Zebrafish share skin-deep similarities with people, making them helpful models to study skin conditions like vitiligo and melanoma
They do this by synthesizing melanins, which are pigments sent to other skin cells to shield them from harmful ultraviolet light.
- They do this by synthesizing melanins, which are pigments sent to other skin cells to shield them from harmful ultraviolet light.
- A lack of functioning melanocytes causes a wide range of skin conditions, including skin cancer and vitiligo, an autoimmune condition in which the body attacks melanocytes and causes patches of depigmented skin.
- Difficulties growing human melanocytes in cell cultures have led researchers like me to use alternative models to study them.
What zebrafish and people have in common
- Melanocytes in zebrafish are similar in many ways to those in people.
- Unlike melanocytes in mouse or human skin, zebrafish melanocytes are externally visible in their dark stripes and spotted scales.
- Importantly, researchers can manipulate and perform experiments on zebrafish melanocytes in ways that are unethical or not feasible to do with people.
Diversity of melanocyte stem cells
- It’s also relevant to age-related conditions like hair graying, in which melanocyte stem cells either die or become dormant and no longer produce the mature melanocytes that give hair its color.
- Since melanocyte stem cells in zebrafish are externally visible, we tracked these cells in real time to see how they divided and matured.
- Additionally, we measured which genes were expressed in individual melanocyte stem cells and their descendants during regeneration.
- We found that dying melanocytes trigger this regenerative process by sending the signal for melanocyte stem cells – cells that can give rise to new melanocytes – to activate.
From fish to people
- When we examined cells taken from the fluid within a blister in human skin, we found cells that look remarkably similar to zebrafish melanocyte stem cells.
- We are planning to see whether these human cells are activated in skin regeneration to make new melanocytes, which would confirm their identity as melanocyte stem cells.