Localization of interleukin-6 signaling complex in epithelialized apical lesions of endodontic origin.

IL-6, IL-6R, and gp-130 localized to mononuclear inflammatory cells, vascular endothelial cells, and immature proliferating epithelia in a diffuse pattern and in mature lining epithelia in a localized cell membrane pattern, supporting a role for epithelial proliferation during cyst formation. Additional cell membrane co-localization of IL-6 receptor complex suggests classic signaling involvement in addition to trans-signaling.