Biocompatibility of subcutaneously implanted marine macromolecules cross-linked bio-composite scaffold for cartilage tissue engineering applications

There is an intense interest in developing innovative biomaterials which support the invasion and proliferation of living cells for potential applications in tissue engineering and regenerative medicine. Present study demonstrated the in vivo biocompatibility and toxicity of a macromolecules cross-linked biocomposite scaffold composed of hydroxyapatite, alginate, chitosan and fucoidan abbreviated as HACF. The in vivo biocompatibility and toxicity of HACF scaffold were tested by comparing them with those of a biocompatible surgical metal implant (SMI) in a subcutaneous rat model. Following the implantation, animals were sacrificed and the scaffolds were resected at 1st, 4th, and 8th weeks; the surrounding tissue along with the implant was removed to evaluate its biocompatibility. The effects of implanted biomaterial scaffolds on vital organ systems such as liver, kidney, etc., have been studied by hematology and serum biochemistry. The activities of pro-inflammatory marker enzymes such as COX, 5-LOX, 15-LOX, and NOS were normal in rats implanted with HACF scaffold. Hematological parameters, antioxidant and lipid peroxidation status were also found to be normal in implanted rats same as that of control and SMI. The modulatory effect of implanted scaffold over inflammatory and stress signaling cascades were confirmed by the normalized mRNA expressions of NF-B, TNF- and IL-6. The histopathological analysis of liver, kidney and tissue support our results. Taken together, these results demonstrated that HACF biocomposite scaffold signifies its suitability for further research as a scaffold material for cartilage tissue engineering applications.