Fibrin with laminin‐nidogen reduces fibrosis and improves soft palate regeneration following palatal injury

This study aimed to analyze the effects of fibrin constructs enhanced with laminin‐nido-gen, implanted in the wounded rat soft palate. Fibrin constructs with and without laminin‐nidogen were implanted in 1 mm excisional wounds in the soft palate of 9‐week‐old rats and compared with the wounded soft palate without implantation. Collagen deposition and myofiber formation were analyzed at days 3, 7, 28 and 56 after wounding by histochemistry. In addition, immune staining was performed for a‐smooth muscle actin (a‐SMA), myosin heavy chain (MyHC) and paired home-obox protein 7 (Pax7). At day 56, collagen areas were smaller in both implant groups (31.25 ± 7.73% fibrin only and 21.11 ± 6.06% fibrin with laminin‐nidogen)) compared to the empty wounds (38.25 ± 8.89%, p < 0.05). Moreover, the collagen area in the fibrin with laminin‐nidogen group was smaller than in the fibrin only group (p ˂ 0.05). The areas of myofiber formation in the fibrin only group (31.77 ± 10.81%) and fibrin with laminin‐nidogen group (43.13 ± 10.39%) were larger than in the empty wounds (28.10 ± 11.68%, p ˂ 0.05). Fibrin‐based constructs with laminin‐nidogen reduce fi-brosis and improve muscle regeneration in the wounded soft palate. This is a promising strategy to enhance cleft soft palate repair and other severe muscle injuries.