Indicator of Inflammation and NETosis-Low-Density Granulocytes as a Biomarker of Autoimmune Hepatitis

Weronika Domerecka; Iwona Homa-Mlak; Radosław Mlak; Agata Michalak; Agnieszka Wilińska; Anna Kowalska-Kępczyńska; Piotr Dreher; Halina Cichoż-Lach; Teresa Małecka-Massalska

doi:10.3390/jcm11082174

Indicator of Inflammation and NETosis-Low-Density Granulocytes as a Biomarker of Autoimmune Hepatitis

J Clin Med. 2022 Apr 13;11(8):2174. doi: 10.3390/jcm11082174.

Authors

Weronika Domerecka¹, Iwona Homa-Mlak¹, Radosław Mlak¹, Agata Michalak², Agnieszka Wilińska³, Anna Kowalska-Kępczyńska⁴, Piotr Dreher⁵, Halina Cichoż-Lach², Teresa Małecka-Massalska¹

Affiliations

¹ Department of Human Physiology, Medical University of Lublin, 11 Radziwiłłowska Str., 20-080 Lublin, Poland.
² Department of Gastroenterology with Endoscopy Unit, 8 Jaczewskiego Str., 20-090 Lublin, Poland.
³ Department of Clinical Genetics, Medical University of Lublin, 11 Radziwiłłowska Str., 20-080 Lublin, Poland.
⁴ Department of Biochemical Diagnostics, Laboratory Diagnostics, Medical University of Lublin, 16 Staszica Str., 20-081 Lublin, Poland.
⁵ Public Health, Medical University of Lublin, 1 Chodźki Str., 20-093 Lublin, Poland.

Abstract

Introduction. Interest in the potential role of low-density granulocytes (LDGs) in the development of autoimmune diseases has been renewed recently. Due to their pro-inflammatory action, more and more attention is paid to the role of LDGs, including those expressing the enzyme myeloperoxidase (MPO), in the development of autoimmune hepatitis (AIH). LDGs are actively involved in the formation of neutrophil extracellular traps (NETs). This phenomenon may favour the externalization of the autoantigen and lead to damage to internal organs, including the liver. Aim. The main aim of the study was to assess the diagnostic usefulness of the LDG percentage, including the fraction showing MPO expression as markers of systemic inflammation in AIH. Materials and methods. The study included a group of 25 patients with AIH and 20 healthy volunteers. Mononuclear cells, isolated from peripheral blood, were labelled with monoclonal antibodies conjugated to the appropriate fluorochromes (CD15-FITC, CD14-PE, CD10-PE-Cy5, MPO+) and then analyzed on a Navios Flow Cytometer (Beckman Coulter). Results. Patients with AIH had a higher median percentage of LDG (1.2 vs. 0.1; p = 0.0001) and LDG expressing MPO (0.8 vs. 0.3; p = 0.0017) when compared to healthy volunteers. Moreover, the percentage of LDG was characterised by 100% of sensitivity and 55% of specificity (AUC = 0.84; p < 0.0001), while the percentage of LDG expressing MPO was 92% of sensitivity and 55% of specificity (AUC = 0.78; p = 0.0001) in the detection of AIH. Conclusions. Assessment of inflammatory markers, such as the percentage of LDG and the percentage of LDG expressing MPO, may be helpful in assessing the phenomenon of an increased systemic inflammatory response and in assessing liver fibrosis (LC, Liver cirrhosis), which is inherent in liver decompensation. Taking into account the above arguments, the assessment of the percentage of LDG, including LDG expressing MPO, may turn out to be a useful marker in the diagnosis of AIH.

Keywords: LDG; MPO; NET; NETosis; autoimmune hepatitis; inflammation.