Maternal farm exposure modulates neonatal immune mechanisms through regulatory T cells

Mike Calvin

Any research co-authored by Erika von Mutius, MD is bound to be interesting. The best articles about the hygiene hypothesis have her fingerprints on them, and if you google her you’ll find all kinds of great information.

The authors of this article ask if life on the farm protects against the development of atopic disease (allergy) and suggest a new means by which maternal farm exposure changes the baby’s immune responses. One fascinating thought is that maternal farm exposure may reflect a “natural model of immunotherapy” potentially including a selection of natural stimuli in addition to allergen, shaping a child’s immune system at an early stage.

Two factors seem to be particularly important for this effect. First, the earlier the influences on the fetus’ immune system, the stronger the effect is on reducing later allergy development, and second, microbial exposure has been identified as a crucial “entity of allergy-protective exposure”. The microbial exposure refers to all the germs found on cows and chickens and other livestock, as well as milk straight from the cow.

The authors found that influences of the farm environment affect this very sensitive period of fetal immune development in such a strong way that it results in long-term immune effects, either through direct or indirect impact on the maternal immune system, maternal-fetal immune interactions or quite likely a combination of both. While it is remarkable that effects before birth are capable of causing a long-lasting immune effect, the underlying mechanism is not understood. Perhaps this “natural model of allergy-protection” will lead to backyard farms cropping up in cities and suburbs.

2009-04-13