Maternal- and Fetal-Encoded Perforin-2 Limits Placental Infection by a Bloodborne Pathogen.

In this study, we analyzed perforin-2 activity in the mouse placenta to determine whether perforin-2 plays a similarly protective role. We show that perforin-2 is critical for inhibiting Listeria monocytogenes colonization of the placenta and fetus and that this protection is due to both maternal and fetal-encoded perforin-2. Perforin-2 mRNA is readily detectable in individual immune cells of the decidua, and these levels are further enhanced specifically in decidual macrophages during high-dose infections that result in fetal expulsion. Unexpectedly, inductive perforin-2 expression in decidual macrophages did not occur during milder infections in which fetal viability remained intact. This pattern of expression significantly differed from that observed in splenic macrophages in which inductive perforin-2 expression was observed in both high and mild infection conditions. In the placenta, inductive perforin-2 expression in decidual macrophages was coincident with their polarization from a CD206+ MHC class IIlo to CD206- MHC class IIhi phenotype that normally occurs in the placenta during high-burden infections. Our results suggest that perforin-2 is part of a host response that is protective either for both the mother and fetus in milder infections or exclusively for the mother during high-dose infections. PMID: 32839236 [PubMed - as supplied by publisher]
Source: Journal of Immunology - Category: Allergy & Immunology Authors: Tags: J Immunol Source Type: research