurons with TLR4 (I, yellow arrowheads). Isolectin B4 (IB4) is a marker for non-peptidergic sensory neurons (J, green arrowheads), which co-labeled with TLR4 (K, red arrowheads). Merged images show co-labeling of IB4 non-peptidergic sensory neurons with TLR4 (M, yellow arrowheads). Scale bar is 60 μm (B-M).