In Vivo Evaluation of Novel PLA/PCL Polymeric Patch in Rats for Potential Spina Bifida Coverage

Current therapeutic materials for spina bifida repair showed a limited number of options in the market, and none of them have all the requirements as the ideal patch. In fact, sometimes the surgical procedures pose substantial challenges using different patches to fully cover the spina bifida lesion. For this purpose, a tailored patch made of poly (L-lactic acid) and poly (ε-caprolactone) blend was designed and validated in vitro to accomplish all these requirements but was never tested in vivo.

In our present study, the designed patch was analyzed in terms of rejection from the animal when implanted subcutaneously and as a dural substitute in the spinal cord. Inflammatory reaction (Iba1), astrogliosis (GFAP), was analyzed and functional interaction with spinal cord tissue assessing the (%motor-evoked potentials /compound motor action potential) by electrophysiology.

No evidence of adverse or inflammatory reactions was observed in both models of subcutaneous implantation, neither in the neural tissue as a dural substitute. No signs of astrogliosis in the neural tissue were observed, and no functional alteration with improvement of the motor-evoked potential's amplitude was detected after 4 wk of implantation as a dural substitute in the rat spinal cord.

Designed patch used as a dural substitute will apparently not produce inflammation, scar formation, or tethering cord and not induce any adverse effect on regular functions of the spinal cord. Further studies are needed to evaluate potential improvements of this novel polymeric patch in the spinal cord regeneration using spina bifida models.