title: Cell-extracellular matrix interactions regulate neural differentiation of human embryonic stem cells.
abstract: BACKGROUND
  Interactions of cells with the extracellular matrix (ECM) are critical for the establishment and maintenance of stem cell self-renewal and differentiation. However, the ECM is a complex mixture of matrix molecules; little is known about the role of ECM components in human embryonic stem cell (hESC) differentiation into neural progenitors and neurons.
  
  
  RESULTS
  A reproducible protocol was used to generate highly homogenous neural progenitors or a mixed population of neural progenitors and neurons from hESCs. This defined adherent culture system allowed us to examine the effect of ECM molecules on neural differentiation of hESCs. hESC-derived differentiating embryoid bodies were plated on Poly-D-Lysine (PDL), PDL/fibronectin, PDL/laminin, type I collagen and Matrigel, and cultured in neural differentiation medium. We found that the five substrates instructed neural progenitors followed by neuronal differentiation to differing degrees. Glia did not appear until 4 weeks later. Neural progenitor and neuronal generation and neurite outgrowth were significantly greater on laminin and laminin-rich Matrigel substrates than on other 3 substrates. Laminin stimulated hESC-derived neural progenitor expansion and neurite outgrowth in a dose-dependent manner. The laminin-induced neural progenitor expansion was partially blocked by the antibody against integrin alpha6 or beta1 subunit.
  
  
  CONCLUSIONS
  We defined laminin as a key ECM molecule to enhance neural progenitor generation, expansion and differentiation into neurons from hESCs. The cell-laminin interactions involve alpha6beta1 integrin receptors implicating a possible role of laminin/alpha6beta1 integrin signaling in directed neural differentiation of hESCs. Since laminin acts in concert with other ECM molecules in vivo, evaluating cellular responses to the composition of the ECM is essential to clarify further the role of cell-matrix interactions in neural derivation of hESCs.
authors.affiliation: Stem Cell Center, Developmental Biology, American Type Culture Collection, Manassas, VA, USA. wma@atcc.org
authors.forename: Wu
authors.initials: W
authors.lastname: Ma
authors.forename: Tara
authors.initials: T
authors.lastname: Tavakoli
authors.forename: Eric
authors.initials: E
authors.lastname: Derby
authors.forename: Yevgeniya
authors.initials: Y
authors.lastname: Serebryakova
authors.forename: Mahendra S
authors.initials: MS
authors.lastname: Rao
authors.forename: Mark P
authors.initials: MP
authors.lastname: Mattson
mesh_terms: D000818:Animals; D002450:Cell Communication / Q000502:physiology*; D002454:Cell Differentiation / Q000502:physiology*; D002460:Cell Line; D003094:Collagen; D004338:Drug Combinations; D053595:Embryonic Stem Cells / Q000166:cytology* / Q000502:physiology; D005109:Extracellular Matrix / Q000502:physiology*; D006801:Humans; D007797:Laminin; D051379:Mice; D016501:Neurites / Q000378:metabolism / Q000502:physiology; D009474:Neurons / Q000166:cytology* / Q000502:physiology; D011509:Proteoglycans; D013997:Time Factors
chemical_list: D004338:Drug Combinations; D007797:Laminin; D011509:Proteoglycans; C059485:matrigel; D003094:Collagen