Short Laminin Peptide for Improved Neural Stem Cell Growth

Human neural stem/progenitor cells (hNSCs) are very difficult to culture and require human or animal source extracellular matrix molecules, such as laminin or collagen type IV, to support attachment and to regulate their survival and proliferation: These extracellular matrix molecules are difficult to purify from human or animal tissues, have high batch-to-batch variability, and may cause an immune response if used in clinical applications. Although several laminin- and collagen IV-derived peptides are commercially available, they do not support long-term hNSC attachment and growth. To solve this problem, we developed a novel peptide sequence with only 12 amino acids based on the Ile-Lys-Val-Ala-Val, or IKVAV, sequence: Ac-Cys-Cys-Arg-Arg-Ile-Lys-Val-Ala-Val-Trp-Leu-Cys. This short peptide sequence, similar to tissue-derived full laminin molecules, supported hNSCs to attach and proliferate to confluence for continuous passage and subculture. This short peptide also directed hNSCs to differentiate into neurons. When conjugated to poly(ethylene glycol) hydrogels, this short peptide benefited hNSC attachment and proliferation on the surface of hydrogels and promoted cell migration inside the hydrogels with maximum enhancement at a peptide density of 10 mu M. This novel short peptide shows great promise in artificial niche development for supporting hNSC culture in vitro and in vivo and for promoting hNSC transplantation in future clinical therapy.