Sep 5, 2017

How the immune system acts during pregnancy

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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World coronavirus updates: Confirmed cases top 1 million

Data: The Center for Systems Science and Engineering at Johns Hopkins, the CDC and China's Health Ministry. Note: China numbers are for the mainland only and U.S. numbers include repatriated citizens and confirmed plus presumptive cases from the CDC

Novel coronavirus infections have hit the 1 million mark after "near exponential growth" that's reached "almost every country," World Health Organization Director-General Tedros Adhanom Ghebreyesus said Thursday.

The big picture: The global death toll exceeded 50,000 on Thursday, per Johns Hopkins data. Italy has reported nearly 14,000 deaths. Governments around the world have introduced public health and economic measures to try and curb the impact of the virus.

Go deeperArrowUpdated 25 mins ago - Health

Coronavirus dashboard

Illustration: Sarah Grillo/Axios

  1. Global: Total confirmed cases as of 6 p.m. ET: 1,007,997 — Total deaths: 52,771 — Total recoveries: 210,055Map.
  2. U.S.: Total confirmed cases as of 6 p.m. ET: 236,339 — Total deaths: 5,648 — Total recoveries: 8,861Map.
  3. 2020 update: The Democratic National Committee said its July convention will be postponed until August because of the coronavirus.
  4. Jobs latest: The coronavirus unemployment numbers are like a natural disaster hitting every state
  5. Public health latest: FDA allows blood donations from gay men after 3-month waiting period, citing "urgent need."
  6. U.S.S. Theodore Roosevelt: Navy removes captain of aircraft carrier who sounded alarm about coronavirus.
  7. What should I do? Answers about the virus from Axios expertsWhat to know about social distancingQ&A: Minimizing your coronavirus risk.
  8. Other resources: CDC on how to avoid the virus, what to do if you get it.

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Judge declines to delay Wisconsin April 7 primary, extends absentee deadline

Photo: Darren Hauck/Getty Images

A federal judge on Thursday declined to delay Wisconsin's April 7 primary election, saying he doesn't have the authority to do so.

Why it matters: Wisconsin is the only state scheduled to vote next Tuesday that has not yet delayed its primary.