Additional support for a potential disease‐specific mechanism was observed by Yang et al. when using 1D11 to treat an E‐selectin ligand‐1 KO (Esl1−/−) mouse that had increased TGF‐β activity and severe osteopenia.(6) In this case, after 1D11 treatment, Esl1−/− mice exhibited markedly higher bone volume. The gene discussed is TGFB1; the disease is Osteopenia.