-Short Review-

Macrophages: Are They Involved in Endometriosis, Abortion and Preeclampsia and How?

Stefan Hutter¹, Sabine Heublein¹, Julia Knabl¹, Ulrich Andergassen¹, Thomas Vrekoussis¹, Antonis Makrigiannakis², Klaus Friese¹, Doris Mayr³ and Udo Jeschke¹

¹Department of Obstetrics and Gynaecology, Ludwig Maximilians University of Munich, Germany
²Department of Obstetrics and Gynaecology, University of Crete, Medical School, Greece
³Department of Pathology, Ludwig Maximilians University of Munich, Germany

Macrophages hold a key role in both regulating and executing the body's own immune response under various conditions. Hence, although endometriosis, preeclampsia and abortions are clinically different, all three are regarded to involve highly complex immunological processes. The aim of our current work was to evaluate the role of macrophages within these gynaecological disorders. Macrophages have been shown to invade endometriosis lesions and to mediate propagation of endometriotic cyst growth. However this is the first time that significant GPER up-regulation in macrophages is demonstrated. This highlights a potential alternative way through which estrogen may modulate immune response of macrophages in endometriosis. In addition, during spontaneous miscarriages the macrophage population increases significantly. This deregulation may possibly support an inflammatory scheme further triggering abortive procedures. Macrophage-mediated apoptosis of extravillous trophoblasts (EVT) has been associated with preeclampsia. Larger numbers of apoptotic EVT were detected in preeclamptic placentas compared with normal. In preeclamptic placentas, decidual macrophages were found to be Fas ligand (FasL)-positive. Our results highlight a new aspect of macrophage biology in endometriosis and pregnancy physiology and patho-physiology. Further studies with larger samples are needed to verify the current results and evaluate their clinical impact. Our data strongly indicate that macrophages hold key roles in various gynaecological disorders and might be crucial to further elucidate their patho-physiology.

J Nippon Med Sch 2013; 80: 97-103

Keywords
abortion, endometriosis, preeclampsia, macrophages, plasticity

Correspondence to
Prof. Dr Udo Jeschke, Department of Obstetrics and Gynaecology, Ludwig-Maximilians-University of Munich, Maistrasse 11, D 80337 Munich, Germany
udo.jeschke@med.lmu.de

Received, November 20, 2012
Accepted, February 8, 2013