Skip to main content
. 2020 Nov 25;23(12):101747. doi: 10.1016/j.isci.2020.101747

Figure 1.

Figure 1

Immune Organs and Total Leukocyte Populations Display Disparities following Simulated Deep Space Exposures

(A) Experimental plan timeline: 15-week-old female C57BL/6J mice were cage acclimated for 3 days (day −3) before experimental initiation (0). Mice were either normally loaded (NL, shaded) or hindlimb unloaded (HU, not shaded) for 14 days. On day 13 mice were whole body irradiated with Sham (0 Gy, green), galactic cosmic rays (GCR, 0.5 Gy, blue), solar particle events (SPE, 1 Gy, red), or gamma (5 Gy, yellow) irradiation types (formulas described in Methods). 24 h post-irradiation (day 14), mice were euthanized and blood and tissues were collected. Body weights were measured on days −3, 0, 7, and 14. Tissue weights were measured on collection day 14.

(B–G) (B) Body weights were measured on days −3, 0, 7, and 14. Immune organ weights of the spleen (C) and the thymus (D) were performed on collection day 14 and normalized to total body weight (g/g). Flow cytometric gating scheme to collect singlets, remove doublets, (“DD” denotes doublet discrimination), and identify CD45+ events (E). Percent (%) (F) and absolute counts (G) of total leukocyte populations (CD45+/all doublet discriminated events, DD) displayed for each exposure group. A Grubbs test was performed on all datasets followed by testing for normal distribution via a Kolmogorov-Smirnov test. If data were normally distributed, a one-way ANOVA Dunnett test was performed to compare NL and HU controls to all groups and a parametric unpaired t test with Welsh's correction was performed to compare between similar irradiation groups. If normality was not passed, both a non-parametric Kruskal-Wallis test with a Dunn's posthoc analysis to compare NL and HU controls with all groups and a non-parametric Mann-Whitney U test comparing between similar irradiation groups were performed. Data in (B) represent a scatterplot. (C and D) Data represent a box-and-whiskers plot with minimum and maximum data points. (F and G) Bar graphs data represent means ± SEM (p < 0.05, n = 8–10 per group). “∗” denotes significant difference between NL-Sham and associated groups, “#” denotes significant difference between HU-Sham and associated groups, and intergroup “brackets with a &” denotes significant difference between each group. Filled circles, boxes, and bars denote normal loaded (NL), and non-filled circles, boxes, and bars denote hindlimb unloaded (HU).