Showing papers by "Jean E. Schwarzbauer published in 2018"

Cell-derived decellularized extracellular matrices.

Abstract: The ability to create cell-derived decellularized matrices in a dish gives researchers the opportunity to possess a bioactive, biocompatible material made up of fibrillar proteins and other factors that recapitulates key features of the native structure and composition of in vivo microenvironments. By using cells in a culture system to provide a natural ECM, decellularization allows for a high degree of customization through the introduction of selected proteins and soluble factors. The culture system, culture medium, cell types, and physical environments can be varied to provide specialized ECMs for wide-ranging applications to study cell-ECM signaling, cell migration, cell differentiation, and tissue engineering purposes. This chapter describes a procedure for performing a detergent and high pH-based extraction that leaves the native, cell-assembled ECM intact while removing cellular materials. We address common evaluation methods for assessing the ECM and its composition as well as potential uses for a decellularized ECM.

Mechanistic insights into the cellular effects of a novel FN1 variant associated with a spondylometaphyseal dysplasia.

Abstract: Spondylometaphyseal dysplasia (SMD) is characterized by developmental changes in long bones and vertebrae It has large phenotypic diversity and multiple genetic causes, including a recent link to novel variants in the extracellular matrix (ECM) protein fibronectin (FN), a regulator of ECM assembly and key link between the ECM and proper cell function We identified a patient with a unique SMD, similar to SMD with corner fractures The patient has been followed over 19 years and presents with short stature, genu varum, kyphoscoliosis, and pectus carinatum Radiography shows metaphyseal changes that resolved over time, vertebral changes, and capitular avascular necrosis Whole exome sequencing identified a novel heterozygous FN1 variant (pCys97Trp) Using mass spectroscopy, mutant FN was detected in plasma and in culture medium of primary dermal fibroblasts isolated from the patient, but mutant protein was much less abundant than wild-type FN Immunofluorescence and immunoblotting analyses show that mutant fibroblasts assemble significantly lower amounts of FN matrix than wild-type cells, and mutant FN was preferentially retained within the endoplasmic reticulum This work highlights the importance of FN in skeletal development, and its potential role in the pathogenesis of a subtype of SMD

Impact of Acellular Dermal Matrix on Postsurgical Wound Fluid Biomarkers in Prosthetic Breast Reconstruction.

Abstract: Background Despite the widespread practice of using biologic scaffolds for soft tissue reinforcement over prosthetic implants, the impact of acellular dermal matrix (ADM) on surgical wound fluid biomarkers over the initial postoperative period after prosthetic breast reconstruction remains poorly understood. Methods Patients undergoing prosthetic breast reconstruction surgery where ADM was likely to be used were consented to have fluid samples collected from surgical drains after surgery. Sample collections occurred at an "Early" time point at 24 to 48 hours after surgery and then a "Late" time point approximately 1 to 2 weeks after surgery. All procedures were performed by a single surgeon. Acellular dermal matrix was placed when prosthetic coverage with autologous tissue could not be achieved. Laboratory analyses were performed in blinded fashion without the knowledge of whether the samples came from the ADM "Present" or "Not Present" group. Results Twenty-one patients were in the ADM Present group and 18 patients were in the Not Present group. Both groups showed similar demographics based on age and body mass index. Analyses for cell concentration, protein concentration, extracellular matrix protein levels, cell proliferation activity, and matrix metalloproteinase activity showed no significant differences between wound fluid samples from the 2 groups. Conclusions The presence of ADM does not appear to significantly impact wound biomarkers in prosthetic breast reconstruction. The current study provides useful data regarding the impact of ADM on surgical wound fluid during the initial postoperative period, laying important groundwork for more extensive future studies on the impact of biologic scaffolds on wound biology.