Inhibition of apoptosis in human induced pluripotent stem cells during expansion in a defined culture using angiopoietin-1 derived peptide QHREDGS

Biomaterials. 2014 Sep;35(27):7786-99. doi: 10.1016/j.biomaterials.2014.05.018. Epub 2014 Jun 13.

Abstract

Adhesion molecule signaling is critical to human pluripotent stem cell (hPSC) survival, self-renewal, and differentiation. Thus, hPSCs are grown as clumps of cells on feeder cell layers or poorly defined extracellular matrices such as Matrigel. We sought to define a small molecule that would initiate adhesion-based signaling to serve as a basis for a defined substrate for hPSC culture. Soluble angiopoeitin-1 (Ang-1)-derived peptide QHREDGS added to defined serum-free media increased hPSC colony cell number and size during long- and short-term culture when grown on feeder cell layers or Matrigel, i.e. on standard substrates, without affecting hPSC morphology, growth rate or the ability to differentiate into multiple lineages both in vitro and in vivo. Importantly, QHREDGS treatment decreased hPSC apoptosis during routine passaging and single-cell dissociation. Mechanistically, the interaction of QHREDGS with β1-integrins increased expression of integrin-linked kinase (ILK), increased expression and activation of extracellular signal-regulated kinases 1/2 (ERK1/2), and decreased caspase-3/7 activity. QHREDGS immobilization to polyethylene glycol hydrogels significantly increased cell adhesion in a dose-dependent manner. We propose QHREDGS as a small molecule inhibitor of hPSC apoptosis and the basis of an affordable defined substrate for hPSC maintenance.

Keywords: Adhesion; Angiopoietin-1; Apoptosis; Human pluripotent stem cells; Integrins; QHREDGS.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angiopoietin-1 / pharmacology*
  • Animals
  • Apoptosis / drug effects*
  • Caspases / metabolism
  • Cell Adhesion / drug effects
  • Cell Count
  • Cell Culture Techniques / methods*
  • Cell Proliferation / drug effects
  • Cell Size / drug effects
  • Cell Survival / drug effects
  • Cells, Cultured
  • Enzyme Activation / drug effects
  • Extracellular Signal-Regulated MAP Kinases / metabolism
  • Feeder Cells / cytology
  • Feeder Cells / drug effects
  • Humans
  • Induced Pluripotent Stem Cells / cytology*
  • Induced Pluripotent Stem Cells / drug effects
  • Induced Pluripotent Stem Cells / enzymology
  • Integrin beta1 / metabolism
  • Mice
  • Peptides / pharmacology*
  • Protein Serine-Threonine Kinases / metabolism
  • Time Factors

Substances

  • Angiopoietin-1
  • Integrin beta1
  • Peptides
  • integrin-linked kinase
  • Protein Serine-Threonine Kinases
  • Extracellular Signal-Regulated MAP Kinases
  • Caspases