Liver, WAT and BAT from WT and Tg mice which underwent transplantation or sham surgery and rmuFGF21 or vehicle treatment were analyzed histologically and morphologically (Figure S6A–B). The mice generated herein recapitulated the histological phenotypes previously published [18] albeit the livers presented milder hepatosteatosis. The BAT from Tg sham mice contained a heterogeneous population of adipocytes, some with a single, large vacuole and others with a more condensed, eosinophilic cytoplasm containing few, small vacuoles. Cells thought to be macrophages and/or fibroblasts were also present. The WAT from Tg sham mice was composed primarily of adipocytes that varied in size accompanied by scattered cells thought to be macrophages and/or fibroblasts. Livers from Tg sham mice showed swollen hepatocytes reflective of steatosis. Adipose tissue transplantation in Tg mice did not affect the morphology of BAT or WAT; however, the fat accumulation in liver was completely reversed (Figure S6A). Recombinant muFGF21 did not alter the histological phenotypes in WT sham (data not shown), Tg sham nor Tg–tx mice compared to vehicle controls. The lack of any observable difference in adipocyte size in WT
