SLC27A4 and monocytic leukemia: As adult patients with FATP4 mutations manifest allergies and eosinophilia (9), we therefore have been investigating the role of FATP4 in myeloid cells including macrophages (MΦ) since FATP4 is expressed in human monocytes (19), human monocytic leukemia THP-1 cells (20), and mouse bone-marrow-derived macrophages (BMDMs) (21).