Medizinische Universität Graz Austria/Österreich - Forschungsportal - Medical University of Graz
Gewählte Publikation:
Himmer, N.
Analysis of the JAK-STAT signaling pathway in leucocytes.
Humanmedizin; [ Diplomarbeit ] Graz Medical University; 2020. pp. 109
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- Autor*innen der Med Uni Graz:
- Betreuer*innen:
- Fessler Johannes
- Stradner Martin Helmut
- Altmetrics:
- Abstract:
- 1Abstract 1.1Introduction Rheumatoid arthritis (RA), is a chronic inflammatory disorder and the most common autoimmune-rheumatic disease. As a clinical syndrome, several types of inflammatory cascades lead to a common pathway with persistent synovial inflammation and defect to articular cartilage as well as underlying bone. Main clinical symptom is a progredient polyarthritis, other symptoms may differ, depending on location and stage of RA. Untreated, disease progression leads to joint destruction, disability and systemic manifestation. While the pathogenesis of RA is not jet fully understood, cytokines and the JAK-STAT signaling pathway play an important role in RA. The intention of the study was, to establish a laboratory protocol and procedure in order to analyse the phosphorylation of STAT-molecules in leucocytes. Therein, we aimed to identify potential variations between patients with rheumatoid arthritis and healthy subjects. We also planned to analyse whether certain endotypes exist within the subjects collective. 1.2Material and Methods: In a prospective study peripheral blood from 17 patients with RA and 6 healthy controls was analysed. Phosphorylation of STAT-proteins was examined via measuring the mean fluorescent intensity (MFI) in leucocyte populations with flow cytometry. Subjects blood was analysed both unstimulated and stimulated with cytokines prior to flow cytometric analysis. We compared the MFI of lymphocyte subsets with hierarchical clustering and identified parameters responsible for clustering. Additionally, findings were compared to subject’s cytokine levels. 2.3Results and Discussion We found significantly increased phosphorylation of STAT3 in different cell types in RA subjects, compared to healthy subjects. Increase also concerned phosphorylation of STAT4 and STAT5 to a lesser extent. Overall STAT-phosphorylation did not allow for a clear separation of healthy subjects and subjects with RA in hierarchical cluster analysis. Yet, distinct distribution in the expression of STAT-phosphorylation allowed for the overall classification of all subjects into subgroups. While these findings show a heterogenous expression of STAT-molecules, endotypes within the RA-collective were not found significantly. Still, results might be of interest in the understanding of RAs and its treatment. As our subjects’ collective was relatively small compared to the number of analysed variables, further expansion of the collective is reasonable.