Quantitative Assessment of Angiogenesis in Skin Wound Healing by Multi-Optical Imaging Techniques

Abstract

The primary goal of wound healing therapy is to quickly close the wound and form healthy and functional scar tissue. As capillary system regeneration is an important condition for skin wound healing, it is important to dynamically monitor angiogenesis with multiple methods based on the 3D reconstruction of dermal microcirculation. In this study, we established a quantitative system to comprehensively evaluate angiogenesis and perfusion during wound healing. Full-thickness skin wounds were generated on the back of rats. Laser Doppler anemometer (LDA), laser speckle contrast imaging (LSCI), and medical electronic dermoscopy (MED) are used to observe the vasculature from the horizontal plane and quantify blood perfusion in wounds. We combined immunofluorescence staining and two-photon excited fluorescence microscopy (TPEF) to reconstruct 3D vessels for longitudinal quantification. These results indicated that new blood vessels around the wound grew parallel to the wound surface. The shape of the blood vessels changed from curved to straight, and the density of the surrounding vascular network gradually decreased as manifested by a decrease in the nodes and branches and the total length of the blood vessels. There were dense blood vessels that grew vertically to the wound surface in the center of the wound. This study established a real-time, non-invasive system to monitor re-epithelialization and angiogenesis and quantitatively assess blood vessels during wound healing, which facilitates the evaluation of new treatments for wound healing.

Antibacterial Collagen‐Based Nanocomposite Dressings for Promoting Infected Wound Healing

“…[ 19a ] The high‐density vascular system can transport sufficient oxygen and nutrients to the wound site, which is conductive to cell proliferation, cell migration, and metabolic activities related to wound healing. [ 41 ] To sum up, antibacterial collagen‐based nanocomposite dressings can relieve the inflammatory reaction by killing pathogenic bacteria, and induce the generation of blood vessels and the orderly deposition of collagen in the wound site, thus promoting wound remodeling and healing.…”

Dynamic evaluation of pathological changes in a mouse acne model by optical imaging technology

“…To evaluate the wound healing and repair process of the acne skin lesions, a previously published evaluation method by our group was used 9 . H&E staining was performed, and on the 7th day, the wound of the lesions and new hair follicles nearby were observed (Figure S2a).…”

“…Our group has conducted research on optical imaging technology, utilizing various cellular and animal models and others in vivo and ex vivo assays, 27,28 such as ear swelling in mice, 8 back trauma healing in rats 9 and skin burns in mice 27 . Based on this, this research had established four dimensions of optical imaging using the dermatoscope, OCT, TPEF and the LSCI technique to assess the pathological progression of the mouse acne model in the dorsum (Figure 6).…”

“…We also found that TPEF could dynamically monitor the thickness of the epidermis in vivo, which was highly consistent with results obtained from HE staining 8 . We also employed optical coherence tomography (OCT), laser speckle contrast imaging (LSCI), dermatoscope and other optical imaging techniques to assess skin diseases such as burns and wound healing 9,10 . The previous researches we conducted have established a foundation for the application of optical imaging technology in the diagnosis and efficacy evaluation of skin diseases.…”

“…8 We also employed optical coherence tomography (OCT), laser speckle contrast imaging (LSCI), dermatoscope and other optical imaging techniques to assess skin diseases such as burns and wound healing. 9,10 The previous researches we conducted have established a foundation for the application of optical imaging technology in the diagnosis and efficacy evaluation of skin diseases. In this study, we utilized a mouse back acne model that closely resembles clinical acne lesions and employed multiple nondestructive optical imaging techniques to reveal the occurrence, development and changes of acne in vivo.…”