Table 2.

Summary of histological changes and skin biomarkers of PDT regarding skin remodeling.

	Histological Changes	Immunohistochemical Expression
After PDT (0 day–3 weeks)	Monocytic inflammation	Increase in MMP Increase in TGF-beta
Remodeling (3 weeks–3 months)	Lymphocytic infiltrate Dermis fibrosis Elastosis decrease	Increase in MMP-9 Increase in collagen type I
Final stage of remodeling (3–9 months)	Collagen order Elastosis decrease Thinner dermis Flattened epidermis	Decrease in MMP expression Increase of collagen type I and elastin