Nicotine exposure during pregnancy and shortly after birth caused lasting changes to the blood-forming stem cells and the developing immune system in mice, including a more damaging response to influenza infection later in life, researchers found.
The research team, led by Camilla Forsberg at the University of California, Santa Cruz, USA, exposed pregnant mice to nicotine to investigate the effects of perinatal nicotine exposure (PNE) to the blood building system. The researchers found that offspring exposed to nicotine had fewer blood-forming stem cells, the cells that produce mature effector immune cells and altered patterns of immune regulatory genes within these cells. These changes persisted into adulthood, even though nicotine exposure ended shortly after birth. The findings were published today in Stem Cell Reports .
The immune damage was largely invisible under normal conditions in adult mice. Exposed mice had normal numbers of immune cells circulating in their blood. However, their lungs had fewer resident macrophages,, immune cells that provide an important first line of defense against pathogens. When the PNE mice were later infected with influenza virus, their immune systems responded with increased inflammation and greater movement of immune cells into the lungs. This heightened response resulted in more severe lung damage and greater weight loss.
“This shows how sensitive the developing blood system is to its environment.” said Marcel Rommel, Ph.D. “Blood stem cells set the balance of the immune system, and they carry a memory of what they encountered early in life. An exposure in the first weeks of life can tip that balance in a way that stays hidden until the body faces an infection, and that shapes immune health well into adulthood. The best protection is avoiding nicotine during pregnancy, but we also want to understand whether these changes can be counteracted once they have occurred.”
Smoking during pregnancy is known to negatively affect fetal development, including development of the immune system. Children born to mothers who smoke during pregnancy, for example, are more likely to experience respiratory infections, which can also be more severe.
Tobacco smoke contains many harmful substances in addition to nicotine, making it difficult to determine the effects of nicotine alone. This study helps address that question by isolating nicotine exposure in a mouse model. The findings suggest that nicotine itself can disrupt immune development and have effects that persist long after exposure ends.
“What happens during early development can shape health for a lifetime,” said Taylor Cool, Ph.D. “Our findings show how perinatal nicotine exposure can permanently alter the stem cells responsible for building the immune system. Our study highlights how exposure during this critical window can have lifelong consequences for health.”
While findings in mice do not necessarily translate directly to people, the research raises important questions about nicotine exposure during pregnancy and early development, including through products such as e-cigarettes and nicotine replacement therapies.
About Stem Cell Reports
Stem Cell Reports is the open access, peer-reviewed journal of the International Society for Stem Cell Research (ISSCR) for communicating basic discoveries in stem cell research, in addition to translational and clinical studies. Stem Cell Reports focuses on original research with conceptual or practical advances that are of broad interest to stem cell biologists and clinicians. Stem Cell Reports is a Cell Press partner journal. Find the journal on X: @StemCellReports .
About ISSCR
Across more than 80 countries, the International Society for Stem Cell Research is the preeminent global, cross-disciplinary, science-based organization dedicated to advancing stem cell research and its translation to medicine.
Stem Cell Reports
Perinatal Nicotine Exposure Disrupts Hematopoietic Stem Cell Development and Elevates Influenza Severity in Adulthood
15-Oct-2026