Stem Cell-Induced Inflammation in Cholesteatoma is Inhibited by the TLR4 Antagonist LPS-RS

Cholesteatoma is a severe non-cancerous lesion of the middle ear characterized by massive inflammation, tissue destruction, and an abnormal growth keratinized squamous epithelium. We recently demonstrated presence pathogenic stem cells within cholesteatoma tissue, unfortunately their potential roles in regulating disease-specific chronic inflammation remain poorly understood. In presented study, we utilized our established human vitro cell model for treatments with lipopolysaccharides (LPS), tumor necrosis factor α (TNFα), TLR4-antagonist LPS from R. sphaeroides (LPS-RS) followed qPCR, western blot, immunocytochemistry. Middle (ME-CSCs) showed significantly increased expression TLR4 accompanied enhanced LPS-dependent pro-inflammatory gene pattern TNFα, IL-1α, IL-1ß, IL-6, IL-8 compared to non-pathogenic control cells. ME-CSCs was driven activity NF-B p65 leading TNFα-mediated feed-forward-loop target expression. Functional inactivation via LPS-RS blocked ME-CSCs, resulting nearly complete loss TNFα summary, determined that mediate inflammatory environment TLR4-mediated NF-B-signaling, suggesting distinct role as drivers progression on therapeutic target.