Helicobacter pylori - cellular immunity and protection against multiple sclerosis

Multiple sclerosis (MS) is a demyelinating autoimmune disorder affecting the central nervous system (CNS), where inflammatory T-helper 1 (Th1) and Th17 cell responses damage the myelin sheath of neural axons and cause neurodegeneration. The balance between these cells and anti-inflammatory regulatory T-cell (Treg) responses is important in MS development and progression.

H. pylori is a bacterial pathogen that colonises the human stomach from childhood. It is the major cause of peptic ulceration and gastric cancer, however it also induces a potent Treg response and beneficial roles have been described. We were the first to demonstrate protective effects of H. pylori against MS in a mouse model, and reported a lower prevalence of H. pylori amongst MS patients.

This project will evaluate the influence of H. pylori on MS, and investigate the immunological mechanisms. H. pylori status of MS patients will be ascertained by serology, and epidemiological analyses will compare the course of MS in infected and uninfected patients (including disability scores, relapse rates, and responsiveness to therapies). Using flow cytometry and RT-qPCR, we will quantify peripheral blood Treg, Th1 and Th17 cells and investigate differences in their homing receptor expression for migration to the gastric mucosa rather than the CNS.