Research Paper Volume 9, Issue 3 pp 706—740

Genomic deletion of GIT2 induces a premature age-related thymic dysfunction and systemic immune system disruption

Figure 1. Genomic deletion of GIT2 attenuates overall murine lifespan and alters thymic T cell functionality. Male and female GIT2KO overall lifespan was assessed through comparison to control wild type (WT) littermates (A). Survival curve analysis of GIT2KO and WT mouse cohorts across their lifespan (B). Representative FACS images of a male WT and GIT2KO thymus at (C) 3 and (D) 12 months of age. The x-axes show increasing c-Kit positive and the y-axes, increasing counts of CD25+ cells. Quadrant 3 (Q3) (bottom R) indicates ETPs (Lin-c-Kit+CD25-), Q2 (top R) indicates DN2 (Lin-c-Kit+CD25+), Q1 (top L) indicates DN3 (Lin-c-Kit-CD25+) and Q4 (bottom L) indicates DN4 cells (Lin-c-Kit-CD25-). Significant age- and GIT2KO-dependent changes (compared to WT) in Lin- (E), ETP (F), DN2 (G), DN3 (H) and DN4 (I) cell counts. GIT2KO mice also demonstrate GIT2KO mice demonstrate significant decreases in DP (J) and CD4+ (K) cell counts at 12 months of age compared to WT. A non-significant trend for a similar reduction in CD8+ cell counts (L) in GIT2KO thymus compared to WT at 12 months of age was observed. Values indicated are mean ± SEM (standard error of mean). WT data are indicated in this and analogous figures with solid lines, GIT2KO data with dashed lines. Months of age is abbreviated to m.o. *p<0.05, **p<0.01.