Biomedical E ngineer ing
Cellular Crash Test
•  Indenter rings are used to
generate strain.
•  Collision of the shuttle with the
impact base drives the indenter
into flexible base of cell culture
insert.
•  Strain magnitude is sensitive to
indenter height.
•  Strains up to 50%
Biomedical E ngineer ing
Cellular Crash Test
The shuttle is designed to carry six
cell culture inserts.
Cell Culture Insert
1.
Polypropylene Well (A)
2.
Porous Polyurethane
membrane base (A)
3.
Supports dense (400K cells)
cell culture (B)
4.
Flexible membrane can be
stretched (C to D)
Biomedical E ngineer ing
Cell Impact Testing
•  Role of force in ECM production
•  Rat astrocytes
•  400K / well
•  The key impact parameters
explored were
1.  Media Type: serum vs.
serum free)
2.  Impact number: single
versus double impact
3.  Impact type: decel only
(150g) or decel with strain
(20%)
Biomedical E ngineer ing
Cell Viability
•  MTT assay (colorimetric)
•  24 hours after last impact
•  Key findings
1.  Significant cell death
following two impacts.
2.  Sensitive to both decel only
and combined impacts
3.  Greater cell death in serum
free cultures
Biomedical E ngineer ing
Gene Expression
•  qRTPCR
•  Collagen I, Versican, Neurocan
•  Key findings
1.  ECM gene expression was
generally reduced in
response to impact of both
types.
2.  Largest decreases in
response to double impacts
3.  Serum free cultures were less
responsive