Page 147 - Physico-Chemical Niche Conditions for Bone Cells

Table 2: Effect of SLBs without and with RGD 17 h of culture.
on MC3T3-E1 pre-osteoblast morphology after
Surface
area (μm2)
3114 ± 279 8929 ± 1421
Eccentricity
0.77 ± 0.02 0.85 ± 0.04 0.89 ± 0.01
0.91 ± 0.01 0.88 ± 0.01 0.87 ± 0.02**
Form factor
0.14 ± 0.02 0.14 ± 0.04 0.11 ± 0.01
0.10 ± 0.01 0.12 ± 0.02 0.12 ± 0.02**
extent
0.36 ± 0.03 0.31 ± 0.07 0.28 ± 0.03
0.21 ± 0.03 0.31 ± 0.04 0.30 ± 0.04**
Volume (μm3)
Chapter 6
PLL
SLB
+0.2 μM RGD
+0.5 μM RGD
+1.0 μM RGD
SLB ± RGD
1652 ± 283 1821 ± 235
2146 ± 194# 1666 ± 233 1763 ± 227*
6652 ± 1281 6118 ± 664
5963 ± 1019 5963 ± 382 6174 ± 737**
Notes: The morphological parameter values for surface area, volume, eccentricity, form factor, and extent are mean ± SEM. SLB ± RGD values are mean ± SEM of pooled data of all SLB experimental groups. Cells on SLBs without or with RGD had a smaller surface area, smaller volume, larger eccentricity, smaller form factor, and lower extent than cells on PLL. Cells on SLBs with 0.5 μM RGD exhibited a larger surface area than cells on SLBs without RGD or with 1.0 μM RGD. n > 300 cells. Significantly different from PLL, *p < 0.05, **p < 0.001. #Significant effect of RGD, p < 0.05. Abbreviations: PLL, poly-L-lysine; SLB, supported lipid bilayer.
To quantify the shape of the cell surface, elongation, circularity, and extent were quantified. Cells on SLBs with and without RGD were more elongated, less circular, and showed more protrusions than cells on PLL-coated glass (Table 2; p < 0.001). On PLL-coated glass a higher percentage of cells was less elongated (eccentricity <0.8), and a lower percentage of cells exhibited higher elongation (eccentricity >0.9) than on SLBs with or without RGD (Figure 4d; p < 0.05). The percentage of cells with an extent between 0.25 and 0.50 was increased, and the percentage of cells with an extent between 0 and 0.25 decreased on PLL- coated glass compared to SLBs with or without RGD (Figure 4(e); p < 0.05).
On all substrates more than 75% of the cells had a form factor less than 0.2, and no cell had a form factor higher than 0.7, confirming that the cells were generally elongated (Figure 4f). No significant differences were observed between cells on SLBs with and without RGD, although the averages for eccentricity, form factor, and extent seemed to indicate that cells on SLBs with 0.5 μM RGD were somewhat more elongated, less circular, and exhibited more protrusions than cells on SLBs without RGD (Table 2).
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