The Nonlinear Spectral Imaging Technique Of Extracellular Matrix

Collagen and elastin, as the major components in the extracellular matrix (ECM), are intrinsic indicators of physiological and pathological states. Here, we have developed a high-contrast nonlinear optical imaging technique to imaging collagen and elastin by detecting simultaneously two photon-excited fluorescence (TPEF) from elastin and second-harmonic generation (SHG) from collagen about scar margin and skin lesion with mucinosis. First,2D large-area and3D focused images of elastin and collagen at scar margins were obtained to extract quantitative parameters. It indicated that alteration degree can potentially serve as quantitative indicators to examine wound healing, scar progression over time and discriminate different types of scars. Second, collagen microstructure about cutaneous mucinosis skin was visualized by second harmonic generation (SHG) microscopy to gain structural and diagnostic information. High resolution images of collagen in the dermis of skin lesion with mucinosis and healthy skin showed differences in their microstructures. Our results demonstrated the possibility of SHG imaging to in vivo tracking the pathological process of mucinosis and evaluate the therapeutic efficacy.