Optical clearing assisted confocal microscopy of ex vivo transgenic mouse skin

Research Techniques Made Simple: Optical Clearing and Three-Dimensional Volumetric Imaging of Skin Biopsies

“…This optical clearing ability is enhanced at higher incubation temperatures probably owing to more rapid permeation of glycerol into the skin (Deng et al, 2011). RI matching for skin using solutions closer to the collagen RI (1.43, fully hydrated; 1.53, dry), such as FocusClear (Song et al, 2015), benzyl alcohol benzoate (Abadie et al, 2018), 3DISCO, or uDISCO, also worked better for skin clearing (Xu et al, 2019).…”

“…In recent years, optical clearing has been broadly applied to a variety of species and organs, ranging from in vitro cultured organoids (Dekkers et al, 2019) to human and marmoset brains; mouse embryos (Tainaka et al, 2016) to human embryos (Belle et al, 2017); pill bugs (Konno and Okazaki, 2018) to mosquitoes (Mori et al, 2019). In the skin, ex vivo OTC has been applied for studying hair follicles of the mouse pinna (Song et al, 2015)-dermal architecture of vasculature and adipocytes and the expansion of keratinocytes during wound healing of mouse dorsal skin. Cleared human skin was imaged to reveal auto-fluorescent sweat glands, sebaceous glands, hair follicles, and the cutaneous plexus (Foster et al, 2019); epidermal hyperplasia in psoriatic skin (Abadie et al, 2018); and epidermal nerve atrophy in pruritic skin such as atopic dermatitis and psoriasis (Tan et al, 2019) (Figure 2e).…”

Investigating the optical clearing effects of 50% glycerol in ex vivo human skin by harmonic generation microscopy

“…One of the most important mechanisms is the refractive index matching, which is to reducing the scattering inside the tissue. However, in different tissues such as sclera 3 , liver [4][5][6] , muscle 7 , tendon 5,7 , skin 5,[8][9][10][11][12][13][14][15][16][17][18][19][20][21] , the OC effect varies. Among these studies, skin optical clearing with glycerol attracts high attention 5,[8][9][10][11][12][13][14][15]17,18,[20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36]…”

“…However, the skin is a high scattering tissue that comprises multiple layers with a variation of refractive index. Although OC of human skin have been studied by many different optical imaging techniques such as near-infrared (NIR) spectrophotometer 9 – 12 , 23 , 29 , 36 , confocal microscopy 13 , 14 , multi-photon microscopy 8 , 15 , 35 , SHG microscopy 8 , and optical coherence tomography (OCT) 5 , 12 , 17 , 18 , 26 , 29 , 30 , 34 , 36 , 37 in the past few decades, the effects and mechanisms of optical clearing in human skin with glycerol topically applied are not fully understood and are with inconsistent results, especially for the case of glycerol at low concentration. Observation of the OC effect inside the topmost epidermis layer is thus important to understand its mechanisms for topical applications.…”

FSOCA‐induced switchable footpad skin optical clearing window for blood flow and cell imaging in vivo

“…It was well known that surgical operations were always accompanied with bleeding and changes of the normal physiological environment during process of model establishment . Recently, the rapidly developed tissue optical clearing (TOC) technique provides an alternative solution through topical application of optical clearing agents (OCAs) on the dorsal skin, which demonstrated its powerful capacity in optimizing the imaging performances, including the imaging depth, resolution, contrast and sensitivity, of various optical imaging modalities, e. g. laser speckle contrast imaging , photoacoustic microscopy , optical coherence tomography , confocal microscopy , two‐photon microscopy and flow cytometry , etc.…”