GVHD reduces chemokine-driven OT-1 effector entry into extravascular BM. (A) Experimental design. (B) Representative images from mice that received transplant with only donor BM (left; supplemental Video 6) and with BM and T cells (BM + T; right; supplemental Video 7). Scale bar represents 50 μm. (C) Quantitation of the E/I ratio and absolute numbers of extravascular and intravascular OT-1 cells. BM alone data are from 14 fields from 6 mice. GVH data are from 9 fields from 6 mice. Significance was determined by a 2-tailed Student t test. ∗P < .001; ∗∗P < .0001.