Study title: Fetal mast cells mediate postnatal allergic responses dependent on maternal IgE Science, Oct 29, 2020
This interesting new animal study shows that the IgE antibodies responsible for allergic reactions can be transferred across the placenta to the fetus. The babies then develop allergies at the first exposure to the allergen.
The study used mice that were highly allergic to ragweed pollen before pregnancy, and thus would have high levels of IgE antibodies to the pollen. The baby mice then were born with a ragweed allergy, triggering mast cell release in response to only ragweed. BUT – the allergy did fade after about 6 weeks.
The researchers also determined that the FcRN protein is necessary for the transfer of the IgE antibody across the placenta. FcRN is a cellular receptor that is active in the placenta, transporting the mother’s IgG antibodies to the fetus. There are a number of studies going on regarding FcRN, IgG and autoimmune diseases.
Why is this interesting to me?
There is a lot of potential here to apply this knowledge to infants that have early allergies that show up as eczema. Perhaps looking at what a mother is allergic to could help to prevent the infant and toddler allergy response.
Here is a good overview article explaining the Science study: https://medicalxpress.com/news/2020-10-mothers-allergies-offspring-preclinical.html