A step-by-step protocol for generating human fibroblast cell-derived completely biological extracellular matrix scaffolds.

Native extracellular matrix (ECM) based scaffolds are far more superior in structural and compositional complexity than other engineered scaffolding materials such as hydrogels, electrospun fibers, and three-dimensional (3D) printed substrates. Due to the presence of native structural proteins and other macromolecules, native ECM can better restore the crucial cell-ECM crosstalk and provide a highly biomimetic microenvironment to cells. Allogenic or xenogeneic tissues have been derived by decellularization to obtain native ECM scaffolds. However, their applicability is limited by batch to batch variation, risk of pathogen transfer, undesirable immune response and scarcity of donors. Human dermal fibroblasts (hDFs) can be prescreened and maintained in a pathogen-free condition. Herein, we have described a step-by-step protocol to generate a completely biological ECM scaffold by decellularization of hDF cell sheets. Decellularization was achieved by using an anionic surfactant sodium dodecyl sulfate (SDS) and ethylene diamine tetraacetate (EDTA). The resulting ECM sheet was organized into a nanofibrous scaffold, containing major ECM structural proteins as well as other macromolecules including collagens, fibronectin, laminin and elastin. This cell-derived nanofibrous ECM is a promising scaffold material for constructing highly biomimetic functional tissues.

A Critical Review of Microelectrode Arrays and Strategies for Improving Neural Interfaces.

Though neural interface systems (NISs) can provide a potential solution for mitigating the effects of limb loss and central nervous system damage, the microelectrode array (MEA) component of NISs remains a significant limiting factor to their widespread clinical applications. Several strategies can be applied to MEA designs to increase their biocompatibility. Herein, an overview of NISs and their applications is provided, along with a detailed discussion of strategies for alleviating the foreign body response (FBR) and abnormalities seen at the interface of MEAs and the brain tissue following MEA implantation. Various surface modifications, including natural/synthetic surface coatings, hydrogels, and topography alterations, have shown to be highly successful in improving neural cell adhesion, reducing gliosis, and increasing MEA longevity. Different MEA surface geometries, such as those seen in the Utah and Michigan arrays, can help alleviate the resultant FBR by reducing insertion damage, while providing new avenues for improving MEA recording performance and resolution. Increasing overall flexibility of MEAs as well as reducing their stiffness is also shown to reduce MEA induced micromotion along with FBR severity. By combining multiple different properties into a single MEA, the severity and duration of an FBR postimplantation can be reduced substantially.

Constructing Biomimetic Cardiac Tissues: A Review of Scaffold Materials for Engineering Cardiac Patches.

Engineered cardiac patches (ECPs) hold great promise to repair ischemia-induced damages to the myocardium. Recent studies have provided robust technological advances in obtaining pure cardiac cell populations as well as various novel scaffold materials to generate engineered cardiac tissues that can significantly improve electrical and contractile functions of damaged myocardium. Given the significance in understanding the cellular and extracellular structural as well as compositional details of native human heart wall, in order to fabricate most suitable scaffold material for cardiac patches, herein, we have reviewed the structure of the human pericardium and heart wall as well as the compositional details of cardiac extracellular matrix (ECM). Moreover, several strategies to obtain cardiac-specific scaffold materials have been reviewed, including natural, synthetic and hybrid hydrogels, electrospun fibers, decellularized native tissues or whole organs, and scaffolds derived from engineered cell sheets. This review provides a comprehensive analysis of different scaffold materials for engineering cardiac tissues.

An update on the impact of food allergy on anxiety and quality of life.

PURPOSE OF REVIEW: Food allergies have become more common, and management involves dietary avoidance that can impair quality of life. Patients and families must manage the daily risk of anaphylaxis at each meal. The purpose of this review is to describe the impact of food allergies on quality of life and to provide an update on new developments in food allergy management, particularly peanut allergy. RECENT FINDINGS: Food allergy requires careful avoidance of common and ubiquitous dietary allergens. Living with food allergy is associated with annual economic costs in excess of $4000 per child, in addition to risks of anxiety and depressive symptoms. An expert panel sponsored by the 2017 National Institute of Allergy and Infectious Diseases published addendum guidelines for the prevention of peanut allergy, which suggest three separate approaches to peanut protein introduction for infants at various levels of risk. SUMMARY: Clinicians must be aware of underappreciated burdens faced by children and families with food allergies. Management involves a partnership between primary and specialty care. Mitigation strategies to improve quality of life for patients include efforts to avoid overdiagnosis in synergy with balanced counseling about the risks of food allergies. Experimental food allergen desensitization can improve quality of life but remains investigational at this time. For patients with significant anxiety, interdisciplinary management involving professional counseling may be helpful. Risk stratification and early introduction of peanut protein can help prevent the development of peanut allergy.