UAB Study Links Immunosuppressant Induced NFAT Disruption to Preeclampsia in Transplant Pregnancies

UAB Researchers Link Transplant Immunosuppression To Pre-Eclampsia Through New NFAT Pathway Discovery

USA: A team at the University of Alabama at Birmingham has identified a surprising immune pathway that may explain why pregnancies after transplantation are at higher risk for pre-eclampsia. The investigation, sparked by lessons learned following UAB’s first uterine transplant four years ago, centers on the molecule NFAT and how commonly used immunosuppressive medications alter its behavior in ways that can undermine placental development. The National Institutes of Health notes pre-eclampsia affects around 8 percent of pregnancies in the U.S. and contributes to more than 50,000 maternal deaths worldwide each year, underscoring the clinical stakes.

Researchers report that NFAT, long known for “arming” T cells that fight infection and which immunosuppressants are designed to mute, has an additional, vital role in pregnancy. The molecule issues a retention signal for natural killer (NK) cells in the uterine environment; those NK cells are essential architects of the developing placenta. When NFAT signaling is blunted by transplant-focused drugs, NK cells fail to remain in place and cannot perform their developmental duties.

The team theorizes that this unintended consequence of standard anti-rejection therapy helps explain the elevated incidence of pre-eclampsia observed in solid organ transplant recipients versus the general population. By tracing the chain from drug to molecular switch to cellular displacement to impaired placental formation, investigators have opened a mechanistic window on a perplexing clinical pattern that has long vexed transplant and maternal-fetal specialists.

Leaders of the study frame the discovery as a first but pivotal step toward safer pregnancies for transplant recipients. Their goal is to translate the NFAT pathway insight into revised immunosuppression strategies or novel medications that preserve the anti-rejection benefits while protecting the NK cell signals necessary for healthy placental development, potentially preventing serious pregnancy complications in this vulnerable population.

Video originally published on 2026-03-11 18:35:07