Biological functionality of extracellular matrix-ornamented three-dimensional printed hydroxyapatite scaffolds.

Three-dimensional (3D) printing is considered an ideally suitable method to fabricate patient specific implantable devices. The approach enabled to produce a porous scaffold with tailored physical, mechanical, and biological properties because of the flexibility to tune the scaffold architecture. The objective of the study described was to elucidate the determining role of cell-laid extracellular matrix (ECM) in impacting biological response. In this regard, to mimic the natural ECM environment or the attributes of the native tissue, a natural ECM analogue surface was produced on the 3D printed and sintered hydroxyapatite (HA) scaffold surface by the mineralized ECM of the osteoblast. This involved the growth of osteoblast on 3D printed scaffolds, followed by differentiation to deposit the mineralized ECM on the biomaterial surface. The cells were removed from the mineralized matrix using freeze-thaw cycles to obtain a decellularized extracellular matrix (dECM) on the biomaterial surface. Subsequently, seeding of osteoblast on dECM-ornamented HA scaffolds led to 3D growth with enhanced expression of prominent proteins, actin and vinculin. Based on preliminary observations of present study, it was underscored that HA scaffolds-ornamented with dECM provided an optimized microenvironment conducive to the growth of 3D structural tissue and favorably promoted biological functionality because of the availability of an environment that promoted cell-cell and cell-scaffold interaction. The primary advantage of dECM is that it enabled constructive remodeling and promoted the formation of tissue in lieu of less functional tissue. The study opens-up a new path for printing of 3D structures suitable to treat segmental bone defects.