Development and application of 3D cellular visualization technology for tooth and oral mucosa

Abstract

The oral cavity has a significant relationship with overall health because oral health can be a critical indicator as a window that reflects overall health. Monitoring detailed cellular and molecular mechanisms of progressive symptoms in the oral cavity must be necessary for preventing the deterioration of oral diseases into systemic diseases or for the diagnosis of early symptoms of specific systemic diseases. However, cellular-level dynamics of inflammatory response in the oral cavity are poorly understood because of technical limitations. Herein, our custom-built laser-scanning microscopy system was applied for the development of the 3D spatiotemporal cel-lular visualization of teeth and oral mucosa and for the investigation of dynamic changes in immune cells in the pathogenesis of the dental pulpitis model and oral contact allergy model.

I successfully optimized the tooth optical clearing technique by modification of Murray’s clear method. Using the optimized tooth optical clearing method, I performed the 3D cellular-level visualization of spatiotemporal change of CD11c+ cells in dental pulp in the acute pulpitis model. The tooth optical clearing-based compre-hensive 3D cellular-level visualization can be an efficient method for analyzing cellular behaviors of various pulpal cells in normal and pathological conditions in a quantitative manner.

I established the micro probe-based confocal endomicroscopy by integrating the custom-built laser scanning confocal microscopy system with the GRIN lens. By using the GRIN confocal endomicroscopy, in vivo multi-cellular wide-area visualization of the oral mucosa was achieved in a non-invasive manner. In addition, longi-tudinal intravital visualization of the oral mucosa in the DNFB-derived oral contact allergy mouse model showed highly dynamic spatiotemporal changes of various types of immune cells in response to the allergic challenges. The GRIN confocal endomicroscopy system can be a highly useful tool for investigating the com-plex pathophysiology of diseases in the oral cavity.