Protein Adsorption Alters Hydrophobic Surfaces Used for Suspension Culture of Pluripotent Stem Cells.
This Letter examines the physical and chemical changes that occur at the interface of methyl-terminated alkanethiol self-assembled monolayers (SAMs) after exposure to cell culture media used to derive embryoid bodies (EBs) from pluripotent stem cells. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy analysis of the SAMs indicates that protein components within the EB cell culture medium preferentially adsorb at the hydrophobic interface. In addition, we examined the adsorption process using surface plasmon resonance and atomic force microscopy. These studies identify the formation of a porous, mat-like adsorbed protein film with an approximate thickness of 2.5 nm. Captive bubble contact angle analysis reveals a shift toward superhydrophilic wetting behavior at the cell culture interface due to adsorption of these proteins. These results show how EBs are able to remain in suspension when derived on hydrophobic materials, which carries implications for the rational design of suspension culture interfaces for lineage specific stem-cell differentiation.
†Department of Materials Science and Engineering, University of California, Los Angeles, 420 Westwood Plaza, Los Angeles, California 90095, United States.
Steven J
SJ
Jonas
§California NanoSystems Institute, University of California, Los Angeles, 570 Westwood Plaza, Los Angeles, California 90095, United States.|⊥WPI Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.
Adam Z
AZ
Stieg
†Department of Materials Science and Engineering, University of California, Los Angeles, 420 Westwood Plaza, Los Angeles, California 90095, United States.
Wade
W
Richardson
#Isis Pharmaceuticals, Inc., 2855 Gazelle Court, Carlsbad, California 92010, United States.
Shuling
S
Guo
‡Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, 615 Charles East Young Drive South, Los Angeles, California 90095, United States.
David N
DN
Powers
‡Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, 615 Charles East Young Drive South, Los Angeles, California 90095, United States.
James
J
Wohlschlegel
†Department of Materials Science and Engineering, University of California, Los Angeles, 420 Westwood Plaza, Los Angeles, California 90095, United States.|§California NanoSystems Institute, University of California, Los Angeles, 570 Westwood Plaza, Los Angeles, California 90095, United States.|∥Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA, University of California, Los Angeles, 615 Charles East Young Drive South, Los Angeles, California 90095, United States.
Bruce
B
Dunn
D000327:Adsorption; D018929:Cell Culture Techniques; D003470:Culture Media / Q000737:chemistry; D058732:Embryoid Bodies / Q000166:cytology; D039904:Pluripotent Stem Cells / Q000166:cytology*; D011506:Proteins / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000737:chemistry; D013499:Surface Properties; D013535:Suspensions; D017155:Wettability
D003470:Culture Media; D011506:Proteins; D013438:Sulfhydryl Compounds; D013535:Suspensions
biointerfaces; pluripotent stem cells; protein adsorption; self-assembled monolayers; wettability