Flow perfusion maintains ex vivo bone viability

A novel model for bone biology research

Edward H. Davidson, Derek D. Reformat, Alessandro Allori, Orlando Canizares, I. Janelle Wagner, Pierre B. Saadeh, Stephen M. Warren

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

Encased in lacunae, osteocytes receive nutrition and biomechanical signals through the lacunocanalicular system. We have developed a novel flow-perfusion bioreactor designed to support lacunocanalicular fluid flow. We hypothesize that ex vivo fluid flow can maintain endochondral bone viability and, ultimately, serve as a novel model to study bone biology in vitro. Sprague-Dawley rat femurs were harvested, stripped of soft tissue, loaded into a custom-designed bioreactor and perfused with osteogenic culture medium. After 14days of flow-perfusion or static culture, the bones were harvested, fixed, decalcified, embedded, sectioned and stained with haematoxylin and eosin. Fresh long bone samples were similarly processed for comparison. Osteocyte viability and function were also evaluated, using thiazolyl blue tetrazolium bromide (MTT), fluorospectrophotometric DNA quantification, alkaline phosphatase (ALP) colorimetric assay and fluorochrome labelling of mineralizing surfaces. All samples remained free of infection throughout the study period. After 14days of flow perfusion, histological analysis showed normal-appearing bony architecture, with 72% of lacunae being osteocyte-filled compared with 93% in freshly harvested samples and only 36% in static samples. MTT staining and assay confirmed osteocyte viability in the flow-perfusion samples as well as in fresh samples. DNA quantification demonstrated DNA to be preserved in flow-perfused samples when compared with freshly harvested samples. ALP activity in flow-perfusion explants was upregulated compared with fresh and static samples. Fluorochrome-labelled mineralizing surfaces were seen throughout the explanted flow-perfused samples. This is the first demonstration that flow perfusion provides adequate chemotransportation to explanted murine endochondal bones.

Original languageEnglish (US)
Pages (from-to)769-776
Number of pages8
JournalJournal of Tissue Engineering and Regenerative Medicine
Volume6
Issue number10
DOIs
StatePublished - Nov 1 2012
Externally publishedYes

Fingerprint

Osteocytes
Bone
Perfusion
Bone and Bones
Research
DNA
Phosphatases
Bioreactors
Fluorescent Dyes
Alkaline Phosphatase
Flow of fluids
Assays
Hematoxylin
Eosine Yellowish-(YS)
Nutrition
Labeling
Culture Media
Rats
Demonstrations
Femur

Keywords

  • Bioreactor
  • Bone viability
  • Ex vivo
  • Flow perfusion
  • Lacunocanalicular flow

ASJC Scopus subject areas

  • Medicine (miscellaneous)
  • Biomaterials
  • Biomedical Engineering

Cite this

Flow perfusion maintains ex vivo bone viability : A novel model for bone biology research. / Davidson, Edward H.; Reformat, Derek D.; Allori, Alessandro; Canizares, Orlando; Janelle Wagner, I.; Saadeh, Pierre B.; Warren, Stephen M.

In: Journal of Tissue Engineering and Regenerative Medicine, Vol. 6, No. 10, 01.11.2012, p. 769-776.

Research output: Contribution to journalArticle

Davidson, EH, Reformat, DD, Allori, A, Canizares, O, Janelle Wagner, I, Saadeh, PB & Warren, SM 2012, 'Flow perfusion maintains ex vivo bone viability: A novel model for bone biology research', Journal of Tissue Engineering and Regenerative Medicine, vol. 6, no. 10, pp. 769-776. https://doi.org/10.1002/term.478
Davidson, Edward H. ; Reformat, Derek D. ; Allori, Alessandro ; Canizares, Orlando ; Janelle Wagner, I. ; Saadeh, Pierre B. ; Warren, Stephen M. / Flow perfusion maintains ex vivo bone viability : A novel model for bone biology research. In: Journal of Tissue Engineering and Regenerative Medicine. 2012 ; Vol. 6, No. 10. pp. 769-776.
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