Compositional dependence of hematopoietic stem cells expansion on bioceramic composite scaffolds for bone tissue engineering.

Abstract

Bioceramics are although well known for their osteoinductive and osseointegrative properties in bone tissue regeneration, yet, they are inappropriate for load bearing applications due to inadequate mechanical strength. In this article, the authors report the expansion of hematopoietic stem cells (HSCs) on as-synthesized composite scaffolds from hydroxyapatite and β-tricalcium phosphate for bone tissue engineering, in an adequate load-bearing application. The physical, structural, and mechanical properties of the composite scaffolds have been examined and correlated with the in vitro adhesion pattern of HSCs. The results indicated that the response of HSCs varies with change in the stoichiometry of composite scaffolds. The H2T2 scaffolds have exhibited the highest expansion of CD34+ cells and long-term culture initiating cells when compared with other stoichiometries. The results suggest that H2T2 composite can be a potential strategic bone-graft substitute in contrast with monolithic bioceramics, serving a dual role of bioresorbability and enhanced load-bearing capacity.