School of Medicine and Health Sciences Poster Presentations

Title

Analysis of Thymus Tissue from Myasthenia Gravis Patients for Survivin Expression

Document Type

Poster

Abstract Category

Neuroscience

Keywords

Myasthenia gravis, Thymus, Germinal center, Neuromuscular, Survivin

Publication Date

Spring 5-1-2019

Abstract

Myasthenia gravis (MG) is an autoimmune neuromuscular disorder caused by autoantibody directed to postsynaptic membrane of the neuromuscular junctions. Early onset MG (EOMG) with autoantibodies to acetylcholine receptor patients often demonstrate thymus pathology of hyperplasia and germinal center formation (GC). Survivin (SVN) is an intracellular protein that belongs to the inhibitor of apoptosis family which has been found to influence apoptosis and proliferation. The purpose of the study is to evaluate thymus from EOMG patients for survivin positive cells and evaluate the expression in the GCs. We investigated the expression of SVN using immunohistochemistry in paraffin-embedded thymus sections from fifteen EOMG patients. The tissue was processed and stained with anti-survivin antibody and scanned into a digital images ‚Äã(Aperio scanner,40√ó) for histological cells analysis using QuPath v0.1.2 ‚Äã. ‚ÄãBy annotating the areas with cells only and excluding other area that contain capsule, fat and connective tissue, images were processed based on the intensity threshold parameter of 0.3. However, due to some variability due to multiple factors include sectioning, staining, tissue condition, the intensity threshold was adjusted and manual counting of multiple random fields was performed to ensure the accuracy of threshold change. Both SVN positive and negative lymphocyte were counted in the tissue field. To count the SVN+ in germinal center (GC), the germinal center were identified by H&E section on serial sectioned slide. Ellipse tool was used to annotate the germinal centers and allow for identification of SVN+ cells. Five thymus samples from EOMG patients did not demonstrate GC in the sectioned area. The higher SVN expression correlated with higher number of GC formation. The thymus sections showed more SVN+ cells in non-germinal center. Sections with minimum thymus content and high fat demonstrated less germinal center formation and higher SVN+ cell ratio. The higher expression of SVN outside GC might suggest a potential anti-apoptotic role. SVN expression could be driving the GC formation or maintenance.

Open Access

1

Comments

Presented at Research Days 2019.

This document is currently not available here.

Share

COinS
 

Analysis of Thymus Tissue from Myasthenia Gravis Patients for Survivin Expression

Myasthenia gravis (MG) is an autoimmune neuromuscular disorder caused by autoantibody directed to postsynaptic membrane of the neuromuscular junctions. Early onset MG (EOMG) with autoantibodies to acetylcholine receptor patients often demonstrate thymus pathology of hyperplasia and germinal center formation (GC). Survivin (SVN) is an intracellular protein that belongs to the inhibitor of apoptosis family which has been found to influence apoptosis and proliferation. The purpose of the study is to evaluate thymus from EOMG patients for survivin positive cells and evaluate the expression in the GCs. We investigated the expression of SVN using immunohistochemistry in paraffin-embedded thymus sections from fifteen EOMG patients. The tissue was processed and stained with anti-survivin antibody and scanned into a digital images ‚Äã(Aperio scanner,40√ó) for histological cells analysis using QuPath v0.1.2 ‚Äã. ‚ÄãBy annotating the areas with cells only and excluding other area that contain capsule, fat and connective tissue, images were processed based on the intensity threshold parameter of 0.3. However, due to some variability due to multiple factors include sectioning, staining, tissue condition, the intensity threshold was adjusted and manual counting of multiple random fields was performed to ensure the accuracy of threshold change. Both SVN positive and negative lymphocyte were counted in the tissue field. To count the SVN+ in germinal center (GC), the germinal center were identified by H&E section on serial sectioned slide. Ellipse tool was used to annotate the germinal centers and allow for identification of SVN+ cells. Five thymus samples from EOMG patients did not demonstrate GC in the sectioned area. The higher SVN expression correlated with higher number of GC formation. The thymus sections showed more SVN+ cells in non-germinal center. Sections with minimum thymus content and high fat demonstrated less germinal center formation and higher SVN+ cell ratio. The higher expression of SVN outside GC might suggest a potential anti-apoptotic role. SVN expression could be driving the GC formation or maintenance.