Biological Scaffolds that Mimic Function and Structure of Basement Membranes

Abstract

Biological scaffolds mimicking basement membranes are valuable tools to study biological processes like cellular differentiation and phenotypic maintenance in vitro. Such artificial basement membranes also hold great promise for engineering tissues and organs and promoting regenerative processes. Basement membrane‐like sheets were fabricated by electrospinning of nanofibers with fiber size, geometry, and the porosity of authentic basement membranes. Nanofibers were electrospun from pure murine laminin 111, murine reconstituted basement membrane (containing laminin, type IV collagen and perlecan) and human cardiac muscle basement membrane enriched in laminins 411 and 511). These proteins and complex extracts were blended with polymers such as polycaprolactone to create hybrid nanofibers with mechanical properties determined by the degradable polymer and biological properties derived from laminin. Importantly, the protein and hybrid nanofibers, unlike others reported, required no chemical crosslinking, which often disrupts biological activity, to maintain structure. These biological scaffolds were compared to films of pure laminin 111 and the mouse and human basement membrane extracts for their ability to maintain the pluripotent state of induced pluripotent stem cells and embryonic stem cells in defined media. All cell lines examined attached more rapidly and to a greater extent on the nanofibrous basement membrane scaffolds, and antibody and enzymatic staining for a variety of markers of pluripotency showed they resisted the tendency to differentiate in vitro for weeks when maintained on these substrates. Next we examined the ability of the scaffolds to promote attachment and differentiation of mesenchymal stem and PC12 cells to a neuron‐like phenotype. The basement membrane like scaffolds promoted neuronal precursor attachment and differentiation to neuron‐like cells in serum free media without the addition of cAMP or nerve growth factor, suggesting a possible biomimetic effect on differentiation from the scaffold. Together these initial studies illustrate methods to create substrates that mimic native basement membranes in structure and function‐‐these scaffolds may take our in vitro models a bit closer to the in vivo situation.Support or Funding InformationResearch generously supported by: Virginia Biosciences Health Research Corporation Grant, Nanofabrication of Tissue ScaffoldsThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.