Twenty-four hours after the last treatment, EBRT- and sham-irradiated mice from experiment 1 (n = 10) were terminally sedated, and peripheral blood was immediately collected by direct cardiac puncture and transferred into tubes containing 20 µl of 2 mM EDTA and subsequently centrifuged at 13,000 rpm for 6 min in a microcentrifuge. After centrifugation, plasma was removed, aliquoted and immediately stored at −87°C prior to analysis. After collection of peripheral blood, whole brain, spleen, liver and colon were removed and flash frozen in liquid nitrogen prior to quantitative real-time polymerase chain reaction (qRT-PCR) analysis. Plasma inflammatory cytokines and chemokines were measured in duplicate using a bead-based immunofluorescence assay according to the manufacturer’s instructions (cat. no. MPXMCYTO70K; EMD Millipore, Billerica, MA). Data were collected and analyzed using the Luminex-100 system Version IS (Luminex® Inc., Austin, TX). A four or five-parameter regression formula was used to calculate the sample concentrations from the standard curves. Relative IL-1β and TNF-α mRNA levels in these tissues were quantified and normalized to GAPDH gene expression using two-step qRT-PCR as described previously (19 (link)).