A nurse cares for a premature baby (M. Spencer Green / AP)

A woman's immune system balances two jobs during pregnancy: preventing itself from attacking the fetus as it would foreign tissue and keeping the mother safe from infection herself. Disruptions to this balance can cause a host of complications for the pregnancy, namely delivery at 34 weeks — six weeks sooner than what is considered normal and healthy. In the U.S., 10–12% of babies are born before full term.

Stanford researchers have detailed what this balance (referred to as the "immune clock") should look like in a pregnancy in which the baby is delivered at term, per a new study.

Why it matters: "Once you understand what is normal…you can understand what is abnormal," Brice Gaudilliere, one of the researchers, told Axios. With the model "immune clock" on hand, doctors may be able to predict whether a woman will deliver preterm by observing if that clock is ticking too slow or too fast.

How it works: The researchers looked at blood samples from patients at three points during their pregnancies and six weeks after giving birth. They counted the types of immune cells present and analyzed how the individual cells and networks of signaling pathways reacted to bacteria.

They found pregnant women's immune systems change on a strict, universal schedule:

  • The adaptive immune system, which consists of antibodies and white blood cells that learn to fight pathogens, recedes.
  • The innate immune system, which is the body's set of ingrained defense mechanisms, such as inflammation at the site of an infection, picks up the slack.

What's next: One goal is to predict the timing of labor with the "immune clock," which Gaudilliere says is already underway in their lab. They're also trying to figure out what makes immune cells deviate from normal in women who deliver preterm. Nima Aghaeepour, another researcher on the study, told Axios they hope this insight will be able to teach those cells how to fix themselves — similar to the CAR-T cancer therapy approved by the FDA earlier this week.

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Trump tightens screws on ByteDance to sell Tiktok

Illustration: Aïda Amer/Axios

President Trump added more pressure Friday night on China-based TikTok parent ByteDance to exit the U.S., ordering it to divest all assets related to the U.S. operation of TikTok within 90 days.

Between the lines: The order means ByteDance must be wholly disentangled from TikTok in the U.S. by November. Trump had previously ordered TikTok banned if ByteDance hadn't struck a deal within 45 days. The new order likely means ByteDance has just another 45 days after that to fully close the deal, one White House source told Axios.

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Coronavirus dashboard

Illustration: Aïda Amer/Axios

  1. Global: Total confirmed cases as of 9:30 p.m. ET: 21,056,850 — Total deaths: 762,293— Total recoveries: 13,100,902Map.
  2. U.S.: Total confirmed cases as of 9:30 p.m ET: 5,306,215 — Total deaths: 168,334 — Total recoveries: 1,796,309 — Total tests: 65,676,624Map.
  3. Health: CDC: Survivors of COVID-19 have up to three months of immunity Fauci believes normalcy will return by "the end of 2021" with vaccine — The pandemic's toll on mental health — FDA releases first-ever list of medical supplies in shortage.
  4. States: California passes 600,000 confirmed coronavirus cases.
  5. Cities: Coronavirus pandemic dims NYC's annual 9/11 Tribute in Light.
  6. Business: How small businesses got stiffed — Unemployment starts moving in the right direction.
  7. Politics: Biden signals fall strategy with new ads.

Harris: "Women are going to be a priority" in Biden administration

Sen. Kamala Harris at an event in Wilmington, Del. Photo: Drew Angerer/Getty Images

In her first sit-down interview since being named Joe Biden's running mate, Sen. Kamala Harris talked about what she'll do to fight for women if elected VP, and how the Democrats are thinking about voter turnout strategies ahead of November.

What they're saying: "In a Biden-Harris administration women are going to be a priority, understanding that women have many priorities and all of them must be acknowledged," Harris told The 19th*'s Errin Haines-Whack.