The Receptor for the CD200 Tolerance‐Signaling Molecule Associated with Successful Pregnancy is Expressed by Early‐Stage Breast Cancer Cells in 80% of Patients and by Term Placental Trophoblasts

PROBLEM: The CD200 tolerance-signaling molecule that is expressed by a wide variety of tissues, including placental trophoblast and epithelial tumor cells, lacks an intracytoplasmic tail and must act by binding to CD200 receptors that have a limited expression on lymphomyeloid cells. This binding can inhibit inflammation and NK cells, promote macrophage secretion of indoleamine-2,3 dioxygenase (IDO), and promote generation of Treg cells. …