Intact epithelial body surfaces represent physical barriers that protect the organism from invading pathogens and loss of nutrients. This barrier function contributes to intestinal immune homeostasis, which is fundamental for balanced immune responses and protection from overwhelming immune reactions. Irradiation can harm this intestinal barrier function which can lead to side effects after radiotherapy. We want to study fundamental mechanisms of intestinal tissue damage and epithelial regeneration after radiotherapy. We hypothesize that specific diets can influence intestinal tissue damage and regeneration after radiotherapy.