Novel Concepts of “Niche-Relief” and “Niche-Voltage” for Stem Cells as a Base of Bone and Hematopoietic Tissues Biomimetic Engineering

Abstract

-An affect of relief features and quantitative variables of artificial surfaces on structural-functional status of human lung prenatal stromal cells (HLPSC) and remodeling of Balb/c mice bone/bone marrow system have been studied. Implants with rough (Ra>2 μm) calcium phosphate micro-arc coatings have structural-functional sites (micro-regions) named "niches-relief" which are necessary for maturation and differentiation of HLPSC into secreting osteoblasts in shortterm culture. Maximal remodeling of mouse bone/bone marrow system in 45-day subcutaneous heterotopic test in vivo is also noted under optimal parameter (average index of cellular alkaline phosphatase area to artificial micro-region area is about 43 %) of osteogenic niche in vitro. Probable physical mechanism of osteogenic niche functioning has been determined. It correlates with increasing of electron work function (ϕ) supplied with a negative charge of calcium phosphate nanorelief in the sockets (artificial "niches"). "Niche-voltage" concept for bone tissue biomimetic engineering was proposed.

Zn- or Cu-Containing CaP-Based Coatings Formed by Micro-arc Oxidation on Titanium and Ti-40Nb Alloy: Part I—Microstructure, Composition and Properties

“…Sammons et al [ 48 ] noted that the surface roughness could be varied in the full range from nano- to microscopic scales positively impact the biological interaction between the implant and bone tissue, as it has the same order of values as cells and large biomolecules. At the same time, in [ 49 ] it has been shown that microporous biocoatings’ surfaces with the roughness of 2.5 µm < Ra < 5.0 µm promote successful stromal stem cell’s adhesion, proliferation, and differentiation into the bone tissue. However, in [ 50 ], the authors point out that the surface of implants with nano-roughness is more applicable as it promotes the adhesion of osteoblastic cells, intensifies cells’ functions (alkaline phosphatase synthesis, calcium deposition, and collagen secretion) and prevents the growth of “competitive” fibroblast cells.…”

Nanoscale Electrical Potential and Roughness of a Calcium Phosphate Surface Promotes the Osteogenic Phenotype of Stromal Cells

“…A quantitative assessment of the effect of CP microroughness on HLPSC differentiation into osteoblasts has led us to speculate that separate osteogenic microterritories for MSCs must exist in the ECM and may be reconstructed artificially [ 28 ]. The CP microrelief and electrical voltage have been proposed as key factors in the function of osteogenic niches [ 62 ].…”

“…Microarc CP rough surfaces are capable of supporting an HLPSC 3D culture in the presence of osteogenic supplements (β-glycerophosphate, dexamethasone, and ascorbic acid) [ 28 , 62 ].…”

“…We previously named the sockets on the CP surface populated by ALP-stained (osteoblast marker) stromal cells artificial osteogenic “niches” [ 62 ]. Our culture strategy was used for the current experiments; however, osteogenic supplements were absent from the culture medium.…”

“…The present work developed an approach involving functionalization of a substrate surface while considering both the micro/nanoscale relief (“niche-relief” concept) and EP (“niche-voltage” concept) [ 62 ] for prospective multilevel bone tissue engineering.…”