ABSTRACT
OBJECTIVE: To examine the ability of OASIS Wound Matrix to absorb, retain, and protect bioactive molecules from solution. DESIGN: Samples of OASIS Wound Matrix were incubated in solutions of bioactive molecules, specifically heparin, albumin, fibronectin, basic fibroblast growth factor 2, and platelet-derived growth factor (PDGF). Half of the samples were then rinsed, and all of the samples were evaluated using enzyme-linked immunosorbent assays (ELISAs) and dye-mediated spectrophotometric methods for absorption and retention of the bioactive molecules. Protection of PDGF was measured by placing PDGF-incubated and control samples into a degradation solution containing plasmin. Intact PDGF levels were then evaluated using a PDGF-specific ELISA. MAIN OUTCOME MEASURES: The main outcome measures were the amount of each bioactive molecule that was absorbed after incubation in solutions and retained after rinses as well as the amount of PDGF remaining after plasmin degradation. MAIN RESULTS: OASIS Wound Matrix absorbed bioactive molecules from solution, selectively absorbed PDGF from serum, and protected PDGF from protease degradation. CONCLUSIONS: Although OASIS Wound Matrix potentially has multiple functions in wound healing, it likely promotes wound healing, in part, by absorbing, retaining, and protecting bioactive molecules from the wound environment.
Subject(s)
Biological Dressings , Extracellular Matrix/transplantation , Intestinal Mucosa/cytology , Intestine, Small/cytology , Wound Healing , Wounds and Injuries/therapy , Absorption , Albumins/metabolism , Albumins/pharmacokinetics , Animals , Anticoagulants/pharmacokinetics , Biological Dressings/standards , Chronic Disease , Drug Evaluation, Preclinical , Enzyme-Linked Immunosorbent Assay , Fibroblast Growth Factor 2/metabolism , Fibroblast Growth Factor 2/pharmacokinetics , Fibronectins/metabolism , Fibronectins/pharmacokinetics , Heparin/pharmacokinetics , Humans , Platelet-Derived Growth Factor/metabolism , Platelet-Derived Growth Factor/pharmacokinetics , Spectrophotometry , Swine , Wounds and Injuries/metabolismABSTRACT
BACKGROUND: Porcine small intestinal submucosa (SIS) has been studied for body wall repair. However, the best method to implant the biological material has not been investigated. The objective of this study was to compare tensile strengths achieved after healing when SIS was placed using three implant techniques (onlay, inlay, underlay) in a porcine model of abdominal wall defect. MATERIALS AND METHODS: Twenty female domestic pigs had three abdominal midline sites assigned to one of five test groups: SIS implantation using inlay, onlay, or underlay technique; sham surgery (sutured midline incision) or normal body-wall control. Full-thickness muscle/fascia midline abdominal defects (6 x 4 cm) were surgically created and then repaired using eight-layer SIS. Healing was evaluated at 1 and 4 post-operative months by tensile strength testing and histopathology. RESULTS: Hernias were not observed. Tensile strengths were not statistically different between the five test groups (P = 0.39) or between months 1 and 4 (P = 0.35). The caudal site was stronger than the cranial or middle sites in the 1 month group (P < 0.0001). Histologically, healing appeared to progress over time as the repair site showed remodeling towards an interlacing fibrous connective tissue pattern. CONCLUSIONS: No significant differences in tensile strength were found between implant techniques and were not statistically different from sham surgery and normal control tissue. This study suggested that SIS healing/remodeling provides sufficient tensile strength for the repair of ventral (anterior) abdominal wall defects when implanted using any of three common techniques.
