title: Keratin mediated attachment of stem cells to augment cardiomyogenic lineage commitment.
abstract: The objective of this work was to develop a simple surface modification technique using keratin derived from human hair for efficient cardiomyogenic lineage commitment of human mesenchymal stem cells (hMSCs). Keratin was extracted from discarded human hair containing both the acidic and basic components along with the heterodimers. The extracted keratin was adsorbed to conventional tissue culture polystyrene surfaces at different concentration. Keratin solution of 500μg/ml yielded a well coated layer of 12±1nm thickness with minimal agglomeration. The keratin coated surfaces promoted cell attachment and proliferation. Large increases in the mRNA expression of known cardiomyocyte genes such as cardiac actinin, cardiac troponin and β-myosin heavy chain were observed. Immunostaining revealed increased expression of sarcomeric α-actinin and tropomyosin whereas Western blots confirmed higher expression of tropomyosin and myocyte enhancer factor 2C in cells on the keratin coated surface than on the non-coated surface. Keratin promoted DNA demethylation of the Atp2a2 and Nkx2.5 genes thereby elucidating the importance of epigenetic changes as a possible molecular mechanism underlying the increased differentiation. A global gene expression analysis revealed a significant alteration in the expression of genes involved in pathways associated in cardiomyogenic commitment including cytokine and chemokine signaling, cell-cell and cell-matrix interactions, Wnt signaling, MAPK signaling, TGF-β signaling and FGF signaling pathways among others. Thus, adsorption of keratin offers a facile and affordable yet potent route for inducing cardiomyogenic lineage commitment of stem cells with important implications in developing xeno-free strategies in cardiovascular regenerative medicine.
authors.affiliation: Department of Materials Engineering and Indian Institute of Science, Bangalore 560012 India.
authors.forename: Lopamudra Das
authors.initials: LD
authors.lastname: Ghosh
authors.affiliation: Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012 India.
authors.forename: Venkatraman
authors.initials: V
authors.lastname: Ravi
authors.affiliation: Department of Materials Engineering and Indian Institute of Science, Bangalore 560012 India.
authors.forename: Pallab
authors.initials: P
authors.lastname: Sanpui
authors.affiliation: Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012 India.
authors.forename: Nagalingam R
authors.initials: NR
authors.lastname: Sundaresan
authors.affiliation: Department of Materials Engineering and Indian Institute of Science, Bangalore 560012 India. Electronic address: kchatterjee@materials.iisc.ernet.in.
authors.forename: Kaushik
authors.initials: K
authors.lastname: Chatterjee
mesh_terms: D000327:Adsorption; D000818:Animals; D002448:Cell Adhesion; D019070:Cell Lineage; D002470:Cell Survival; D018899:CpG Islands; D019175:DNA Methylation; D005109:Extracellular Matrix / Q000378:metabolism; D005260:Female; D005346:Fibroblast Growth Factors / Q000378:metabolism; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006197:Hair / Q000737:chemistry*; D000072576:Homeobox Protein Nkx-2.5 / Q000378:metabolism; D006801:Humans; D007633:Keratins / Q000737:chemistry*; D020935:MAP Kinase Signaling System; D064326:MEF2 Transcription Factors / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D032383:Myocytes, Cardiac / Q000166:cytology*; D010641:Phenotype; D011137:Polystyrenes / Q000737:chemistry; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology*; D013499:Surface Properties; D016212:Transforming Growth Factor beta / Q000378:metabolism; D024723:Ventricular Myosins / Q000737:chemistry
chemical_list: D000072576:Homeobox Protein Nkx-2.5; D064326:MEF2 Transcription Factors; C578040:MEF2C protein, human; C095552:NKX2-5 protein, human; D011137:Polystyrenes; D016212:Transforming Growth Factor beta; D005346:Fibroblast Growth Factors; D007633:Keratins; D024723:Ventricular Myosins; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases; C506946:ATP2A2 protein, human
keywords: Cardiomyocyte; Cardiovascular diseases; Keratin; Regenerative medicine; Stem cells; Surface engineering