Tiam Mana Saffari

225 MICRO CT ANALYSIS AFTER STEM CELL DELIVERY AND ANGIOGENESIS 10 Spatial distribution of blood vessels Control, autograft and allograft nerves The vessels were distributed per volume, to describe a vessel segment volume prior to sprouting into a new segment and per percentage to denote the lumen diameter distribution, respectively. The relation of the volume to the diameter within blood vessels was distributed in a linear matter (Figure 4A). The greatest volume measured 0.55±0.07mm 3 for autografts, 0.21±0.07 mm 3 for allografts and 0.46±0.05 mm 3 for controls, respectively (4A). For allografts, most of these vessels were 0-20 µm (48%) and these vessel counts decreased as diameters increased. For autografts, the majority of vessels were between 20-80 µm (21% for 20-40 µm, 22% for 40-60 µm and 20% for 60-80 µm). A similar bell-shaped pattern was observed in controls, where most vessels were distributed between 20-100 µm (16% for 20-40 µm, 20% for 40-60 µm, 22% for 60-80 µm and 17% for 80-100 µm) (Figure 4B). Allograft, SIEF and SIEF nerves combined with stem cells The volume of vessels was largely increased when allografts were wrapped within a SIEF flap and further increased when combined with stem cells. Largest volume of vessels and diameter were found when SIEF was combined with undifferentiated MSCs (1.30±0.23 mm 3 , Figure 5A). The greatest measured volume for SIEF combined with differentiated MSCs was 0.79±0.12 mm 3 and 0.52±0.06 mm 3 for SIEF, respectively (Figure 5A). Addition of the SIEF f lap resulted in an increased vessel diameter compared to allograft only, resulting in 18% of vessels being between 20-40 µm and the vessels to be more uniformly distributed with regard to diameter (Figure 5B). This increase in vessel diameter was more prominently visible in nerve allografts that received both surgical angiogenesis and stem cell delivery; resulting in the distribution to be skewed to the right (i.e. larger vessels). Blood vessels in the differentiated MSCs and SIEF group combined, showed little percentage of small vessels (2% for 0-20 µm) with a peak of 18% for 40-60 µm and broad distribution towards 300 µm. When undifferentiated MSCs were combined with the SIEF flap, it resulted in the broadest distribution of vessels compared to all other groups, with majority of vessels to be distributed between 0-140 µm (5B).