Abstract 2823: Sample storage conditions alter microbiome profiles - its potential relevance for cancer patients undergoing fecal microbial transplants

Background and Objective: Fecal microbiota transplantation helps restore beneficial bacteria in cancer patients after intense antibiotics administration. Here we investigated the influence of different stabilization and storage strategies on the quality and composition of the fecal microbial community. Methods: Same-day isolated murine DNA was compared to samples stored for one month in air at ambient temperature, with or without preservative buffers (i.e. EDTA and lysis buffer), different temperatures (i.e. 4°C, -20°C, and -80°C), and hypoxic conditions. Results: Only storage in lysis buffer significantly reduced DNA content, yet without integrity loss. Storage in EDTA affected alpha diversity the most, which was also reflected in cluster separation. Distinct changes were also seen in the phyla and bacterial species abundance per storage strategy. Metabolic function analysis showed 22 pathways not significantly affected by storage conditions, whereas the tyrosine metabolism pathway was significantly changed in all strategies except by EDTA. Conclusions: Overall, each long-term storage strategy introduced a unique post-collection bias, which is important to take into account when interpreting data. Funded by COBRE P20GM103625. Citation Format: Samir V. Jenkins, Kieng B. Vang, Allen Gies, Robert J. Griffin, Se-Ran Jun, Intawat Nookaew, Ruud Petrus Dings. Sample storage conditions alter microbiome profiles - its potential relevance for cancer patients undergoing fecal microbial transplants [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2823.