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

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.

Myeloid-derived suppressor cells in ovarian cancer: friend or foe?

Although previous decades contributed to major progress in targeted therapy of many malignancies, the treatment of gynaecological cancers remains a challenging task. In the evidence of rising cancer mortality, the search for new methods of treatment is a dire need. Exploring the mechanisms of interaction between tumour cells and host immune response may allow the introduction of new, effective therapies - not as toxic and far more efficient than conventional methods of cancer treatment. Epithelial ovarian cancer (EOC) is typically diagnosed at advanced stages. Its incidence and mortality rate is high. Powerful diagnostic tools for this kind of cancer are still under investigation. Multiple mechanisms existing in the ovarian tumour network create a specific immunosuppressive microenvironment, in which accumulation of myeloid-derived suppressor cells (MDSCs) may be a critical component for diagnosis and treatment. This review attempts to verify current knowledge on the role of MDSCs in EOC.

Influence of fingolimod on basic lymphocyte subsets frequencies in the peripheral blood of multiple sclerosis patients - preliminary study.

BACKGROUND: Fingolimod is a drug administered orally to adult patients treated for relapsing remitting course of multiple sclerosis (MS). Mode of action of fingolimod is based on intense S1P1 receptor stimulation and "arresting" lymphocytes in lymphatic organs. Objective of the research was to assess changes in the frequencies of basic lymphocyte subsets in patients treated for multiple sclerosis with the use of fingolimod. MATERIAL AND METHODS: Study group comprised of 25 previously untreated adult patients with MS. Venous blood samples were collected from each patient before and one month, three months and six months after treatment initiation. Peripheral blood lymphocyte immunophenotype was assessed with a set of monoclonal antibodies bounded to appropriate fluorochromes and flow cytometer FACSC alibur. Statistical analysis of the results was conducted using Statistica 9.0 software. RESULTS: Before fingolimod administration median of lymphocyte subsets percentage in each patient was in reference range. After 1 month of treatment we noticed significant changes in frequencies of following lymphocyte subsets: NK cells - 51.22% (p = 0.016), T CD4+ cells - 11.58% (p = 0.01), T CD4+:T CD8+ cells ratio - 0.61 (p = 0.005). After 3 and 6 months of treatment there was further increase of deviation from normal state. CONCLUSIONS: The use of fingolimod is associated with profound changes in lymphocyte subsets distribution, which might bear a risk of the development of cellular immune deficiency symptoms.