Neutrophil depletion retards endometrial repair in a mouse model

Abstract

The contribution of the high abundance of inflammatory cells present in the human endometrium prior to and during menstruation is unknown with respect to endometrial repair and/or menstruation. In this study, the presence and localisation of markers for key inflammatory cells have been examined in a mouse model of endometrial breakdown and repair and the functional contribution of neutrophils has been determined. In the model, decidualisation is artificially induced and progesterone support withdrawn; the endometrial tissue progressively breaks down by 24 h after progesterone withdrawal and, by 48 h, has usually undergone complete repair. Neutrophils have been identified in low abundance in decidual tissue, rise in number during breakdown and are most abundant during early repair. Macrophages are barely detectable during breakdown or repair in this model, whereas uterine natural killer cells are found only in intact decidua. The functional contribution of neutrophils to endometrial breakdown and repair has been assessed via neutrophil depletion by using the antibody RB6-8C5. This antibody significantly depletes neutrophils from the circulation and tissue, affects endometrial breakdown and markedly delays endometrial repair. This study has therefore demonstrated that neutrophils are the most abundant leucocyte in this model and that they play an important functional role in the processes of endometrial breakdown and repair.

Molecular regulators of resolution of inflammation: potential therapeutic targets in the reproductive system

“…The role of resolution mediators in restoration of endometrial tissue homoeostasis leading to scarless healing following menstruation is currently unknown. However, post-menstrual repair is delayed following neutrophil depletion in a mouse model revealing a role for these cells in resolution potentially via LOX enzyme expression (Kaitu'u-Lino et al 2007).…”

Identification of a Novel Neutrophil Population: Proangiogenic Granulocytes in Second-Trimester Human Decidua

“…Similar processes have been suggested in the stabilization of murine endometrial blood vessels after menstruation. Neutrophils expressing VEGF are observed in association with angiogenic endothelial cells, and depletion of neutrophils retards endometrial repair (52).…”

Estrogen Receptors in Leukocytes - Possible Impact on Inflammatory Processes in the Female Reproductive System

“…Neutrophils are present in large numbers during endometrial repair and play an important role. In a mouse model designed to mimic the events of menstruation, it was observed that when neutrophils were depleted, endometrial regeneration was severely affected suggesting that neutrophils along with the regulatory factors they produce contribute to the tissue repair (Kaitu'u-Lino et al, 2007). Macrophages, eosinophils and lymphocytes could also contribute in this process .…”