Bone Marrow Stromal Cell Adhesion and Morphology on Micro- and Sub-Micropatterned Titanium

Abstract

The objective of this study was to investigate the adhesion and morphology of bone marrow derived stromal cells (BMSCs) on bulk titanium (Ti) substrates with precisely-patterned surfaces consisting of groove-based gratings with groove widths ranging from 50 micro m down to 0.5 micro m (500 nm). Although it is well known that certain surface patterning enhances osteoblast (bone-forming cell) functions, past studies on cell-pattern interactions reported in the literature have heavily relied on surface patterning on materials with limited clinical relevance for orthopedic applications, such as polymeric substrates. The clinical need for improving osseointegration and juxtaposed bone formation around load-bearing Ti implants motivated this in vitro study. BMSCs were selected as model cells due to their important role in bone regeneration. The results showed significantly greater BMSC adhesion density and more favorable cell morphology on sub-micropatterned gratings when compared with larger micropatterned gratings and non-patterned control surfaces after both 24 hr and 72 hr cultures. We observed increasing cellular alignment and elongation with decreasing feature size. We also identified two distinctive cellular morphologies: Type I-Attached and spread cells that elongated along the pattern axes; and Type II-Superficially adhered round cells. Sub-micropatterned gratings demonstrated significantly greater Type I cell density than the non-patterned control, and lower Type II cell density than the larger micropatterned gratings. Collectively, these results suggest potential for rationally designing nano-scale surface topography on Ti implants to improve osseointegration.

Micro- and Nanopatterned Topographical Cues for Regulating Macrophage Cell Shape and Phenotype

“…Our results show that for Ti substrates, micro and nano-grooved topographies caused macrophages to elongate along the direction of the grooves, consistent with previous studies with other cell types on similar substrates. 32-33 Interestingly, the degree of cell elongation level was biphasic and decreased when cells were cultured on grooves less than 200 nm or greater than 10 μm. When the grooves were too narrow, cells did not elongate likely because adhesions could not form.…”

Degradation behaviors and cytocompatibility of Mg/β‐tricalcium phosphate composites produced by spark plasma sintering

“…BMSCs were harvested from the femur and tibia of 3‐week‐old female Sprague Dawley rats following the established protocol, approved by the Institutional Animal Care and Use Committee (IACUC) at University of California at Riverside . BMSCs were cultured under standard cell culture conditions in 25 ml media, which was prepared by supplementing Dulbecco's modified Eagle medium (DMEM; Sigma‐Aldrich, MO) with 10% fetal bovine serum (HyClone, UT) and 1% penicillin–streptomycin (P/S; Life Technologies, CA).…”

“…Determine in vitro cytocompatibility of Mg/β-TCP composites with BMSCs in direct culture BMSCs were harvested from the femur and tibia of 3-weekold female Sprague Dawley rats following the established protocol, approved by the Institutional Animal Care and Use Committee (IACUC) at University of California at Riverside. 37 BMSCs were cultured under standard cell culture conditions in 25 ml media, which was prepared by supplementing Dulbecco's modified Eagle medium (DMEM; Sigma-Aldrich, MO) with 10% fetal bovine serum (HyClone, UT) and 1% penicillin-streptomycin (P/S; Life Technologies, CA). The 5 × 5 × 1 mm samples, including Mg/10% β-TCP composite, Mg/20% β-TCP composite, sintered Mg, and extruded Mg, were polished with silicon carbide abrasive papers until 1200 grit, cleaned by soaking in acetone and ethanol, and disinfected under UV radiation for each side of surfaces for at least 4 hr.…”

A systemic study on key parameters affecting nanocomposite coatings on magnesium substrates

“…The euthanasia of the rats and harvesting of cells from the rats were approved by the Institutional Animal Care and Use Committee (IACUC) at the University of California at Riverside. The BMSC culture method was established previously [50].…”