With the Through wound healing, keratinocytes at the skin wound edge progressively cover the wound by means of proliferation and migration, forming a new epithelium around the surface of proliferating In the course of wound healing, keratinocytes in the skin wound edge progressively cover the center on the wound through proliferation and migration, forming a new epithelium on the surface of proliferating granulation tissue. The SIKVAV-modified chitosan hydrogel promoted skin woundMolecules 2018, 23,6 ofMolecules 2018, 23, x FOR PEER REVIEW6 ofgranulation tissue. The SIKVAV-modified chitosan hydrogel promoted skin wound re-epithelialization (Figure 2). On day (Figuretrauma, keratinocytes migrated a further distanceafrom thedistance from re-epithelialization 3 soon after two). On day three soon after trauma, keratinocytes migrated further wound edge in wound + chitosan group mice, than in the control, peptide, and chitosan mice groups. On day theSIKVAV edge in SIKVAV + chitosan group mice, than inside the manage, peptide, and chitosan mice five just after trauma, five soon after trauma, keratinocytes in the wound web-sites of mice within the SIKVAV + chitosan groups. On daykeratinocytes in the wound websites of mice in the SIKVAV + chitosan group fully covered the wound surface then completed re-epithelialized. Keratinocytes did Keratinocytes group completely covered the wound surface after which completed re-epithelialized.not completely cover the wound surfaces of mice inside the control, peptide, and chitosan groups at this time. On day did not absolutely cover the wound surfaces of mice within the handle, peptide, and chitosan groups at 7 soon after trauma, the chitosan group the chitosan group mice completed neither the APRIL Proteins Recombinant Proteins handle group nor this time. On day 7 soon after trauma, mice completed re-epithelization, butre-epithelization, but neither peptide group did. the control group nor the peptide group did.three.three. The SIKV AV-Modified Chitosan Hydrogel Promoted Skin Wound AngiogenesisFigure 2. HE staining showed that the wounds have been re-epithelialized on days 3, five or 7 immediately after trauma in Figure two. HE staining showed that the wounds have been re-epithelialized on days 3, five or 7 soon after trauma in mice in the control, SIKVAV, chitosan, and SIKVAV-modified chitosan groups (scale bar: 50 black mice inside the handle, SIKVAV, chitosan, and SIKVAV-modified chitosan groups (scale bar: 50 ). (The m). frame indicates the junction the junction in between the re-epithelialization and non-re-epithelialization (The black frame indicates among the re-epithelialization and non-re-epithelialization in the skin wound. The which means of 1 and two signifies that theand two signifies that the above correspondingrepresents a DSG2 Proteins site magnified within the skin wound. The which means of 1 above corresponding image is enlarged. 1 picture is enlarged. 1 image on the black frame around the left, and two represents a the left, and two represents a magnified the best.). represents a magnified picture on the black frame on magnified picture from the black frame on image on the black frame on the ideal.).New blood vessels in wounds give nutrition for wound granulation tissue and new three.3. The SIKVAV-Modified Chitosan Hydrogel Promoted Skin Wound Angiogenesis keratinocytes, which play a vital part in wound healing. Within this study, the expression of CD31 on New blood vessels in wounds give nutrition for wound granulation tissue and new the surface of endothelial cells in newly formed capillaries was analyzed by immunohistochemistry; the keratinocytes, which play an important role in wound healing. In t.