TLR1/2 agonist treatment is associated with decreased bone marrow SECs. Wild-type mice were treated with PAM₃CSK₄ (100 μg, every other day × 3 doses) and analyzed 24 hours after the final dose. (A) Representative images of femur sections stained for vascular endothelial–cadherin (VE-cad; red) and 4′,6-diamidino-2-phenylindole (DAPI; blue). (B) Quantification of the VE-cad signal by histomorphometry. (C) Representative flow plots showing gating strategy to identify CD31⁺ Sca1^– CD45^– Ter119^– SECs and CD31⁺ Sca1⁺ CD45^– Ter119^– AECs. Quantification of SECs (D) and AECs (E). Data represent the mean ± standard error of the mean. Statistical significance determined by using an unpaired t-test. ∗P < .05, ∗∗P < .01.