Wounding Zebrafish Larval Epidermis by Laceration.

Wound healing is a critical process for maintaining the integrity of tissues, driven in large part by the active migration of cells to cover damaged regions. While the long-term tissue injury response over hours and days has been extensively studied, the rapid early migratory response of cells to injury in vivo is still being uncovered, especially in model systems such as zebrafish larvae, which are ideal for live imaging with high spatiotemporal resolution. Observing these dynamics requires a wounding method that prompts a robust wound response and is compatible with immediate live imaging or other downstream applications. We have developed a procedure for wounding the epidermis in the tailfin of larval zebrafish, which we term "tissue laceration". In this procedure, the tailfin is impaled with a glass needle that is then dragged through the tissue, which generates a full-thickness wound that elicits a dramatic migratory wound response within seconds from cells up to several hundred micrometers away from the wound. Laceration generates a larger wound response in the first few minutes following wounding compared to other mechanical wounds such as tail transection, and laceration does not require specialized equipment compared to laser wounding methods. This procedure can be used to interrogate the processes by which epidermal cells far away from the wound are able to rapidly detect injury and respond to the wound.