SAT387 Impact Of Genetic Background On Chronic Inflammation In A Letrozole-induced Mouse Model Of PCOS

Abstract

Abstract Disclosure: N. Ujagar: None. G. De Robles: None. L. Velez: None. M. Seldin: None. D. Nicholas: None. The etiology behind polycystic ovary syndrome (PCOS) is elusive due to the heterogeneity of its symptoms and varying severity in patients. There are a wide variety of factors associated with PCOS, like hyperinsulinemia, hyperandrogenism, endotoxemia and chronic inflammation that have been implicated as causal factors in the condition. However mechanisms of cause and effect are difficult to establish in human cohorts. Endotoxemia, observed in humans and mouse models of PCOS, is known to trigger chronic inflammation by activating immune cells. Although correlation of chronic inflammation with PCOS has been established, the type of inflammation in PCOS patients has not been defined, in part due to the genetic variance from person to person. Using a systems immunology approach to mimic human genetic diversity, combined with a letrozole-induced PCOS mouse model, we aim to distinguish the types of inflammation present in PCOS. We analyzed the immune cells from lymph nodes and spleens of 21 different strains of PCOS induced and control mice (130 mice in total), and found that based on genetic background the reproductive and metabolic phenotypes differed- similar to how PCOS presents clinically. Splenocytes from these control and PCOS mice were activated in vitro to trigger T cell and myeloid cell cytokine secretion, which was measured via luminex. Clustering analysis of these multi-analyte cytokine measurements together with flow cytometry of the immune cells allowed us to identify T-helper 17 (Th17) cells as the prominent immune cell driving inflammation in letrozole-induce mouse model of PCOS independent of genetic background. This systems immunology approach has allowed us to define PCOS associated inflammation and will be the basis for integrating human inflammation in PCOS with mouse models that appropriately recapitulate disease. The discovery of Th17 cells as key inflammatory mediators provide targets for understanding the mechanisms linking chronic inflammation to reproductive and metabolic outcomes in PCOS, and will assist in future development of anti-inflammatory therapies. Presentation Date: Saturday, June 17, 2023