Table of Contents Author Guidelines Submit a Manuscript
Mediators of Inflammation
Volume 2018, Article ID 7041342, 12 pages
Research Article

The Increase of Circulating PD-1- and PD-L1-Expressing Lymphocytes in Endometriosis: Correlation with Clinical and Laboratory Parameters

1I Department of Gynecology, Medical University of Lublin, 16 Staszica Street, 20-081 Lublin, Poland
2Department of Clinical Immunology and Immunotherapy, Medical University of Lublin, 4a Chodzki Street, 20-093 Lublin, Poland
3Department of Pharmaceutical Microbiology with Laboratory for Microbiological Diagnostics, Medical University of Lublin, 1 Chodzki Street, 20-093 Lublin, Poland
4Augusta Kliniken Bochum, 26 Bergstrasse Street, 44791 Bochum, Germany

Correspondence should be addressed to Ewelina Grywalska; moc.liamg@akslawyrg.anilewe

Received 26 May 2018; Accepted 27 September 2018; Published 25 November 2018

Academic Editor: Carla Pagliari

Copyright © 2018 Monika Walankiewicz et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The cause of endometriosis remains unknown. However, studies investigating the link between this condition and the immune system revealed several immunological abnormalities focused on cell-mediated immunity. As a major immune checkpoint, programmed cell death protein 1 (PD-1) displays an important inhibitory function in the maintenance of peripheral tolerance. The expression of PD-1 and its ligand (PD-L1) may contribute to continuous T cell activation and development of inflammation and injury of the tissue. To our knowledge, this is the first study evaluating frequencies of PD-1-positive T CD3+ cells (CD4+ and CD8+) and B cells (CD19+) in patients with endometriosis. Peripheral blood (PB) samples from 25 female patients and 20 healthy age and sex-matched subjects serving as controls were used in the study. Using flow cytometric analysis, we assessed the differences in the frequencies of PD-1-positive T and B lymphocytes in the study group and healthy individuals. Alteration of the PD-1/PD-L1 axis may contribute to the pathogenesis of endometriosis, as patients with advanced disease are characterized by higher frequencies of PD-1-positive T and B cells. Expression of PD-1 and PD-L1 on T and B cells could represent the hallmark of immune system reaction to chronic antigenic exposition in patients with endometriosis.