Using poly(l‐lactic acid) and poly(ɛ‐caprolactone) blends to fabricate self‐expanding, watertight and biodegradable surgical patches for potential fetoscopic myelomeningocele repair

Abstract

Our study focuses on the development and characterization of a self-expanding, watertight and biodegradable patch for fetoscopic myelomeningocele (MMC) prenatal repair. We fabricated poly(l-lactic acid) (PLA) and poly(ɛ-caprolactone) (PCL) blend films by solution casting. Formulation c with average glass transition temperature of 37.6 ± 1.2°C was chosen for temporospatial recovery. Favorable results from surface studies reflected homogeneous dispersion of polymers in the blend. The cytotoxicity was studied in human foreskin fibroblasts. The blend film was cytocompatible, evidenced by matching percentage of live cells in exposed and control solutions. Subsequently, liquid water permeability experiments confirmed watertight nature of films. Finally, in vitro degradation was investigated in phosphate buffered saline (PBS) and amniotic fluid (AF) separately for 16 weeks. Similar weight loss (n = 6, p = 0.912) and significantly different (n = 3, p = 0.025) surface roughness was observed in PBS and AF, respectively, at 16 weeks. Functional group analysis displayed increasing carbonyl and hydroxyl bonds in PBS and AF, respectively, over time, indicating progression of hydrolytic degradation. Favorable characterization results provide strong evidence to employ PLA-PCL blend films as surgical patches in fetoscopic MMC repair. Designed patch serves as standalone system to successfully tackle impending hurdles of MMC repair and proves to be a superior alternative compared to existing patches. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2018.

Hydrogel and neural progenitor cell delivery supports organotypic fetal spinal cord development in an ex vivo model of prenatal spina bifida repair

“…[25][26][27] Accordingly, novel experimental approaches aimed at further improving neurologic outcomes in these children have been pursued by multiple laboratories worldwide. [28][29][30] In this study, we developed an injectable hydrogel patch containing human neural progenitor cells as proof of concept for a cell-based tissue engineering strategy for fetal MMC repair. The immature human neural progenitors generated using transgene-free reprogramming methods stained positive for nestin, remained mostly viable within 3D scaffolds for over 24 h, and expressed genes associated with neurotrophic activity.…”

“…This bi-layered approach could also serve an important barrier function to further minimize mechanical trauma. 30,82 Continued advances in the evaluation of these biomaterials may eventually enable more widespread adoption of fetoscopic repair of MMC defects, which remains technically demanding compared to open surgery but has been shown to induce less maternal-fetal morbidity. 83,84 Moving forward, we propose that our slice culture model could be used as a unique "disease-in-dish" approach to understand mechanisms of mechanical and chemical spinal cord injury in MMC.…”

“… 25 – 27 Accordingly, novel experimental approaches aimed at further improving neurologic outcomes in these children have been pursued by multiple laboratories worldwide. 28 – 30 …”

Study of thermomechanical, structural and antibacterial properties of poly(lactic acid) reinforced with graphene oxide nanoparticles via melt mixing

“…Lately, Tatu et al . fabricated PLLA and poly( ε ‐caprolactone) blend films by solution casting to be used as a self‐expanding, watertight and biodegradable patches for fetoscopic myelomeningocele prenatal repair 2 . The most critical characteristics for further limiting the applications of PLLA are the relatively low crystallinity, slow crystallization rate, insufficient mechanical strength in load‐bearing applications, relatively slow degradation rate into natural metabolites of the human body, inherently hydrophobic nature in vivo and lack of bioactivity for biomineral growth 2 .…”

“…1 Lately, Tatu et al fabricated PLLA and poly(ε-caprolactone) blend films by solution casting to be used as a self-expanding, watertight and biodegradable patches for fetoscopic myelomeningocele prenatal repair. 2 The most critical characteristics for further limiting the applications of PLLA are the relatively low crystallinity, slow crystallization rate, insufficient mechanical strength in load-bearing applications, relatively slow degradation rate into natural metabolites of the human body, inherently hydrophobic nature in vivo and lack of bioactivity for biomineral growth. 2 Being a thermoplastic aliphatic semicrystalline polyester, PLLA can be engineered using various methods, such as addition of nanofillers, blending and/or copolymerization, so as to overcome these challenges by tuning its degree of crystallinity and thermal and mechanical properties, thus obtaining the appropriate properties on demand for each application.…”