Embryos harbor immune cells that already perform adult-like defense functions, study suggests

Researchers from the University of Turku in Finland have discovered that neutrophils, a type of white blood cell, exist in various embryonic tissues during development. These cells, which form the body's first line of defense, have been found to perform the same functions as adult neutrophils. The findings, published in Nature Communications, suggest that embryonic neutrophils play a more active role in tissue development and immune response than previously thought.

Neutrophils are known to rapidly migrate from the bloodstream to tissues to eliminate harmful microbes during inflammation. The researchers used single-cell RNA sequencing, which revealed slight differences in gene expression between embryonic and adult neutrophils. Despite these differences, embryonic neutrophils demonstrated immune functions such as ingesting particles, producing toxic oxygen compounds, and forming weblike structures to trap pathogens.

The study's lead researcher, Laura Lintukorpi, noted that the discovery of neutrophils in multiple developing tissues challenges the understanding of their role during early development. The findings could potentially lead to new treatments for prenatal and perinatal infections and inflammatory diseases if similar cells are found in human tissues.