In vitro and in vivo evaluation of (L)-lactide/ε-caprolactone copolymer scaffold to support myoblast growth and differentiation.

Skeletal muscle regeneration involves the activation of satellite cells to myoblasts, followed by their proliferation and fusion to form multinucleated myotubes and myofibers. The potential of in vitro proliferated myoblasts to treat various diseases and tissue defects can be exploited using tissue-engineering principles. With an aim to develop a biocompatible and biodegradable scaffold that supports myoblast growth and differentiation, we have developed a porous sponge with 70/30 L-lactide/ε-caprolactone copolymer (PLC) using a phase inversion combined with particulate leaching method. Degradation studies indicated that the sponge retained its structural integrity for 5 months in vitro and had undergone complete biodegradation within 9 months in vivo. The sponge supported human myoblasts attachment and its proliferation. Myoblasts seeded on the PLC sponge differentiated and fused in vitro to form myotubes expressing myosin heavy chain. Histological and molecular analyses of the PLC scaffolds seeded with green fluorescent protein-labeled human myoblasts and implanted ectopically under the skin in SCID mice demonstrated the presence of multinucleated myotubes expressing human muscle-specific markers. Our results suggest that PLC sponges loaded with myoblasts can be used for skeletal muscle engineering or for inducing muscle repair.

Defining Permissible Time Lapse between Umbilical Cord Tissue Collection and Commencement of Cell Isolation.

BACKGROUND: Umbilical cord tissue is a very rich source of mesenchymal stem cells. Instead of discarding this source we are banking the tissue along with cord blood for possible future cell based applications. The cord tissue needs to be transported and stored properly in order for it to be good enough for cell isolation at a later date. In this paper we have carried out a validation study to determine the maximum permissible time between cord tissue collection and beginning of cell culture process under defined conditions of temperature and collection media. METHODS: Ten cord tissue samples were used for this study. The umbilical cord tissue segments were transported and stored at 2 - 8°(C) for varying periods of time viz. 04, 11, 22 and 30 days in a defined medium after which MSCs were isolated and characterized by flow cytometry. Karyotypic studies were also performed on the isolated cells at the above time points. RESULTS: MSCs could be successfully isolated from 09 even samples after a storage period of 22 days and from 07 samples after a period of 30 days from the date of collection. There was no change in the morphology, immunophenotye, karyotypye and growth potential of the cells isolated from cord tissue after the maximum storage period of 30 days. CONCLUSION: The umbilical cord tissue is stable for as long as 22 days if stored at the recommended storage conditions of 2 - 8°(C) in the defined medium.