We developed an automated microregistration method that enables repeated in vivo skin microscopy imaging of the same tissue microlocation and specific cells over a long period of days and weeks with unprecedented precision. Applying this method in conjunction with an in vivo multimodality multiphoton microscope, the behavior of human skin cells such as cell proliferation, melanin upward migration, blood flow dynamics, and epidermal thickness adaptation can be recorded over time, facilitating quantitative cellular dynamics analysis. We demonstrated the usefulness of this method in a skin biology study by successfully monitoring skin cellular responses for a period of two weeks following an acute exposure to ultraviolet light.
Keywords: UV radiation; epidermal; human skin; in vivo cell tracking; in vivo cellular imaging; in vivo microscopy; longitudinal study; melanin; multiphoton microscopy; reflectance confocal microscopy; second harmonic generation; two-photon excitation fluorescence.