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D Lickorish

Publications and source records attributed to D Lickorish.

2 recordsLinked to original sources

A three-phase, fully resorbable, polyester/calcium phosphate scaffold for bone tissue engineering: Evolution of scaffold design.

Bone tissue engineering strategies are fundamentally based upon porous scaffold materials that serve as a support for ingrowth of host cells and/or provide a substrate for exogenously delivered cells. Here we report the application of a surface calcium phosphate (CaP) mineral layer to a macroporous polymeric/CaP composite biomaterial, with a macroporous interconnectivity, and its subsequent in vivo evaluation in a rodent femoral defect. The application of the mineral layer eliminates the fibrous tissue encapsulation and foreign body giant cell response commonly seen at the interface of polymeric materials, yet retains the unique characteristics of the parent material as being macroporous, completely biodegradable and possessing a high degree of interconnectivity. This represents the third generation of this scaffold material, incorporating iterative changes to the scaffold design in response to both materials and biological design criteria to produce a material with enhanced in vitro and in vivo performance.

Absorbable Implants↗

An in-vivo model to interrogate the transition from acute to chronic inflammation.

This study describes the modulation of the rodent foreign body giant cell (FBGC) response to subcutaneously implanted, biodegradable poly(lactide-co-glycolide)/calcium phosphate (PLGA/CaP) composites by application of a thin surface coat of calcium phosphate. Macroporous PLGA/CaP composite scaffolds, with interconnecting macroporosity, were half coated with a 3mm thick layer of CaP by immersion in simulated body fluid. Half-coated scaffolds were implanted subcutaneously in the dorsum of male Wistar rats for 1, 4 and 8 weeks. Specimens were embedded in paraffin and tissue sections evaluated by light microscopy with particular reference to the FBGC response. Histomorphometry revealed that FBGCs were in contact with 6% (+/- 3.5%) of the uncoated half, at 1 week, but no FBGCs were seen on the coated half. By 4 weeks, FBGCs were seen on both the uncoated and coated halves of the scaffolds with 87% (+/-10%) and 36% (+/-4%) FBGC/polymer contact respectively. By 8 weeks these FBGC contact percentages had risen to 97% (+/-0.45%) in the case of the uncoated halves of scaffolds, but decreased to 22% (+/-4%) in the case of the CaP-coated halves. Thus the CaP coating abrogated the FBGC response to the underlying polymer. Such a model may prove useful in providing an experimental system whereby both the mechanisms of biocompatibility and the transition from acute to chronic inflammation could be interrogated.

Absorbable Implants↗