to a neuregulin fibronectin is a high molecular weight u02dc 440 kda glycoprotein of the extracellular matrix that binds to membrane spanning receptor proteins called integrins similar to integrins fibronectin binds extracellular matrix components such as collagen fibrin and heparan sulfate proteoglycans e g syndecans likewise ngf p75 notch 1 and slug too plays an important role in neuroectoderm colony forming unit cfu assay was determined by the plating of 100 cells in 35 mm dishes bd falcon after 14 days in culture the cells were removed and washed twice using dpbs u2014 ca2 u2014 mg2 and fixed in 100 methanol sigma aldrich malaysia for 15 to 20 minutes at room temperature 23 u00b1 1 u00b0 c the cells were then stained with 0 5 crystal violet sigma aldrich for 30 minutes at room temperature 23 u00b1 1 u00b0 c followed by four times rinsing with tap water to remove the violet stain the dish was inverted on absorbent paper and allowed to dry only colonies of more than 2 mm in diameter were counted the cfu was calculated using the following formula the colony forming properties of scds dpscs and pdlscs were assessed at passage 3 finish product refer fig5 as indicated in figure below all cell lines were able to form colonies indicating their msc characterization the mean percentage of colony forming unit cfu were higher in dpscs 73 5 u00b1 4 95 as compared with those of scds 65 0 u00b1 7 07.