E-MEXP-3031 - Transcription profiling by array of M. musculus C57BL/6J mouse white blood cells to investgiate the effect of E. coli and Lactobacillus gasseri innoculation at different dosage on mouse appetite and weight
Released on 31 January 2014, last updated on 2 May 2014
Fifty 8-week-old C57BL/6J mice were randomly divided into five groups of ten mice. The study duration was 28 days and involved three phases, namely an adaptation phase (days 1–7), a treatment phase (days 8-21), and a washout period (days 22-28). During the 14-days treatment period each mouse in the L. gasseri group, the pre-incubation group and the co-incubation group received a daily dose of 1 x 109 viable K7 cells, determined as colony forming units (cfu) on MRS agar, re-suspended in 100 µL of saline solution. The suspension was applied orally by the use of plastic feeding tubes for rodent oral gavage. A single dose of E. coli O157:H7 was applied on day 8 of trial (E. coli group, co-incubation group) and day 15 of trial (pre-incubation group). Each mouse received a dose of 5 x 108 viable E. coli O157:H7 cells, determined as colony forming units (cfu) on E. coli O157:H7 agar, re-suspended in 100 µL of saline solution. The suspension was applied intra-gastrically by the use of plastic feeding tubes for rodent oral gavage. Throughout the three phases of the study the animals were fed ad libitum a standard mouse diet and had access to water at all times. All mice were weighted weekly on days 0, 7, 14, 21, 28. Their feed intake was assessed weekly by measuring the remaining (unconsumed) food. Mice were also monitored twice daily for the clinical status and behavioral changes. End of the study period, mice were euthanized with CO2 and blood samples were obtained from the heart by cardiac puncture. For microarray analysis 300ul of blood from 4 mice in each group were transferred immediately after the cardiac puncture to tubes containing a pre-loaded RNA-later solution.
transcription profiling by array, co-expression, disease state, in vivo