Microneedle-Based DNA Tension Gauge Tethers Enable In Vivo Monitoring of Cell Mechanics during Skin Tissue Regeneration.

The mechanical force exerted by dermal fibroblasts is crucial for promoting cutaneous tissue regeneration and wound healing. However, the implantation of a force interface in vivo or within tissue has become a new challenge in measuring mechanical force. Here, we report a microneedle patch with DNA tension gauge tethers (ME-TGT patch) to monitor the mechanical force of dermal fibroblasts in mice. Microneedles served as the force and electrode interface. When the integrin of the fibroblast membrane is successfully recognized by the integrin ligand (cRGDfk) in the tension probe, the duplex splits irreversibly by cellular mechanical force. The conformation rearrangement driven by a mechanical force can be converted into electrochemical signals. The ME-TGT patch can be used for verification of approximately 12 piconewtons (pN) of mechanical force exerted by fibroblasts in vitro and in vivo. Moreover, we used the ME-TGT patch to monitor cell mechanics during wound healing in skin tissue and found fluctuation (rising first and then falling in the process of 0-14 days) in mice. The ME-TGT patch allowed for monitoring mechanical force on fibroblasts in vivo and provided a novel tool for further research into mechanical mechanisms in tissue regeneration.