Bern Human Organoid-Study to Study Host-microbe Interaction

Inclusion Criteria: * Signed informed consent * Indication for upper or lower endoscopic procedure * Ability to understand and follow study procedures and understand informed consent * Age 18-80 years * Negative pregnancy test result prior to study enrollment of female study participants (test will be performed prior to enrollment) * BMI between 18.5 and 30 kg/m2 Exclusion Criteria: * Disease known to chronically affect gut microbiota, gut epithelium or gut-associated immune system, namely inflammatory bowel disease, diverticulitis, microscopic colitis, liver cirrhosis, malignancy within the digestive tract, systemic sclerosis, coeliac disease, common-variable immunodeficiency, diabetes mellitus * Medication with immunosuppressants (e.g. corticoids, biological therapy) * Current diagnosis of a hematological disorder (e.g. anemia with hemoglobin \<7 g/dl, leukemia) or any other absolute contraindication for blood draw * Women who are pregnant * Serious coagulation disorder, relevant thrombocytopenia (\<50'000/ul), double platelet-inhibition, oral anticoagulation (ASS therapy is possible) * Known or suspected non-compliance, drug, or alcohol abuse * Inability to follow the procedures of the study, e.g., due to language problems, psychological disorders, dementia, etc. of the participant * Previous enrolment into the current study * Enrolment of the investigator, his/her family members, employees, and other dependent persons * Inability or unwillingness to provide blood samples and tissue samples (biopsies) * Participants taking oral anticoagulant or with bleeding disorders who would be at much higher risk of bleeding after biopsy samples or who are contraindicated for an endoscopic examination * Patients unable to give informed consent * Patients that have been under antibiotic therapy in the last 4 weeks * Participation in other clinical study interfering with study procedures * Potential study participants that wish not to be informed about random results acquired during the study (e.g., during endoscopy or genetic analysis) relevant for their health and for prevention of diseases