FIGURE 7.
CD4-mediated immune injury requires IFN-γ to skew HSC phenotypes. (A) Representative FACS plots of BM from sublethally irradiated BALB.B mice on day 14 post-HCT that received 3000 WT HSCs alone (n = 3), or HSC+CD4conv taken from WT (n = 5) or IFN-γ−/− (n = 5) C57BL/6 donors. Control recipients were CD45 congenic C57BL/6 mice that received HSC+WT CD4conv T cells (n = 2). BM was analyzed for levels of MPP and true-HSC (ST-HSC and LT-HSC). (B) Bar graphs show percent of MPP (left panel), ST-HSC (middle panel), and LT-HSC (right panel) within the KLS-HSC compartment. Compared with all other groups, only recipients of allogeneic HSC+WT CD4conv had a decreased proportion of MPP and increased proportions of ST-HSC and LT-HSC. *p ≤ 0.05, **p ≤ 0.01.