Negative impact of female sex hormones on the anaphylactic response in mice.

Friday, November 08, 2013 — Poster Session IV
2:00 p.m. – 4:00 p.m.	FAES Academic Center (Upper-Level Terrace)	NIAID	IMMUNO-9

Authors

V Hox
A Desai
G Bandaras
MA Beaven
AM Gilfillan
A Olivera
DD Metcalfe

Abstract

Epidemiologic studies have indicated gender differences in the prevalence of allergic diseases with adult women suffering more frequently from anaphylaxis, asthma, urticarial and angioedema. We hypothesized that female sex hormones can alter the course of allergen-induced anaphylaxis in mice and that this effect is mast cell mediated. To test this hypothesis, we induced allergen-dependent systemic and cutaneous anaphylaxis in mice that were either ovariectomized (OVX) or sham-operated. To investigate the role of estrogens, we repeatedly injected naive female mice with the specific estrogen-receptor antagonist ICI 182,780 prior to inducing anaphylaxis. To explore the role of mast cells, histamine levels were measured in plasma after antigen challenge. In vitro, degranulation and cytokine production were measured in mast cells after exposure to estradiol and progesterone. We found that OVX mice were less susceptible to antigen-induced systemic anaphylaxis compared to wild type mice and that prior injection with ICI 182,780 reduced the systemic anaphylactic response. We did not find a direct effect of either estradiol or progesterone on murine mast cells in terms of degranulation. We conclude that female sex hormones have a negative impact on systemic anaphylaxis and that blocking the estrogen receptor can reduce the anaphylactic response in mice.