Measuring bone cell adhesion on implant surfaces using a spinning disc device

Abstract

The adhesion behaviour of osteoblastic cells on implant surfaces is a main focus during the development of osteoconductive implant surfaces. Therefore, besides cell spreading and proliferation on surfaces the adhesion strength of cells to the substrate is of high interest. There are different approaches to determine cell adhesion but only few quantitative methods. For this purpose, we have developed an adhesion device based on the spinning disc principle in conjunction with an inverse confocal laser scanning microscope (LSM). Mirror polished disc-shaped test samples made of titanium-(Ti6Al4V) and cobalt-alloys (Co28Cr6Mo), as well as stainless steel (316L), were seeded with osteoblasts, stained with a fluorescent dye, at defined radial positions and were incubated for 18 h in cell culture medium (DMEM). After incubation the test samples were placed into the adhesion chamber filled with DMEM. By means of a computer controlled motor the test samples were rotated for 3 min. Using the LSM the detachment of the cells at defined radial positions was determined and the cell count was recorded before and after rotation with the help of imaging software. An average shear stress of 47.1 N/m 2 , 53.2 N/m 2 and 49.4 N/m 2 was assessed for the mirror polished Ti6Al4V, Co28Cr6Mo and 316L surfaces respectively. The technique is suitable for studying bone cell adhesion strength on orthopaedic implant materials. Future investigations will focus on different bioactive and anti-infectious implant surfaces, as well as soluble bioactive factors.

Mechanical bone growth stimulation by magnetic fibre networks obtained through a competent finite element technique

“…One topic will be the mechanical interaction between fibres and the matrix at the interphase of these two. Biomechanical materials as used in the potential application of tissue engineering are characterized by non-linear mechanical response and additional parameters such as limited adhesion forces 64 . Those effects will be particularly important at the interface.…”

“…For the application as tissue engineering scaffold, understanding of local strain at the interface between cells and steel is mandatory. The advanced version of this current model could integrate biological aspects such as the detaching of focal adhesion points build by bone cells on the fibre structure 64 . Also a dynamic matrix model including the active migration of bone cells through the fibre network 65 after the cell seeding would be a worthwhile aspect and of great interest for understanding bone development.…”

Restricted cell functions on micropillars are alleviated by surface-nanocoating with amino groups

“…This would interfere with quantitative immunofluorescence analysis of these structures. Additionally, the PPAAm coating does not allow for the trypsinization of the cells in a vital state from the micropillared surfaces due to its high cell-attractive characteristics as measured previously by a spinning disc device ( Fritsche et al, 2010 ). MG-63 cells on PPAAm were 1.5 times more resistant to shear stress compared to cells on uncoated titanium alloys (Ti6Al4V) ( Gabler et al, 2014 ).…”

Correlation of in vitro cell adhesion, local shear flow and cell density

“…For drawing further comparisons, we consider the work of Fritsche et al 26 who measured bone cell adhesion using a spinning disc device. Comparable to our setup the authors studied bone cells adhered on titanium, but on a mirror-like polished surface and at far higher shear stresses (z50 Pa).…”