P071 T-cell, B-cell and monocytic infiltrations of myenteric plexus in IBD

Abstract Background Patients suffering from IBD frequently suffer chronic visceral pain, severely affecting quality of life. To better understand factors impacting pain signaling by enteric nervous system (ENS) neuronal cells, we analyzed the infiltration myenteric plexus (MP) ENS inflammatory cell populations. In detail, characterized (i) immune populations infiltrating MP, (ii) neurotransmitter expression MP cells and (iii) survival in Crohn’s disease (CD) ulcerative colitis (UC). Methods We included 12 UC nine CD patients that received colectomies or ileocecal resections, respectively, 10 control with surgeries for non-inflammatory reasons. FFPE material was used immunohistochemistry analysis MP. Immunostaining performed detection neurons (beta-III tubulin, PGP9.5), T-cells (CD3, CD4, CD8 FOXP3), B-cells (CD20), monocytes (CD68, CD163) apoptosis (Annexin V) neurotransmitters CGRP substance P. Intraganglionic periganglionic were determined conventional LSM confocal microscopy. Results CD3+ CD8+ intraganglionic (CD3+: 1.7 ± 0.6 cells/10.000 µm²; CD8+: 4.8 1.1 µm²) found to be increased compared 0.2 0.1 µm², p=0.04; 0.4 p=0.006), Figure 1. CD20+ CD68+ significantly as well (CD20+ CD: 0.8 controls: 0 µm, p=0.02), 12.3 3.5 p=0.001). cytotoxic area UC. 1.6-fold detected p=0.01. Substance P 0.7-fold reduced MP-cell p=0.048. 2 shows representative immunostainings two per condition. Conclusion conclusion, infiltrations are comprised CD3+, B-cells. Specifically periganglionically, The is CD-MPs whereas levels UC-affected MPs revealed higher apoptosis.