(A) Representative histograms of LTβ staining in skin CD11b^– DCs (left) and CD11b⁺ DCs (right) from mice treated with BLM for 21–25 days. n = 6 WT mice and 3 Ltb^–/– mice over 3 experiments. (B–D) zDC^DTR/+/WT→WT mixed chimeras (WT) or zDC^DTR/+/Ltb^–/–→WT mixed chimeras (Ltb^–/– ) were injected with BLM over 21 to 22 days, with PBS or DT for the final 1–2 days before skin analysis. (B) DC numbers enumerated by bone marrow donor genotype. Numbers are reported per 8-mm punch. n = 7 chimeras over 5 experiments. (C) ADSC numbers. Left: absolute numbers per punch; right: normalized to PBS groups. n = 8–9 chimeras per condition over 7 experiments. (D) Percentage of ADSCs that are TUNEL⁺. n = 5 chimeras per condition over 5 experiments. (E and F) zDC^DTR/+ chimeras were treated with BLM over 22 days, with PBS or DT for the final 2 days, and with 20 μg anti-LTβR or isotype control 6 hours before the first dose of PBS or DT. n = 4 chimeras per condition over 4 experiments. PBS and DT experiments were performed separately using different batches of chimeras. (E) ADSC numbers. Left: absolute numbers per punch; right: normalized. (F) Percentage of ADSCs that are TUNEL⁺. (G and H) CD31^–CD45^–PDPN⁺DAPI^– cell counts from murine ADSC cultures that were serum-starved and treated with the indicated cells and reagents. (G) Effect on ADSC survival of DCs without or with LTβR-Ig for 48 hours. (H) Effect on ADSC survival of isotype control or agonist anti-LTβR for 48 hours. (I) CD31^–CD45^–PDPN⁺DAPI^– cell counts from human primary ADSC cultures that were serum-starved and treated with isotype control or agonist anti-LTβR for 48 hours. (G–I) Each symbol represents 1 of 3 to 5 experiments with 1 to 3 replicate wells per experiment. *P < 0.05, **P < 0.01, ***P < 0.001 using 2-tailed unpaired Student’s t test. Error bars depict the SEM.