FIG. 8.

Comparable cellular infiltration in juvenile and adult meniscus defects repaired with nanofibrous scaffolds. (A) Cylindrical meniscus explants were formed, and a central core was removed and replaced with a column of electrospun poly(ɛ-caprolactone) nanofibrous scaffold disks welded together at the central point. (B) Cell infiltration into the cylindrical constructs was quantified using a custom MATLAB program. Left: Excerpt of image of the DAPI-stained composite with the electrospun scaffold (ES) region divided to quantify cell infiltration from the surrounding native tissue (NT). Right: Cells were counted in binary images by zone. Native tissue density was determined using three regions from each image (boxes) and averaged across all samples. (C) Left: DAPI staining of integration zone between native tissue (NT) and scaffold (Sc). Scale bar = 100 μm. Right: H&E staining of integration zone. (D) Significant cell infiltration was seen after 3 and 6 weeks for juvenile and adult meniscus defects, respectively. By week 6, scaffold infiltration was comparable between ages (n = 9/age/timepoint). (E) Juvenile cells populated the scaffold more rapidly than adult scaffolds, although the overall densities were comparable despite a significantly higher starting density in juvenile native tissue. *Significant difference (p < 0.05) from week 1. ^#Significant difference (p < 0.05) between ages. ^αSignificant difference (p < 0.05) from zone 1. Color images available online at www.liebertonline.com/ten.