Photobiomodulation of a flowable matrix in a human skin ex vivo model demonstrates energy-based enhancement of engraftment integration and remodeling.

The use of dermal substitutes to treat skin defects such as ulcers has shown promising results, suggesting a potential role for skin substitutes for treating acute and chronic wounds. One of the main drawbacks with the use of dermal substitutes is the length of time from engraftment to graft take, plus the risk of contamination and failure due to this prolonged integration. Therefore, the use of adjuvant energy-based therapeutic modalities to augment and accelerate the rate of biointegration by dermal substitute engraftments is a desirable outcome. The photobiomodulation (PBM) therapy modulates the repair process, by stimulating cellular proliferation and angiogenesis. Here, we evaluated the effect of PBM on a collagen-glycosaminoglycan flowable wound matrix (FWM) in an ex vivo human skin wound model. PBM resulted in accelerated rate of re-epithelialization and organization of matrix as seen by structural arrangement of collagen fibers, and a subsequent increased expression of alpha-smooth muscle actin (α-SMA) and vascular endothelial growth factor A (VEGF-A) leading to an overall improved healing process. The use of PBM promoted a beneficial effect on the rate of integration and healing of FWM. We therefore propose that the adjuvant use of PBM may have utility in enhancing engraftment and tissue repair and be of value in clinical practice.

Genetic susceptibility to keloid scarring: SMAD gene SNP frequencies in Afro-Caribbeans.

Keloid disease (KD) is a fibroproliferative dermal tumour of unknown aetiology. The increased familial clustering in KD, its increased prevalence in certain races and increased concordance in identical twins suggest a strong genetic predisposition to keloid formation. The highest incidence of keloids is found in the black population, where it has been estimated around 4-6% and up to 16% in random samples of black Africans. SMAD genes 3, 6 and 7 were investigated as candidate genes in Jamaican patients with keloid scars (n = 183) and a matched control population (n = 121) because of their previously reported involvement in fibrotic disorders and to determine if they were associated with keloid disease susceptibility. Thirty Five SNPs across these genes were genotyped using Time-of-Flight Mass Spectrometry (MALDI-TOF MS) and iPLEX assay. Linkage disequilibrium (LD) was established between several of the SNPs investigated. In the Jamaican population, the SMAD SNPs investigated for this study were not strongly associated with increased risk of developing KD. Identification of genetic markers in candidate genes such as the SMAD family may be of significant importance in diagnosis, prognosis and development of new therapies in the management of keloid scarring.