A subset of adipose transplants from wildtype mice were excised to evaluate success of the tissue grafts (Figure S6B). Adipocytes were separated by cells that were thought to be macrophages and/or fibroblasts (Figure S6A). All or large portions of the explants appeared viable with the exception of one mouse in which the transplant was hemorrhagic and calcified. The data from this mouse were excluded from the study. Compared to our transplantation pilot study (Figure S4) we observed increased inflammation and more heterogeneity in adipocyte sizes in the explants from the current study. We attribute this to the difference in the 2 study designs; the pilot mice were transplanted and left to recover for 4 weeks, whereas the mice presented in Figure 4 were handled twice daily for injections and for regular measurements. This additional handling likely disturbed the grafting process of the transplanted WAT. Nonetheless we still had successful transplantation due to several results, namely, steatosis and liver weights were much improved (Figure S5D, S6), plasma glucose and NEFAs were improved (Figure S5A–B), as were insulin, cholesterol and triglycerides (Figure 4I, K–L). Thus we concluded transplantation was successful. Recombinant muFGF21 did not alter the appearance of the WAT explants.
