Introduction: There is increasing evidence that allergies, like many other chronic diseases of childhood, may have origins during the prenatal period. It is also known that mothers, have a stronger influence than fathers, on the development of allergic disease in their children. While the mechanisms responsible for this maternal influence are not known, studies have indicated the possibility of transplacental allergen transfer via immunoglobulin G (IgG) containing immune complexes.
Objective: In this study, we investigated the ability of the neonatal Fc receptor for IgG transport (FcRn) to bind and transport the model allergen ovalbumin in the form of an IgG-ovalbumin immune complex.
Methods: Madin Darby Canine Kidney (MDCK) cells stably transfected with FcRn were used in a transcytosis assay to investigate the transport of IgG-ovalbumin immune complexes. Immunofluorescent microscopy and flow cytometry were used to further evaluate the binding of immune complexes to FcRn.
Results: IgG-ovalbumin immune complexes were transported across FcRn-expressing MDCK cells, and the transport was reduced with competitive inhibition and blocking FcRn. In comparison, ovalbumin alone was not transported. Immunofluorescent microscopy and flow cytometry studies showed that IgG-ovalbumin immune complexes bound to MDCK cells and co-localized with FcRn.
Discussion: Our data indicates that FcRn binds to and facilitates the transcytosis of IgG-ovalbumin immune complexes. This supports the notion that allergens can be transported from mother to fetus and possibly contribute to in utero allergic sensitization.
Gazi, Farah, "Human Neonatal Fc Receptor Mediates Transcytosis of Immunoglobulin-G-Bound Ovalbumin" (2016). MCB Articles. 1.