Three-dimensional imaging of human skin and mucosa by two-photon laser scanning microscopy

Background: Various structural components of human skin biopsy specimens are difficult to visualize using conventional histologic approaches. Methods: We used two-photon microscopy and advanced imaging software to render three-dimensional (3D) images of in situ nerves, blood vessels, and hair follicles labeled with various fluorescent markers. Archived frozen human skin biopsy specimens were cryosectioned up to 150 mum in thickness and fluorescently stained with rhodamine- or fluorescein-labeled antibodies or lectins. Optical sections were collected by two-photon microscopy and the resulting data sets were analyzed in three dimensions using Voxx software. Results: Reconstructed image volumes demonstrated the complex 3D morphology of nerves, blood vessels and adnexal structures in normal mucocutaneous tissue. Conclusion: Two-photon microscopy and Voxx rendering software allow for detailed 3D visualization of structures within human mucocutaneous biopsy specimens, as they appear in situ , and facilitate objective interpretation of variations in their morphology. These techniques may be used to investigate disorders involving cutaneous structures that are difficult to visualize by means of traditional microscopy.