Effects of systemic pretreatment with CpG oligodeoxynucleotides on skin wound healing in mice

• Published in: Wound repair and regeneration 2013-09, Vol.21 (5), p.723-729
• Main Authors: Hergert, Bettina, Grambow, Eberhard, Butschkau, Antje, Vollmar, Brigitte
• Format: Article
• Language: English
• Subjects: Adjuvants, Immunologic - administration & dosage; Adjuvants, Immunologic - pharmacology; Animals; Cell Movement; Drug Administration Schedule; Fibroblasts - drug effects; Immunohistochemistry; Inflammation - drug therapy; Keratinocytes - drug effects; Male; Mice; Mice, Inbred C57BL; Oligodeoxyribonucleotides - administration & dosage; Oligodeoxyribonucleotides - pharmacology; Reverse Transcriptase Polymerase Chain Reaction; Skin - pathology; Toll-Like Receptor 9 - metabolism; Treatment Outcome; Wound Healing - drug effects; Wounds and Injuries - drug therapy; Wounds and Injuries - pathology
• ISSN: 1067-1927; 1524-475X
• DOI: 10.1111/wrr.12084

Unmethylated CpG oligodeoxynucleotides (ODN) bind to the Toll‐like receptor 9, thus stimulating the immune system. To study the effects of systemic pretreatment with CpG ODN on dermal regeneration, C57BL6/J Tyr mice were treated with CpG or control ODN 6 days prior to implantation of a dorsal skinfold chamber and skin wounding. Wound epithelialization was analyzed by planimetric microscopy. On day 18, wound tissues were taken for (immuno)histochemical staining. CpG ODN increased epithelialization compared with control ODN treatment. Histological analysis revealed reduced capillary density, reduced wound cellularity, and reduced numbers of infiltrating leukocytes, as well as reduced F4/80‐positive macrophages, but increased numbers of RELM‐α‐positive M2 macrophages after CpG ODN treatment, reflecting a better quality of wound healing on day 18 compared with control ODN treatment. Reverse transcription‐polymerase chain reaction analysis of Toll‐like receptor 9 showed the receptor expression on both fibroblasts and keratinocytes. Fibroblasts showed an increase of migration upon increasing dosages of CpG and not control ODN, reaching ∼50% of the response of basic fibroblast growth factor‐exposed cells. Keratinocytes dose‐dependently responded to both CpG and control ODN up to values found in keratinocyte growth factor‐exposed cells. In summary, CpG ODN support late tissue‐remodeling processes that contribute to resolution of inflammation and solid wounds during skin regeneration.