Journal: ACS Applied Materials & Interfaces

Article Title: Prechondrogenic ATDC5 Cell Attachment and Differentiation on Graphene Foam; Modulation by Surface Functionalization with Fibronectin

doi: 10.1021/acsami.9b14670

Figure Lengend Snippet: ATDC5 cells adhere more extensively to fibronectin, collagen I, and collagen IV. ATDC5 cells were screened with extracellular matrix array printed with collagen I (COL I), collagen III (COL III), collagen IV (COL IV), collagen V (COL V), collagen VI (COL VI), fibronectin (FN), vitronectin (VTN), laminin (LMN), tropoelastin (TE), and BSA as a negative control. (A) Representative bright-field images of ATDC5 cells incubated for 30 h indicated differential binding of a number of extracellular proteins. Scale bar: 40 μm. (B) Attached cell counts determined for each of the nine replicates, as well as mean and standard deviation are shown ( n = 9).

Article Snippet: Bovine fibronectin protein solution was obtained from R & D Systems (Biotechne Corporation, Minneapolis, MN, U.S.A.) and diluted to a concentration of 100 μg/mL in Ca 2+ - and Mg 2+ -free phosphate-buffered saline (PBS).

Techniques: Negative Control, Incubation, Binding Assay, Standard Deviation

Journal: ACS Applied Materials & Interfaces

Article Title: Prechondrogenic ATDC5 Cell Attachment and Differentiation on Graphene Foam; Modulation by Surface Functionalization with Fibronectin

doi: 10.1021/acsami.9b14670

Figure Lengend Snippet: Fibronectin interaction with graphene is stabilized by arginine residues. (A) Graphical rendering of the stabilized fibronectin atop the three graphene sheets with the four best arginine binders highlighted (Arg1166, Arg1369, Arg1374, Arg1403). The time evolution of the binding energy of these arginine residues with graphene is shown in the lower panel, color-coded for the amino acid residues. (B) Analogous to A but showing the data for the second studied configuration. This configuration features five arginine residue binders (Arg1166, Arg1351, Arg1379, Arg1445, Arg1493). (C) Binding energy with graphene computed for every amino acid with average binding energy above 1 kcal/mol, averaged over the 400 ns simulation. (D) Analogous to C, for the second studied configuration. The residue numbers are indicated, while the corresponding amino acid types are color-coded for both panels (C and D). (E and F) Time evolution of the fibronectin and arginine interaction energy with graphene for the two configurations. The lower plots in both panels show the fraction of arginine residue binding energy with respect to the total fibronectin-binding energy as a function of simulation time.

Article Snippet: Bovine fibronectin protein solution was obtained from R & D Systems (Biotechne Corporation, Minneapolis, MN, U.S.A.) and diluted to a concentration of 100 μg/mL in Ca 2+ - and Mg 2+ -free phosphate-buffered saline (PBS).

Techniques: Binding Assay, Residue

Journal: ACS Applied Materials & Interfaces

Article Title: Prechondrogenic ATDC5 Cell Attachment and Differentiation on Graphene Foam; Modulation by Surface Functionalization with Fibronectin

doi: 10.1021/acsami.9b14670

Figure Lengend Snippet: Mechanical properties. The measured quasi-static (A and B) and dynamic (C – E) properties of GF (hatched bars), GF coated in fibronectin (dark blue bars), and GF coated in fibronectin and cultured with ATDC5 cells (light blue bars) for 28 days. Fibronectin changed the elasticity of the composite (i.e., modulus values), but did not increase the viscoelastic properties (stress relaxation and phase shift).

Article Snippet: Bovine fibronectin protein solution was obtained from R & D Systems (Biotechne Corporation, Minneapolis, MN, U.S.A.) and diluted to a concentration of 100 μg/mL in Ca 2+ - and Mg 2+ -free phosphate-buffered saline (PBS).

Techniques: Cell Culture

Journal: ACS Applied Materials & Interfaces

Article Title: Prechondrogenic ATDC5 Cell Attachment and Differentiation on Graphene Foam; Modulation by Surface Functionalization with Fibronectin

doi: 10.1021/acsami.9b14670

Figure Lengend Snippet: Actin cytoskeleton of cells on GF and fibronectin-coated GF. Fluorescence of ATDC5 cells grown on glass-bottom tissue culture wells compared to GF, with or without fibronectin. Cell nuclei are stained blue (DAPI); Green, F-actin (Alexa Fluor 488 phalloidin); (A–D) ATDC5 cells were grown on glass-bottom tissue culture wells without (A and E) and with fibronectin (B and F); ATDC5 cells were grown on GF without (C and G) and with fibronectin (D and H). Note the prevalence of stress fibers and the absence of puncta in F and H compared to E and G, respectively. Additionally, note the relative abundance of puncta of actin which are more prevalent in the absence of fibronectin on glass-bottomed tissue culture wells as well as on GF. (A–D) Scale-bar: 50 μm. (E–H) Scale-bar: 10 μm.

Article Snippet: Bovine fibronectin protein solution was obtained from R & D Systems (Biotechne Corporation, Minneapolis, MN, U.S.A.) and diluted to a concentration of 100 μg/mL in Ca 2+ - and Mg 2+ -free phosphate-buffered saline (PBS).

Techniques: Fluorescence, Staining

Journal: ACS Applied Materials & Interfaces

Article Title: Prechondrogenic ATDC5 Cell Attachment and Differentiation on Graphene Foam; Modulation by Surface Functionalization with Fibronectin

doi: 10.1021/acsami.9b14670

Figure Lengend Snippet: ActB and Hsp90ab1 housekeeping genes. ActB and Hsp90ab1 are stably expressed by ATDC5 cells under all experimental conditions used in this study (i.e., on glass-bottom tissue culture wells, GF, and fibronectin-GF). (A) ActB and Hsp90ab1 cycle threshold levels were most consistent among all samples analyzed by qRT-PCR for candidate HKGs considered, based on pairwise analysis of variance for differences between threshold values, variance equal to 0.12. (B) Correlation analysis of cycle threshold values for Hsp90ab1 and ActB indicate a slope and an R 2 value close to 1. ( n = 15).

Article Snippet: Bovine fibronectin protein solution was obtained from R & D Systems (Biotechne Corporation, Minneapolis, MN, U.S.A.) and diluted to a concentration of 100 μg/mL in Ca 2+ - and Mg 2+ -free phosphate-buffered saline (PBS).

Techniques: Stable Transfection, Quantitative RT-PCR

Journal: ACS Applied Materials & Interfaces

Article Title: Prechondrogenic ATDC5 Cell Attachment and Differentiation on Graphene Foam; Modulation by Surface Functionalization with Fibronectin

doi: 10.1021/acsami.9b14670

Figure Lengend Snippet: GF supports or enhances gene expression levels. The effect of fibronectin, GF, and fibronectin in combination with GF on ATDC5 cell gene expression was investigated. Correlation analysis of relative expression levels was carried out to detect differential gene expression as a function of the cell culture substrate. The mRNA levels were compared for cells seeded on four distinct surfaces. Data points above the diagonal line indicate genes that are upregulated and data points below the diagonal line indicate genes that are downregulated. Data points falling on the diagonal line are not differentially expressed in experimental compared to control conditions. The effect of GF on gene expression is demonstrated in panels A and B. The effect of fibronectin on gene expression is demonstrated in panels C and D. (A) Relative gene expression levels in 2D cell culture conditions compared to cells grown in 3D on GF in the absence of fibronectin. (B) Relative gene expression levels in 2D cell culture conditions compared to cells grown in 3D on GF in the presence of fibronectin. (C) Relative gene expression levels in 2D cell culture conditions comparing the presence and absence of fibronectin. (D) Relative gene expression levels by cells grown in 3D on GF comparing the presence and absence of fibronectin. Genes for which expression levels met or exceeded the control are indicated in magenta, while those genes that were supported by substrate conditions are indicated by turquoise. Col2a1, a marker for chondrocyte differentiation, is shown as a diamond shape and bolded in each frame. Col2a1 is found above the diagonal line in A and B indicating upregulation as a function of 3D GF culture, and below the line in C and D, indicating downregulation as a function of fibronectin in either 2D or 3D culture. Genes included in this analysis are listed in Tables – .

Article Snippet: Bovine fibronectin protein solution was obtained from R & D Systems (Biotechne Corporation, Minneapolis, MN, U.S.A.) and diluted to a concentration of 100 μg/mL in Ca 2+ - and Mg 2+ -free phosphate-buffered saline (PBS).

Techniques: Gene Expression, Expressing, Cell Culture, Control, Marker

Journal: ACS Applied Materials & Interfaces

Article Title: Prechondrogenic ATDC5 Cell Attachment and Differentiation on Graphene Foam; Modulation by Surface Functionalization with Fibronectin

doi: 10.1021/acsami.9b14670

Figure Lengend Snippet: Expression of genes encoding mediators of cell attachment by ATDC5 cells on glass-bottom tissue culture wells, GF, and fibronectin-GF. (A) Time course of gene expression during chondrogenic differentiation for Ctnnal (triangle) and Ctnnb1 (circle). (B) Relative gene expression levels of Ctnnal (gray) and Ctnnb1 (black) at day 17 of chondrogenic differentiation in control 2D culture, 2D culture in the presence of fibronectin, 3D-GF, and 3D-GF coated with fibronectin. (C) Time course of gene expression during chondrogenic differentiation for Cd44 (triangle), Ncam1 (circle), and Sgce (square). (D) Relative gene expression levels of Cd44 (gray), Ncam1 (black), and Sgce (white) at day 17 in control 2D culture, 2D culture in the presence of fibronectin, 3D-GF, and 3D-GF coated with fibronectin. (E) Time course of gene expression during chondrogenic differentiation for Itga3 (triangle), Itga5 (circle), and Itgav (square). (F) Relative gene expression levels of Itga3 (gray), Itga5 (black ) , and Itgav (white) at day 17 in control 2D culture, 2D culture in the presence of fibronectin, 3D-GF, and 3D-GF coated with fibronectin. (G) Time course of gene expression during chondrogenic differentiation for Itgb1 . (H) Relative gene expression levels of Itgb1 at day 17 in control 2D culture, 2D culture in the presence of fibronectin, 3D-GF, and 3D-GF coated with fibronectin. Error bars = Mean ± SD. These genes are listed in Table with references from current literature indicating an association with chondrocyte differentiation.

Article Snippet: Bovine fibronectin protein solution was obtained from R & D Systems (Biotechne Corporation, Minneapolis, MN, U.S.A.) and diluted to a concentration of 100 μg/mL in Ca 2+ - and Mg 2+ -free phosphate-buffered saline (PBS).

Techniques: Expressing, Cell Attachment Assay, Gene Expression, Control

Journal: ACS Applied Materials & Interfaces

Article Title: Prechondrogenic ATDC5 Cell Attachment and Differentiation on Graphene Foam; Modulation by Surface Functionalization with Fibronectin

doi: 10.1021/acsami.9b14670

Figure Lengend Snippet: Expression of genes encoding extracellular matrix proteins by ATDC5 cells on glass-bottom tissue culture wells, GF, and fibronectin-GF. (A) Time course of gene expression during chondrogenic differentiation for Col1a1 (circle) and Col3a1 (triangle). (B) Relative gene expression levels of Col1a1 (gray) and Col3a1 (black) at day 17 of chondrogenic differentiation in control 2D culture, 2D culture in the presence of fibronectin, 3D-GF, and 3D-GF coated with fibronectin. (C) Time course of gene expression during chondrogenic differentiation for Col2a1 (circle), Col5a1 (triangle), and Col6a1 (square). (D) Relative gene expression levels of Col2a1 (gray), Col5a1 (black), and Col6a1 (white) at day 17 in control 2D culture, 2D culture in the presence of fibronectin, 3D-GF, and 3D-GF coated with fibronectin. (E) Time course of gene expression during chondrogenic differentiation for Ecm1 (circle), Emilin1 (triangle), and Tnc (square). (F) Relative gene expression levels of Ecm1 (gray), Emilin1 (black), and Tnc (white) at day 17 in control 2D culture, 2D culture in the presence of fibronectin, 3D-GF, and 3D-GF coated with fibronectin. (G) Time course of gene expression during chondrogenic differentiation for Fn (circle), Sparc (triangle), and Spp1 (square). (H) Relative gene expression levels of Fn (gray), Sparc (black), and Spp1 (white) at day 17 in control 2D culture, 2D culture in the presence of fibronectin, 3D-GF, and 3D-GF coated with fibronectin. (I) Time course of gene expression during chondrogenic differentiation for Thbs1 (circle), Thbs2 (triangle), and Postn (square). (J) Relative gene expression levels of Thbs1 (black), Thbs2 (white), and Postn (gray) at day 17 in control 2D culture, 2D culture in the presence of fibronectin, 3D-GF, and 3D-GF coated with fibronectin. (K) Time course of gene expression during chondrogenic differentiation for Hapln1 (circle) and Lamb3 (triangle). (L) Relative gene expression levels of Hapln1 (gray) and Lamb3 (black) at day 17 in control 2D culture, 2D culture in the presence of fibronectin, 3D-GF, and 3D-GF coated with fibronectin. Error bars = Mean ± SD Table lists extracellular matrix genes with description, function, and literature citations that corroborate an upregulation during early chondrogenic differentiation.

Article Snippet: Bovine fibronectin protein solution was obtained from R & D Systems (Biotechne Corporation, Minneapolis, MN, U.S.A.) and diluted to a concentration of 100 μg/mL in Ca 2+ - and Mg 2+ -free phosphate-buffered saline (PBS).

Techniques: Expressing, Gene Expression, Control

Journal: ACS Applied Materials & Interfaces

Article Title: Prechondrogenic ATDC5 Cell Attachment and Differentiation on Graphene Foam; Modulation by Surface Functionalization with Fibronectin

doi: 10.1021/acsami.9b14670

Figure Lengend Snippet: Expression of genes encoding matrix remodeling proteins and their endogenous inhibitors by ATDC5 cells on glass-bottom tissue culture wells, GF, and fibronectin-GF. (A) Time course of gene expression during chondrogenic differentiation for Adamts1 (circle) and Adamts2 (triangle). (B) Relative gene expression levels of Adamts1 (gray) and Adamts2 (black) at day 17 of chondrogenic differentiation in control 2D culture, 2D culture in the presence of fibronectin, 3D-GF, and 3D-GF coated with fibronectin. (C) Time course of gene expression during chondrogenic differentiation for Mmp2 (triangle) and Mmp14 (circle). (D) Relative gene expression levels of Mmp2 (black) and Mmp14 (gray) at day 17 in control 2D culture, 2D culture in the presence of fibronectin, 3D-GF, and 3D-GF coated with fibronectin. (E) Time course of gene expression during chondrogenic differentiation for Timp1 (circle), Timp2 (triangle), and Timp3 (square). (F) Relative gene expression levels of Timp1 (gray), Timp2 (black), and Timp3 (white) at day 17 in control 2D culture, 2D culture in the presence of fibronectin, 3D-GF, and 3D-GF coated with fibronectin. (G) Time course of gene expression during chondrogenic differentiation for Ctgf (circle) and Tgfbi (triangle). (H) Relative gene expression levels of Ctgf (gray) and Tgfbi (black) at day 17 in control 2D culture, 2D culture in the presence of fibronectin, 3D-GF, and 3D-GF coated with fibronectin. Error bars = Mean ± SD Table lists matrix remodeling genes analyzed in this study with descriptions and literature citations that have demonstrated a link between increases in gene expression and chondrogenic differentiation.

Article Snippet: Bovine fibronectin protein solution was obtained from R & D Systems (Biotechne Corporation, Minneapolis, MN, U.S.A.) and diluted to a concentration of 100 μg/mL in Ca 2+ - and Mg 2+ -free phosphate-buffered saline (PBS).

Techniques: Expressing, Gene Expression, Control

Journal: ACS Applied Materials & Interfaces

Article Title: Prechondrogenic ATDC5 Cell Attachment and Differentiation on Graphene Foam; Modulation by Surface Functionalization with Fibronectin

doi: 10.1021/acsami.9b14670

Figure Lengend Snippet: ECM Genes Expressed during Chondroprogenitor Cell Differentiation on GF

Article Snippet: Bovine fibronectin protein solution was obtained from R & D Systems (Biotechne Corporation, Minneapolis, MN, U.S.A.) and diluted to a concentration of 100 μg/mL in Ca 2+ - and Mg 2+ -free phosphate-buffered saline (PBS).

Techniques: Cell Differentiation, Binding Assay, Activity Assay, Membrane