Fig. 9: Oral ulcer healing efficacy of PolyLA-Na/PolyLA patch in mini-pig model.

a Scheme depicting creation of mini-pig mucosa defect that was covered by PolyLA-Na/PolyLA patch to accelerate healing; b Photographs of buccal mucosa defect in mini-pig treated by PolyLA-based patch and chitosan film at the 0, 3, 5, and 8 days; c Tracking of wound-bed closure after treating with different methods for 0, 3, 5, and 8 days; d Wound healing efficiency of the oral ulcers at days 3, 5, and 8 days after treated with PolyLA-Na/PolyLA patch and chitosan film (n = 3); e, f H&E staining and Masson’s trichrome staining of the regenerated mini-ping oral mucosa at day 8 (n = 3 biologically independent samples in each group); g Sirius red staining of type I collagen (red) and type III collagen (green) in the regenerated mini-ping oral mucosa at day 8; h–j Immunofluorescence staining of CK5 (red), CD31 (red) and iNOS (red) antibody in regenerated oral mucosa at 8 days; k Analysis of the collagen I/III ratio in Sirius red staining (n = 3); l–n Quantification of expression levels of CK5, CD31, and iNOS in regenerated oral mucosa (n = 3) CK5 cytokeratin 5, CD31 platelet endothelial cell adhesion molecule-1, iNOS inducible nitric oxide synthase. (All presented data are mean values ± SD from the mean from n = 3 independent measurements on independent samples. All p values were calculated using a two-sided Student’s t test).