Scientists Grow Blood Stem Cells in the Lab for the First Time

iStock
iStock

One little cell can go a very long way—especially if that cell is a blood stem cell. Now two research groups have developed two different methods for growing these cells, a development that could help us understand and fight cancer. The scientists published their papers in the journal Nature.

Hematopoietic, or blood-making, stem cells (HSCs) are extraordinary things, so full of creative potential that a single cell can be used to restore an entire mammal circulatory system. Unfortunately, this same generative power also makes them prone to developing cancer-causing genetic mutations. If we could figure out how these HSCs work, we might be able to separate their skills from their weaknesses.

The most efficient way to access and study these complex cells would be to grow them in the lab. The authors of the new papers present two different approaches that may get us there.


Hematopoietic stem and progenitor cells (HSPC) from human iPS cells.
Rio Sugimura

The first group, led by Boston-based cancer experts George Daley and Ryohichi Sugimura, used chemical signals and genetic tinkering to transform human pluripotent stem cells into blood cells, and then, from there, into human HSCs.

The second team, led by Weill Cornell Medicine's Shahin Rafii and Raphael Lis, started with blood cells taken from mice, then changed the cells’ genes to coax them into becoming mouse HSCs.


Guibentif & Göttgens 2017. Nature.

Both groups’ freshly minted HSCs were functional, surviving transplant and producing more blood cells once they’d settled in.

Writing in an accompanying News & Views article for Nature, researchers Carolina Guibentif and Berthold Göttgens say both teams’ progress “opens up exciting opportunities” in the field. They note that neither method solves the problem of cancer-causing mutations, and the new cells’ success was only tracked for a short period of time.

Still, “although further studies are needed,” they write, “the long journey to translate the promise of stem-cell research into direct patient benefit may just have become a little shorter.”

This Gorgeous Vintage Edition of Clue Sets the Perfect Mood for a Murder Mystery

WS Game Company
WS Game Company

Everyone should have a few good board games lying around the house for official game nights with family and friends and to kill some time on the occasional rainy day. But if your collection leaves a lot to be desired, you can class-up your selection with this great deal on the Vintage Bookshelf Edition of Clue for $40.

A brief history of Clue

'Clue' Vintage Bookshelf Edition.
WS Game Company.

Originally titled Murder!, Clue was created by a musician named Anthony Pratt in Birmingham, England, in 1943, and he filed a patent for it in 1944. He sold the game to Waddington's in the UK a few years later, and they changed the name to Cluedo in 1949 (that name was a mix between the words clue and Ludo, which was a 19th-century game.) That same year, the game was licensed to Parker Brothers in the United States, where it was published as Clue. Since then, there have been numerous special editions and spinoffs of the original game, not to mention books and a television series based on it. Most notably, though, was the cult classic 1985 film Clue, which featured Eileen Brennan, Tim Curry, Madeline Kahn, Christopher Lloyd, Michael McKean, Martin Mull, and Lesley Ann Warren.

As you probably know, every game of Clue begins with the revelation of a murder. The object of the game is to be the first person to deduce who did it, with what weapon, and where. To achieve that end, each player assumes the role of one of the suspects and moves strategically around the board collecting clues.

With its emphasis on logic and critical thinking—in addition to some old-fashioned luck—Clue is a masterpiece that has stood the test of time and evolved with each decade, with special versions of the game hitting shelves recently based on The Office, Rick and Morty, and Star Wars.

Clue Vintage Bookshelf Edition

'Clue' Vintage Library Edition.
WS Game Company

The Vintage Bookshelf Edition of Clue is the work of the WS Game Company, a licensee of Hasbro, and all the design elements are inspired by the aesthetic of the 1949 original. The game features a vintage-looking game board, cards, wood movers, die-cast weapons, six pencils, an ivory-colored die, an envelope, and a pad of “detective notes.” And, of course, everything folds up and stores inside a beautiful cloth-bound book box that you can store right on the shelf in your living room.

Clue Vintage Bookshelf Edition is a limited-release item, and right now you can get it for $40.

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Tear Gas vs. Pepper Spray: What’s the Difference?

This is probably pepper spray.
This is probably pepper spray.
Siberian Photographer/iStock via Getty Images

Pepper spray and tear gas are both non-lethal irritants that cause extreme burning of the eyes, nose, and throat—but there are a few key differences between the two substances.

For one, they’re created from different chemicals. According to biohazard remediation company Aftermath, the active ingredient in pepper spray is oleoresin capsicum, which comes from the compound that makes hot peppers so hot: capsaicin. If you’ve ever accidentally rubbed your eyes after chopping a chili pepper, you’ve gotten a very tiny taste of what it’s like to be sprayed with pepper spray. Tear gas, on the other hand, contains 0-Chlorobenzylidenemalononitrile (CS), 2-chlorobenzalmalononitrile (CN), or a similar artificial chemical. At room temperature, both of those chemicals are powdery solids, not gases—they’re mixed with liquids or gases so they can be dispersed in the air.

Delivery methods differ, too. Pepper spray often comes in an aerosol can, which shoots it in a stream, a mist, or some other relatively direct path (though it’s also available as a gel or foam). As the Berkeley Science Review explains, tear gas is mainly dispersed with a grenade, which releases the substance over a wide area when it explodes. Since the grenades can cover so much ground, law enforcement officers are more likely to use tear gas to try to break up a crowd, and civilians are more likely to carry pepper spray as a personal safety measure.

The immediate effects of the two substances are similar—burning sensation in mucous membranes, rise in blood pressure, difficulty breathing, runny nose, etc.—but tear gas can also cause nausea and vomiting in higher concentrations.

For more on tear gas, including what to do if you’re exposed to it, head here.

[h/t Aftermath]