Previous work demonstrated an accelerated in vitro and in vivo wound healing response when insulinoma cells were used to deliver insulin to scratches in keratinocyte mono- layers and chronic diabetic excise wounds in mice, respectively. When combined with mesenchymal stem cells (MSCs), the response was amplified (healing in 14 vs. 35+ days). To isolate the role of insulin in the response and exclude any potential contribution of an un known cancer moiety released by the insulinoma cells, the effect on wound healing of multiple lines derived from the same insulinoma was examined.
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Validating Hydrogel Microencapsulated Insulin Secreting Cells for Wound Healing
Previous work demonstrated an accelerated in vitro and in vivo wound healing response when insulinoma cells were used to deliver insulin to scratches in keratinocyte mono- layers and chronic diabetic excise wounds in mice, respectively. When combined with mesenchymal stem cells (MSCs), the response was amplified (healing in 14 vs. 35+ days). To isolate the role of insulin in the response and exclude any potential contribution of an unknown cancer moiety released by the insulinoma cells, the effect on wound healing of multiple lines derived from the same insulinoma was examined.
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- Award ID(s):
- 1752079
- NSF-PAR ID:
- 10138989
- Date Published:
- Journal Name:
- Northeast Bioengineering Conference
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Background Wound healing is one of the defining features of life and is seen not only in tissues but also within individual cells. Understanding wound response at the single-cell level is critical for determining fundamental cellular functions needed for cell repair and survival. This understanding could also enable the engineering of single-cell wound repair strategies in emerging synthetic cell research. One approach is to examine and adapt self-repair mechanisms from a living system that already demonstrates robust capacity to heal from large wounds. Towards this end, Stentor coeruleus , a single-celled free-living ciliate protozoan, is a unique model because of its robust wound healing capacity. This capacity allows one to perturb the wounding conditions and measure their effect on the repair process without immediately causing cell death, thereby providing a robust platform for probing the self-repair mechanism. Results Here we used a microfluidic guillotine and a fluorescence-based assay to probe the timescales of wound repair and of mechanical modes of wound response in Stentor . We found that Stentor requires ~ 100–1000 s to close bisection wounds, depending on the severity of the wound. This corresponds to a healing rate of ~ 8–80 μm 2 /s, faster than most other single cells reported in the literature. Further, we characterized three distinct mechanical modes of wound response in Stentor : contraction, cytoplasm retrieval, and twisting/pulling. Using chemical perturbations, active cilia were found to be important for only the twisting/pulling mode. Contraction of myonemes, a major contractile fiber in Stentor , was surprisingly not important for the contraction mode and was of low importance for the others. Conclusions While events local to the wound site have been the focus of many single-cell wound repair studies, our results suggest that large-scale mechanical behaviors may be of greater importance to single-cell wound repair than previously thought. The work here advances our understanding of the wound response in Stentor and will lay the foundation for further investigations into the underlying components and molecular mechanisms involved.more » « less
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