Peptide-decorated surfaces

Peptide-Decorated Surfaces for Spatially Guided Cell Adhesion. 56... 

Figure 21.11. Schematic demonstrating the proposed function of peptide decorated microcapsules for cell driven, ordered self-assembly of capsules and promotion of cell activities intended for tissue repair and regeneration. Red spheres represent capsules decorated with extracellular matrix (ECM) integrins and/or carbohydrate moieties attached to the chitosan shell. Biolinkages can spontaneously form between capsules and with cells bearing complementary surface markers in a co-rdinated manner. Yellow sppheres represent human progenitors. The purpose is to promote optimal cell-cell and cellmatrix linkages.

Capsules of this kind were immersed in a primary hBMSC cell suspension to test the potential of peptide decorated capsules to attach cells to the external surface. It was found that within 7 days metabolically active/viable primary hBMSC preferentially adhered to chitosan-GGRGD complexed capsules (Figure 14B,D). In capsules without chitosan conjugated GGRGD ligands only a few cells were seen to be attached (Figure 14A,C). 

Another report showed that cyclodextrin vesicles (CDVs) (Section 5.3) can be decorated with peptides functionalized with an adamantane anchor. It was found that a (LeuGlu)4 octapeptide can induce a pH-dependent shape transformation of the vesicles at pH 7.4, the peptide merely binds to the vesicle surface, whereas at pH 5.0 it forms a jS-sheet and transforms the vesicles into a nanotube (Figure 7). It was shown that the vesicles release their contents as a result of this shape transformation. It should be emphasized that the pH range of this shape transformation matches the decrease in pH that occurs upon endosomal uptake by cells. Hence, these experiments suggest that the peptide-decorated CDVs may be a useful vehicle for intracellular delivery of drugs or antigens that are encapsulated inside the vesicle or bound on the surface of the vesicle. 

The potential of SPAAC in peptide-polymer conjugation was successfully demonstrated by Chaikof and coworkers using a cyclooctyne-functionalized peptide for surface decoration (Figure 1.14). It vwis shown that a... 

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