Sign up for our daily briefing

Make your busy days simpler with Axios AM/PM. Catch up on what's new and why it matters in just 5 minutes.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Catch up on the day's biggest business stories

Subscribe to Axios Closer for insights into the day’s business news and trends and why they matter

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Stay on top of the latest market trends

Subscribe to Axios Markets for the latest market trends and economic insights. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Sports news worthy of your time

Binge on the stats and stories that drive the sports world with Axios Sports. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Tech news worthy of your time

Get our smart take on technology from the Valley and D.C. with Axios Login. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Get the inside stories

Get an insider's guide to the new White House with Axios Sneak Peek. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Denver news?

Get a daily digest of the most important stories affecting your hometown with Axios Denver

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Des Moines news?

Get a daily digest of the most important stories affecting your hometown with Axios Des Moines

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Twin Cities news?

Get a daily digest of the most important stories affecting your hometown with Axios Twin Cities

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Tampa Bay news?

Get a daily digest of the most important stories affecting your hometown with Axios Tampa Bay

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Charlotte news?

Get a daily digest of the most important stories affecting your hometown with Axios Charlotte

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Nashville news?

Get a daily digest of the most important stories affecting your hometown with the Axios Nashville newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Columbus news?

Get a daily digest of the most important stories affecting your hometown with the Axios Columbus newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Dallas news?

Get a daily digest of the most important stories affecting your hometown with the Axios Dallas newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Sign up for Axios NW Arkansas

Stay up-to-date on the most important and interesting stories affecting NW Arkansas, authored by local reporters

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Nati Harnik / AP

A new study published Wednesday may help scientists develop preventative measures against gestational diabetes, recurrent spontaneous miscarriage, and other pregnancy complications.

What they found: The human immune system matures in utero as early as the second trimester but has a tweak — a greater amount of protein arginase-2 — which may allow for greater immune tolerance, according to the scientists behind the semi-controversial study.

Why the findings matter: The knowledge could help guide the timing of intra-uterine stem cell transplants or other gene therapies that could save the life of a fetus or help prevent immune-related issues like gestational diabetes and miscarriages, per an article in Nature. The knowledge could also be applied to helping remedy some adult afflictions, like avoiding the rejection of organ transplants.

Study author Florent Ginhoux told Axios the study was the first to have "clearly mapped the system of this network of cells in human tissue." He said little is known about the initial stages of development for cells central to the immune system in the womb due to ethical concerns surrounding the use of fetal tissue in experiments.

Study details: Ginhoux teamed up with Singapore clinician Jerry Chan, who conducts experimental gene and cell therapies to treat fetal diseases. They studied tissues from 96 fetuses (from clinically indicated pregnancy terminations) from the second trimester of pregnancy and sorted out the immune cells, which they found in the skin, spleen, thymus, and lungs. They exposed the cells to toxic antigens and to non-related adult cells to see if they would trigger an immune response.

Similar to adult cells: They found there were immunologically active cells, called dendritic cells, which showed the capacity to both sense pathogens and stimulate T cells in the second trimester of gestation. The fetal dendritic cells responded to regular antigens in a similar manner as adult dendritic cells react.

Different from adult cells: However, when exposed to adult cells as the antigen, the fetal dendritic cells did not respond with an immune response as adult cells would (think of the immune problems with kidney transplants) but dampened the immune response. The team said the cause of this may be greater amounts of the protein arginase-2, which is found in abundance in fetal dendritic cells but not adult ones.

Immune tolerance and going forward: Arginase-2 is the likely explanation of "immune tolerance" between mother and fetus, where neither immune system attacks the other, Ginhoux said. He said this is important because further studies could see if this tolerance can be applied to adults. While this study discovered one pathway of immunosuppression, Ginhoux said more research is needed to discover other pathways of immunosuppression and to completely map whole system of cell development in fetuses.

Go deeper

Biden rejects Trump's latest executive privilege claims

Photo: Jim Watson and Saul Loeb/AFP via Getty Images

The White House on Monday rejected two more of former President Trump's claims of executive privilege over documents that the House select committee investigating the Jan. 6 Capitol riot requested, CNN first reported.

Why it matters: Trump's legal team is seeking to block some of the panel's requests for records by invoking executive privilege, which can allow presidents and their aides to sidestep congressional scrutiny. The Biden administration has maintained that it will evaluate on a case-by-case basis.

Amazon warehouse workers in New York file petition to hold unionization vote

Amazon workers and their supporters rally outside the National Labor Relations Board's regional office in Brooklyn, New York City, after filing a petition requesting an election to form a union. Photo: Gabby Jones/Bloomberg via Getty Images

Amazon warehouse workers in New York City filed a petition on Monday with the National Labor Relations Board (NLRB) to hold a vote on unionization.

Why it matters: The move comes six months after an organizing effort was defeated at Amazon's distribution center in Alabama.

Updated 3 hours ago - World

U.S. freezes aid to Sudan over military coup

Protesting the coup in Khartoum. Photo: AFP via Getty

The Biden administration froze a $700 million aid package to Sudan after a military coup on Monday threatened to end the country's transition toward democracy.

Driving the news: At least three protesters have been killed and dozens wounded in the chaotic scenes that followed the announcements from Gen. Abdel Fattah al-Burhan, the head of Sudan's ruling council, dissolving the government and declaring a state of emergency.