ENGINEERING ARTIFICIAL STEM CELL NICHES - Biologically-Responsive Hybrid Biomaterials - page 292

c

b

a d

Fig. 7. Therapeutic manipulation of the natural niche using biomaterials-based approaches. Local
delivery of bioactive niche components or inhibitory/stimulatory molecules from a solid
(injectable) biomaterial scaffold (a). Targeting the niche via micro- or nanoparticles that carry and
delivery bioactive molecules to manipulate the niche (b). Local delivery of support cells to
augment or manipulate stem cell fates in vivo (c). Cell delivery could be facilitated using
(injectable) biomaterials carriers that likely improve the survival and engraftment of the
transplanted cells. Implanted, multicomponent artificial niche that could possibly attract stem cells
to populate it (d). Reproduced with permission Reproduced with permission from 100 . Copyright
2009 Wiley InterScience.

colleagues and others. 96,97,98 Secondly, biomaterials concepts could be harnessed
to locally deliver cellular components of stem cell niches (Fig. 7c) . 'Smart' cell
delivery systems which have been shown to improve the survival, engraftment,
and fate of transplanted cells are now available, as has been reviewed
elsewhere. 99 Finally and maybe most excitingly, it is conceivable that
multicomponent, potentially injectable materials could be designed to act as
de novo niches in vivo (Fig. 7d) . If appropriate 'homing' signals were present to
attract endogenous stem cells to these artificial niches and localize the stem cells
via known cell-cell or cell-matrix adhesive interactions, and signals were present,
which could control stem cell function, such efforts have an important impact in
the near future.

References

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and adult fibroblast cultures by defined factors. Cell 126 , 663-676 (2006).
2 Daley, G. Q. & Scadden, D. T. Prospects for stem cell-based therapy. Cell 132 , 544-548,
doi:Doi 10.1016/J.Cell.2008.02.009 (2008).
3 Watt, F. M. & Hogan, B. L. Out of Eden: stem cells and their niches. Science 287 , 1427-1430
(2000).