New imaging method puts blood stem cells in high-resolution spotlight

With a microscope and a little help in zebrafish, for the first time, researchers can obtain high-resolution views of individual blood stem cells

"Currently, we study stem cells in tissues with a limited number of labels and at low resolution, but we're missing a lot of information," said Owen Tamplin, assistant professor in the UW-Madison Department of Cell and Regenerative Biology, Stem Cell and member of the Center for Regenerative Medicine and co-author of the new study, published Aug.

A niche is a microenvironment found in tissues such as the bone marrow, which contains hematopoietic stem cells that support the blood system

"This allows us to identify cell types in the microenvironment that we didn't even know interact with stem cells, which opens up new research directions," Tamplin said

As part of the study, Tamplin and his colleagues, including co-first authors Sobhika Agarwala and Keunyoung Kim, identified dopamine beta-hydroxylase-positive ganglion cells, cells previously uncharacterized in the blood stem cell niche type

Zebrafish larvae make it easier to visualize blood stem cell development, but specialized imaging is required to spot such small cells and then to characterize their ultrastructure in detail

Tamplin hopes this approach can be used for many other types of stem cells, such as those in the gut, lung and tumor microenvironments, where rare cells need to be characterized at nanometer resolution

"I think it's very exciting because all of our blood stem cells are created during embryonic development, and depending on what organism you are, hundreds or thousands of stem cells end up in your Hundreds of billions of new blood cells are produced every day over a lifetime