Metagenomic analysis of feces from mice flown on the RR-6 mission

There were two Basal (BSL) groups of animals sacrificed (LAR BSL & ISS-T BSL; N=20; 40 animals; ~36 weeks old) at Kennedy Space Center (KSC; 12/9/17). LAR BSL animals were dissected, and samples were collected upon euthanasia. A Ground Control (GC) group, LAR GC, mimicked the LAR FLT group, which was housed at KSC, then shipped alive, to Novartis’s Facilities, where both the LAR FLT and LAR GC groups were processed (~41 weeks old; 1/16/18).

All were anesthetized with isoflurane, blood samples were obtained by closed-chest cardiac puncture, and the animals were euthanized by exsanguination and thoracotomy. The 20 ISS-T FLT mice were anesthetized via intraperitoneal injection of ketamine/xylazine/acepromazine over the course of a four days of dissections (2/6/18 until 2/9/18; 53-56 days after launch; 44 weeks old at time of on-orbit dissections). Blood samples and euthanasia were conducted the same as LAR groups.

Following blood draw and hind limb dissection, the ISS-T FLT animal carcasses were wrapped in aluminum foil, placed in a ziploc bag and placed in storage at -80˚C or colder until return. The ISS-T Ground Control (ISS-T GC) (at KSC) followed the same euthanasia timeline, methods, and preservation. The final processing of frozen ISS-T FLT, frozen ISS-T GC and frozen 0-day ISS-T BSL animals were completed at Houston Methodist Research Institute, in Houston, TX (5/21/18 until 5/24/18).

GeneLab received feces from only sham treated animals (no drug treated animals) from the following groups. FLT: LAR (n=9), ISS-T (n=7); GC: LAR (N=7), ISS-T (N=9); BSL: LAR (n=7), ISS-T (n=9). DNA was extracted and analyzed by sequencing using a variety of different targeted and un-targeted metagenome profiling assays.