Figure 2.
Effects of SAPs on in vitro differentiation of neural stem cells (A and B) and in vivo repair of neural tissues (C and D). A. (a) Neuronal density (green) is selectively increased relative to astrocytes (red) by soft (7.3 ± 0.9 kPa storage modulus) vs stiff (22.9 ± 5 kPa) PA substrate (DAPI stain) in hippocampal culture. (b) Comparison of cell densities (n = 3, p<0.001).25 Reprinted with permission from ref. 25. B. Left: IKVAV-PA gels enable statistically significant growth of neurons relative to laminin and poly-D-lysine (PDL) controls at one and seven days (P<0.5, P<0.01 in duplicate). Right: Increased concentrations of IKVAV-PA, but not IKVAV peptide, increases one-day neuronal differentiation. IKVAV-PA and EQS-PA (solid line) and EQS-PA combined with varied amounts of soluble IKVAV peptide (dashed line).28 Reprinted with permission from ref. 28. C. IKVAV-PA injection reduces the normalized cortical and hippocampal area of amyloid-beta plaques (Green, thioflavin S stain) in a murine model of Alzeheimer’s Disease relative to vehicle control (P<0.05).33 Reprinted with permission from ref. 33. D. Left: Neurolucida tracing of regenerating murine BDA-labeled corticospinal tract motor neurons 11 weeks post-SCI. IKVAV-PA presence results in greatly increased migration into the lesion. Right: This regrowth corresponds to statistically significant improvement of motor function after five weeks as quantified by BBB score.36 Reprinted with permission from ref. 36.