Enhanced cell adhesion and mature intracellular structure promoted by squaramide-based RGD mimics on bioinert surfaces

Sri Kamesh Narasimhan, Preeti Sejwal, Shifa Zhu, Yan Yeung Luk

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

Highly selective molecular binding and the subsequent dynamic protein assemblies control the adhesion of mammalian cells. Molecules that inhibit cell adhesion have the therapeutic potential for a wide range of diseases. Here, we report an efficient synthesis (2-4 steps) of a class of squaramide molecules that mimics the natural tripeptide ligand Arg-Gly-Asp (RGD) that mediates mammalian cell adhesion through binding with membrane protein integrin. In solution, this class of squaramides exhibits a higher potency at inhibiting mammalian cell adhesion than RGD tripeptides. When immobilized on a bio-inert background formed by self-assembled monolayers of alkanethiols on gold films, squaramide ligands mediate vastly different intracellular structures than RGD ligands. Immunostaining revealed that the focal adhesions are smaller, but with a larger quantity, for cells adhered on squaramides than that on RGD ligands. Furthermore, the actin filaments are also more fibrous and well distributed for cell adhesion mediated by squaramide than that by RGD ligands. Quantification reveal that squaramide ligands mediate about 1.5 times more total focal adhesion (measured by the summation of the area of all focal adhesions) than that by natural RGD ligands. This result suggests that cell adhesion inhibitors, while blocking the attachment of cells to surfaces, may induce more focal adhesion proteins. Finally, this work demonstrates that immobilizing new ligands on bioinert surfaces provide a powerful tool to study mammalian cell adhesion.

Original languageEnglish (US)
Pages (from-to)2210-2216
Number of pages7
JournalBioorganic and Medicinal Chemistry
Volume21
Issue number8
DOIs
StatePublished - Apr 15 2013

Fingerprint

Cell adhesion
Cell Adhesion
Ligands
Focal Adhesions
Adhesion
Molecules
squaramide
Cell Adhesion Molecules
Self assembled monolayers
Actin Cytoskeleton
Integrins
Gold
Actins
Membrane Proteins
Proteins
Cells

Keywords

  • Bioinert surfaces
  • Focal adhesion
  • RGD mimics
  • Self-assembled monolayers
  • Squaramide

ASJC Scopus subject areas

  • Pharmaceutical Science
  • Drug Discovery
  • Organic Chemistry
  • Molecular Medicine
  • Molecular Biology
  • Clinical Biochemistry
  • Biochemistry

Cite this

Enhanced cell adhesion and mature intracellular structure promoted by squaramide-based RGD mimics on bioinert surfaces. / Narasimhan, Sri Kamesh; Sejwal, Preeti; Zhu, Shifa; Luk, Yan Yeung.

In: Bioorganic and Medicinal Chemistry, Vol. 21, No. 8, 15.04.2013, p. 2210-2216.

Research output: Contribution to journalArticle

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