Effect of Anti-TNF Monoclonal Antibody on Enteric Neurons and Enteric Glial Cells in Experimental Colitis.

BACKGROUND

Inflammatory bowel diseases (IBD) affect both enteric neurons and enteric glia, with tumor necrosis factor-alpha (TNF-α) playing a role as an inflammatory mediator.

AIMS

Analyze the effects of the anti-TNF monoclonal antibody on the myenteric plexus in an experimental model of colitis.

METHODS

C57BL/6 mice received 3% dextran sodium sulfate (DSS) in drinking water for 7 days in both the DSS and DSS + ADA groups. The Sham group received water. The DSS + ADA group received ADA anti-TNF-α on day 2 of DSS intake. The ADA group was given water throughout the period and received an anti-TNF-α injection on day 2. The study evaluated the number of neurons per ganglion, and the area of the neuronal nitric oxide synthase (nNOS), choline acetyltransferase (ChAT), pan-neuronal marker (PGP9.5), and tumor necrosis factor receptor 2 (TNFR2) immunoreactive (-ir). Double labeling of PGP9.5 with an enteric glial marker (GFAP) was also performed.

RESULTS

DSS successfully induced experimental colitis (EC). TNFR2 was detected in the myenteric neurons in all groups. EC affected the enteric neurons, showing a decrease in the number of TNFR2-ir, ChAT-ir, nNOS-ir, and PGP9.5-ir neurons, whereas enteric glial cells increased in both the DSS and DSS + ADA groups. The DSS + ADA group showed number of nNOS-ir, ChAT-ir, and PGP9.5-ir neurons per ganglion similar to Sham group. EC also affected the neuronal profile, resulting in smaller areas in the DSS and DSS + ADA groups.

CONCLUSION

Myenteric neurons are immunoreactive to the TNFR2. DSS altered the myenteric plexus, and anti-TNF monoclonal antibody treatment proved effective against EC due to preventing the pathology from developing.