Piconewton Level Loading and Sub-Cellular Deformation of Bone Cells Using a Novel Stokesian Fluid Stimulus Probe (SFSP) Available to Purchase

A new quantifiable in vitro force probe, the Stokesian Fluid Stimulus Probe (SFSP), is developed to hydrodynamically stimulate local regions of the osteocyte whereby neither antibody decoration nor probe membrane perturbation is necessary. Osteocytes are imbedded in hard mineralized matrix where single-cell, in vivo experimentation is extremely challenging. Whole bone tissue loading induces cyclic fluid flow throughout the bone porosity to hydrodynamically load osteocytic networks within the lacunar-canalicular-system (LCS). A theoretical model has been developed to describe the fluid flow through the dynamic and structurally complex microenvironment surrounding the osteocytic network within the LCS. The model predicts tensile forces of 1–10pN to occur at discrete attachment sites connecting the osteocyte cell process to canalicular wall projections during physiological loading¹. Our new force probe’s design and implementation has successfully 1) reproduced in vivo level forces at subcellular precision to assess cellular polarity in vitro and 2) demonstrated that cellular signaling is initiated at integrin attachment sites along the cell process.