Spatial Analysis of the Intestinal Microbiota in Healthy Subjects

The investigators aim to evaluate complete colonoscopies from 10 healthy subjects. This study is used as a first explorative study of how the human gut microbiota is distributed along the lower gastrointestinal tract. No comparable studies in an uncleansed bowel have been performed so far. The number of subjects is based on other studies investigating the microbial composition of mucosal- and faecal-associated microbiota in which a sample size of 10 was enough to detect a difference. An equal number of men and women will be recruited. Drop-outs will be replaced.

Inclusion criteria

• Signed informed consent
• Age: 18-65 years

Exclusion criteria

• Known organic gastrointestinal disease (e.g. inflammatory bowel disease, irritable bowel syndrome, chronic diarrhoea or constipation)
• History of or present gastrointestinal malignancy or polyposis
• Recent (gastrointestinal) infection (within last 6 months)
• History of major gastrointestinal surgery (e.g. gastric bypass)
• Eosinophilic disorders of the gastrointestinal tract
• Current communicable disease (e.g. upper respiratory tract infection)
• Malignant disease and/or patients who are receiving systemic anti-neoplastic agents
• Psychiatric diseases (e.g. dementia, depression, schizophrenia, autism, Asperger Syndrome) or other incapacity for adequate cooperation
• Chronic neurological/neurodegenerative diseases (e.g. Parkinson's disease, multiple sclerosis)
• Autoimmune disease and/or patients receiving immunosuppressive medications
• Major relevant allergies (e.g. food allergy, multiple allergies)
• Chronic pain syndromes (e.g. fibromyalgia)
• Chronic fatigue syndrome
• Obesity (body mass index>30) or metabolic syndrome
• Antimicrobial treatment or prophylaxis within the last 3 months
• Other chronic use of drugs that may affect the microbiome, e.g. proton pump inhibitors
• Females who are pregnant or breast-feeding
• Known clinically significant abnormal laboratory values
• Abuse of alcohol or drugs
• Probiotic intake within the last 6 weeks
• Bowel cleansing within the last 6 months
• Any clinically significant disease/condition which in the investigator's opinion could interfere with the results of the trial