Small Intestinal Submucosa versus Salt-Extracted Polyglycolic Acid-Poly-L-lactic Acid: A Comparison of Neocartilage Formed in Two Scaffold Materials

Abstract

This study sought to compare differences in neocartilage produced over time from two types of resorbable scaffold materials. One material was entirely synthetic and contained a polyglycolic acid-poly-L-lactic acid matrix (PGA-PLLA). The second scaffold material was bioactive and consisted of a four-layered construct of porcine small intestinal submucosa (SIS). Disk-shaped scaffolds were seeded with canine chondrocytes and implanted into athymic mice for periods of 5, 8, 12, and 24 weeks. Constructs were examined microscopically, assayed for hydroxyproline (HP) and glycosaminoglycan (GAG) content, and collagen typed (I or II) at each time period. Creep indentation tests determined aggregate and shear modulus, permeability, and thickness. Results indicated that SIS maintained its thickness through the first 12 weeks, and then doubled by week 24. The 24-week tissue appeared chondroid-like and possessed high GAG content. Tissues derived from PGA-PLLA scaffolds were lower in HP content than SIS-derived tissues, but type II collagen was demonstrated only in PGA-PLLA-derived tissues at 24 weeks. Mechanical properties were not significantly different for any tissue over time (p > 0.05), but aggregate and shear modulus mean values were consistently higher for PGA-PLLA-derived tissues at nearly every time interval. This, coupled with the presence of collagen types I and II, suggested a more congruent solid phase may be forming within the extracellular matrix of tissues derived from PGA-PLLA scaffolds. Future study is necessary to compare these materials under simulated loading conditions.

SIS with tissue-cultured allogenic cartilages patch tracheoplasty in a rabbit model for tracheal defect

“…In our previous studies, we verified that our preparation of rabbit SIS had good biocompatibility with cartilage cells, which was consistent with the results reported for Surgisis by Beatty [10]. In this study, we evaluated the efficacy of rabbit SIS (prepared in our laboratory) compounded with tissue-cultured allogenic cartilages in the patch repair of a rabbit critical-sized tracheal defect.…”

Development and Characterization of Acellular Extracellular Matrix Scaffolds from Porcine Menisci for Use in Cartilage Tissue Engineering

“…Despite promising clinical results of these scaffolds, ECM scaffold derived from tissue could additionally provide biophysical and biochemical cues to modulate the neo-tissue formation by mimicking the functional and structural characteristics of the native environment, and regulating cellular functions through various existing bioactive molecules, such as the ECM, growth factors, and cytokines. 19,20 For example, Beatty et al 21 seeded chondrocytes in polyglycolic acid-poly-l-lactic acid matrix (PGA-PLLA) scaffolds or ECM-derived scaffolds from porcine small intestinal submucosa (SIS), and implanted them into athymic mice. Higher GAG content and chondroid-like tissues appeared in the SIS group, demonstrating the biological activity of ECM scaffold.…”

Award Winner in the Young Investigator Category, 2014 Society for Biomaterials Annual Meeting and Exposition, Denver, Colorado, April 16–19, 2014: Periodically perforated core–shell collagen biomaterials balance cell infiltration, bioactivity, and mechanical properties

“…36 Briefly, scaffold pieces were rinsed in PBS to remove dead or unattached cells and then digested in a papain solution at 60°C for 24 h. Fluorescence was read on a standard microplate reader (360/465 nm excitation/emission, Tecan, Switzerland). All results were interpolated on a standard curve created with a known number of tenocytes and normalized to the original number of tenocytes seeded.…”