During his PhD studies under Professor Robert Brummer at Örebro University (Sweden) John-Peter set up the Ussing chamber methodology to study the effect of prebiotics on intestinal barrier function. He performed his postdoctoral studies on the epithelial-neuro-immune axis in IBS with Dr Javier Santos and Dr Maria Vicario at Vall d’Hebron Research Institute (Spain). He is now leading the research on gut-brain axis in Parkinson’s disease at Örebro University.