Vascularization of Human Acellular Dermal Matrices: A Comparative Study in a Nonhuman Primate Model.

Four human acellular dermal matrices (hADMs) were characterized in a nonhuman primate abdominal wall repair model by evaluating host immune response, vascularization, and incorporation into host tissues. AlloDerm™ (electron beam-sterilized hADM [e-hADM]), AlloMax™ (gamma beam-sterilized hADM, freeze-dried [g-hADM-FD]), DermaMatrix™ (hADM, freeze-dried [hADM-FD]), and FlexHD™ (ethanol-treated hADM [EtOH-hADM]) were each implanted in an abdominal wall-bridging defect in nonhuman primates ( = 3 animals/time point, = 36 animals). Immunohistochemical and histological assessments were conducted on biopsies from each hADM at 1-, 3-, and 6-months postimplantation to assess vascularization (hematoxylin and eosin [H&E], CD31, alpha smooth muscle actin [αSMA], collagen IV), inflammatory/immune response (H&E, CD3, CD20, CD68), and collagen turnover (H&E, matrix metalloproteinase-9 [MMP-9]).

In Vitro Characterization of Fat Grafts Processed Using the REVOLVE ENVI System versus Decantation.

Background: This preclinical study evaluated benchtop/in vitro properties and fat viability and activity of grafts processed using the REVOLVE ENVI 600 system compared with decantation and evaluated properties of REVOLVE ENVI waste.

Methods: Lipoaspirate from six donors was processed using REVOLVE ENVI or decantation. The composition of each graft, hematocrit/red blood cell content, fat particle size/macrostructure, viable adipocyte count, and adipocyte activity were analyzed.

Betadine Soaking of Silicone Coupons Minimally Impacts Acellular Dermal Matrix Incorporation in a Preclinical Primate Model.

Background: Microbial pathogens local to prosthetic breast devices may promote infection, inflammation, and capsular contracture. Although antimicrobial solutions have been used, their effects on human acellular dermal matrix (HADM) incorporation when used with prosthetic devices are unknown. The authors' objective was to histologically assess the effect of 10% povidone iodine (PI)-saturated tissue expander (TE) exposure on HADM biological response in a primate model.

Acellular Dermal Matrix Susceptibility to Collagen Digestion: Effect on Mechanics and Host Response.

Various tissue origins and manufacturing processes can differentially affect the retention of native properties of acellular dermal matrices (ADMs); however, comparative studies are limited. Head-to-head comparisons between different configurations of porcine-derived Strattice (Allergan Aesthetics, an AbbVie Company, Irvine, CA) and bovine-derived SurgiMend (Integra LifeSciences, Billerica, MA) ADMs were performed to evaluate mechanical integrity and host tissue biologic response. Thermodynamic profile and morphology, which affect retention of mechanical strength, were evaluated through differential scanning calorimetry, scanning electron microscopy, and histology.

Porcine bone-patellar tendon-bone xenograft in a caprine model of anterior cruciate ligament repair.

The use of human tissue-derived autografts and allografts continues to be the gold standard in anterior cruciate ligament (ACL) repair. However, autografts and allografts have their own set of associated risks. Many alternative options, including synthetic replacements, have failed to demonstrate long-term success.

Process-induced extracellular matrix alterations affect the mechanisms of soft tissue repair and regeneration.

Extracellular matrices derived from animal tissues for human tissue repairs are processed by various methods of physical, chemical, or enzymatic decellularization, viral inactivation, and terminal sterilization. The mechanisms of action in tissue repair vary among bioscaffolds and are suggested to be associated with process-induced extracellular matrix modifications. We compared three non-cross-linked, commercially available extracellular matrix scaffolds (Strattice, Veritas, and XenMatrix), and correlated extracellular matrix alterations to in vivo biological responses upon implantation in non-human primates.

Implantation of a porcine acellular dermal graft in a primate model of rotator cuff repair.

Background: Non-cross-linked xenogeneic extracellular matrix graft materials have typically elicited a hypersensitivity reaction when implanted into humans or other primates. The purpose of this study was to examine the histologic and immune response to a non-cross-linked porcine-derived dermal extracellular matrix graft processed to remove the α-gal epitope.

Materials And Methods: Eight African green monkeys were implanted with porcine acellular dermal matrix (Conexa Reconstructive Tissue Matrix; Tornier Inc, Edina, MN, USA) to repair and augment a partial excision defect of the supraspinatus tendon of the rotator cuff.

Retention of structural and biochemical integrity in a biological mesh supports tissue remodeling in a primate abdominal wall model.

Aim: Suboptimal clinical outcome following the implantation of porcine-derived tissue matrices may be due to the method of processing the material to achieve an acellular graft and to reduce the immune response to xenogeneic epitopes. The ability to produce a porcine-based graft material that retains the structural integrity of the extracellular matrix and minimizes the potential antigenic response to the galactose-alpha(1,3)-galactose terminal disaccharide (alpha-Gal) may allow the scaffold to support regeneration of native tissue.

Materials & Methods: Porcine dermal tissue was processed to remove cells and DNA, and minimize the presence of alpha-Gal via specific enzymatic cleavage.

Host response to implanted porcine-derived biologic materials in a primate model of abdominal wall repair.

Three commercially available porcine-derived biologic meshes were implanted in an Old World primate abdominal wall resection repair model to compare biological outcome as a predictor of clinical efficacy. Tissues were explanted over a 6-month period and evaluated for gross pathology, wound healing strength, mesenchymal cellular repopulation, vascularity, and immune response. In vivo functional outcomes were correlated with in vitro profile for each material.