In vivo biocompatibility evaluation of electrospun composite scaffolds by subcutaneous implantation in rat.

In vivo biocompatibility of nanofibrous poly-L-lactic acid (P), poly-L-lactic acid/gelatin (PG), poly-L-lactic acid/hydroxyapatite (PH), and poly-L-lactic acid/gelatin/hydroxyapatite (PGH) scaffolds, useful in regenerative medicine and drug delivery, was evaluated by subcutaneous implantation in both male and female rats (n = 5) for up to 90 days. The body weight of each animal in the study was evaluated on a weekly basis, and no significant difference was noticed. Total and differential leukocyte counts displayed no inflammatory reaction due to scaffold implantation. Gross observation and histology of necropsied vital organs exhibited normal morphology of cell types and tissue, denying any systemic adverse reaction on distal organs. Histology of subcutaneous tissue surrounding scaffolds was done to assess any local toxic effect of implants and found all scaffolds to be compatible and nontoxic. Moreover, no remnant of scaffolds was observed in any of the histological sections, suggesting all scaffolds to be biodegradable. All the results in this study confirm that nanofibrous scaffolds P, PG, PH, and PGH are biocompatible and safe for bone tissue engineering application.