HemaBites

HemaBites showcase hematology news and short commentaries on recent high-impact articles published in international journals. This blog will keep you up to date with the latest developments and discoveries in the field of hematology.

Wednesday, July 18, 2018

Catching some rays: UV damage protection in fish hematopoietic stem cells.
Catching some rays: UV damage protection in fish hematopoietic stem cells.
Michael D. Milsom1,2
1. Division of Experimental Hematology, German Cancer Research Center (DKFZ), Heidelberg Germany.
2. Heidelberg Institute for Stem Cell Technology and Experimental Medicine (HI-STEM), Heidelberg, Germany.

 
Kidney_Milsom.pngThe hematopoietic system is particularly sensitive to the action of DNA damaging agents, as evidenced by the fact that myelosuppression is frequently observed in humans upon exposure to ionizing radiation or DNA-damaging chemotherapeutic drugs such as alkylating agents. Indeed, multiple lines of experimental investigation have shown that it is important to protect hematopoietic stem and progenitor cells (HSPCs) from DNA damage in order to avoid both short and long-term adverse effects, such as bone marrow failure and leukemic transformation. In a recently published study, the Zon group have uncovered a mechanism that has evolved in fish in order to protect their HSPCs from the ultraviolet (UV) irradiation co​ntained within sunlight. Unlike in mammals, where the primary location of the adult HSPC niche is within the bone marrow, the adult HSPCs of many fish species reside predominantly within the kidney marrow. Kapp and colleagues made the observation that an umbrella-like structure of melanocytes exists above the kidney marrow in a range of species of fish. They were able to show that this umbrella does indeed protect HSPCs from UVB-induced DNA damage, and is important for sustaining production of mature blood cells. The authors speculate that the need to protect HSPCs from UV damage may explain why the mammalian HSPC niche is located within bones.

Image provided by Leonard Zon and Nymus3D

Animated video explaining the work: https://www.youtube.com/watch?v=e6-CrJOr8zY 

Link and full citation of article:
https://www.nature.com/articles/s41586-018-0213-0
Kapp F.G., et al., Protection from UV light is an evolutionarily conserved feature of the hematopoietic niche. 2018, Nature, 558(7710): pp445-448