title: Can Colonoscopy Aspirates be a Substitute for Fecal Samples in Analyses of the Intestinal Microbiota?
abstract: There is a growing interest in the study of the human gut microbiota, as correlations between changes in bacterial profiles and diseases are increasingly discovered. Studies in this field generally use fecal samples, but it is often easier to obtain colon content aspirates during colonoscopy. This study used automated ribosomal internal spacer analysis (ARISA) to examine the extent to which the microbiota of colon aspirate samples obtained after bowel cleansing can reflect interindividual differences and serve as a proxy for fecal samples. Pre-bowel preparation fecal samples as well as colonoscopy aspirate samples from the cecum and rectum were obtained from 19 subjects. DNA was extracted from all samples, and comparative analysis was performed, including analysis of similarity (ANOSIM) and nonmetric multidimensional scaling. ANOSIM confirmed that samples from the same individual were well separated from samples from different individuals. Significantly larger differences were found between samples from different individuals than between samples of the same individual (R = 0.7605, p < 0.0001). These findings show that post-bowel preparation aspirates maintain a strong individual signature. Colonoscopy aspirates can therefore serve as a substitute for fecal samples in studies comparing the microbiota of different clinical study groups, especially when fecal samples are unavailable.
authors.affiliation: Department of Gastroenterology and Hepatology, Meir Medical Center, 59 Tshernichovsky St, Kfar Saba, 95847, Israel ; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel.
authors.forename: Nirit
authors.initials: N
authors.lastname: Keren
authors.affiliation: Department of Gastroenterology and Hepatology, Meir Medical Center, 59 Tshernichovsky St, Kfar Saba, 95847, Israel ; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel.
authors.forename: Timna
authors.initials: T
authors.lastname: Naftali
authors.affiliation: Department of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 69978, Israel.
authors.forename: Amir
authors.initials: A
authors.lastname: Kovacs
authors.affiliation: Department of Gastroenterology and Hepatology, Meir Medical Center, 59 Tshernichovsky St, Kfar Saba, 95847, Israel ; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel.
authors.forename: Fred M
authors.initials: FM
authors.lastname: Konikoff
authors.affiliation: Department of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 69978, Israel.
authors.forename: Uri
authors.initials: U
authors.lastname: Gophna
keywords: ARISA; ITS; colonoscopy; inter-individual variation; intra-individual variation; microbiota analysis