Hydrogels for Stem Cell Fate Control and Delivery in Regenerative Medicine - In-Situ Gelling Polymers: For Biomedical Applications - page 200

cell fate and function. Such components may be support cells and/or biomolecules
and drugs that might affect stem cell fates (survival, self-renewal and differen-
tiation). Notably, with the advances in hydrogel chemistries and micropatterning
techniques, we can now control the spatial organization of cells and biomolecules
and study the cell-cell and cell-matrix interactions over space and time in a well-
controlled manner. Looking forward, defining the specific niche components
present in the stem cell microenvironment and deciphering the underlying mech-
anisms will allow researchers to develop new therapeutics to enhance stem cell
function and promote regeneration of injured or diseased tissues in vivo.
As mentioned, the tissue environment is dynamic in nature and present spa-
tial and temporal heterogeneity in the cellular and matrix composition, and this
dynamics is highly impacted by the type and state of the tissue environment,
whether in healthy or injured/diseased state. Oxidative stress and inflammation
present in the injured/diseased tissue environment are likely to affect the mobiliza-
tion of stem cells from the stem cell niche as well as the survival and engraftment
of exogenous stem cells, and are therefore important considerations when deliver-
ing cells in injectable hydrogels to the site of tissue injury. Looking forward, strat-
egies of anti-inflammation and/or anti-oxidative injury may be incorporated into
multifunctional hydrogels to modify the tissue environment and help in the sur-
vival/engraftment of the transplanted cells. Modulating the cellular processes and
guiding the development of the neotissue formation in parallel with the changes of
the tissue environment would be pivotal in determining the outcome of the regen-
erative therapy.
Looking into the future, combined approaches utilizing hydrogels, microtech-
nologies and controlled release strategies will provide new insights into the mech-
anistic regulation of stem cell fate. These advances in hydrogel design and related
enabling technologies will continue to grow and aid in our future design of cus-
tomized hydrogel delivery systems for healthy and injured/diseased tissues, and
guide the development of future therapies.
Acknowledgement This work was supported by National University of Singapore, National
University Healthcare System, Ministry of Education and A*STAR SERC Personal Care IAF.
Disclosure The author indicates no potential conflict of interest.
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