Figure 2. Evaluation of the expression patterns of TLR4 and CD14 in human coronal dental pulp. Normal control dental pulp was examined for expression of TLR4 (Panel A), CD14 (Panel B), and a marker of myelinated neurons (N52, Panel C). Inflamed dental pulp (defined as teeth with a response to thermal stimulation and having deep caries lesions) had two populations of TLR4 and CD14, with TLR4 (Panel D) or CD14 (Panel G) observed in round or stellate cells or in fibers coursing through coronal pulp. At least some of these fibers expressed N52 (TLR4, Panels E,F; CD14, Panels H,I). Exposure of inflamed pulp to only the secondary antibodies produced low background signal (Panels J,K). Scale bar is 100 µm.