Introduction 9 27 34 X 10 11 13 35 41 43 27 2 1 4 1 1 10 11 27 2 43 12 42 3 28 37 40 17 11 2 32 33 in vivo 20 21 22 36 5 6 26 29 30 39 44 15 16 24 25 29 31 38 X Materials And Methods All chemicals were purchased from Sigma–Aldrich (St. Louis, MO) unless otherwise stated. Synthesis of Polyethylene Glycol Diacrylate 2 3 4 N N 7 Synthesis of PEG Derivatives Containing Cell Adhesion Molecules N′ 5 6 N X X −1 X X Synthesis of Bilayered PEG Copolymer Hydrogels −1 N −1 −1 −2 −1 X −1 N −2 Cell Maintenance l −1 −1 2 Cell Adhesion and Rolling on Adhesive PEG Gels 1 −2 in vivo Figure 1. Schematic of parallel plate flow chamber system. A small pump is used to create a vacuum, sealing the chamber on the surface of the gel. Cells are then perfused over the gel surface using a programmable syringe pump.  Cation Dependent Binding 2+ 2+ 2+ 2+ 2+ −2 LDV Specificity 2+ −1 1 1 −2 −2 Video Analysis Cells were allowed to settle on each gel for 5 min. An average of 10 fields of view was scanned and the number of cells settled on the peptide gel was counted. After flow began, fields of view were scanned again and the number of cells remaining (bound to the gel) was counted. After flow was established on the SLeX gels, video was paused and the number of interacting cells was counted. The numbers were averaged over 10 fields of view for each shear stress. Statistical Analysis t p Results Synthesis of PEG Hydrogels 1 Quantification of Cell Adhesion and Rolling −2 −1 2 −2 −1 −2 −1 −2 Figure 2. p −2  4 1 3 Figure 3. −2 p  Cation Dependant Binding 2+ 2+ 2+ 4 Figure 4. 2+ 2+ −2 p  LDV Specificity 5 Figure 5. −2  6 Figure 6. p  Discussion 4 7 15 16 18 24 – 26 29  – 31 38 39 44 23 8 14 45 36 X X in vivo Conclusions in vivo