Figure 7.

Cell attachment and spreading were quantified for substrates presenting FN9−10, FN10, and FN9m−10 at densities ranging from 0.00001 to 0.1%. (A) Cells adhered to substrates presenting FN9−10 at densities down to 0.0001% protein, while no attachment to FN10 and FN9m−10 was observed below a density of 0.001%. The average number of cells that attached to substrates presenting FN9−10 substrates at densities of 0.001% and 0.0001% were statistically greater than the averages for FN10 and FN9m−10 at the same densities (asterisk indicates p < 0.0005). (B) Cell spreading significantly increased for all three proteins above a density of 0.01% protein. Cells on FN10 remained slightly less spread than FN9−10 and FN9m−10 for surfaces presenting protein at densities of 0.05% and 0.01% (asterisk indicates p < 0.0005; pound symbol indicates p < 0.025). Averages were determined from three experiments, where seven images were captured per chip.