Fig. 4: Heterotopic implantation of co-culture BELs in a large animal model.

a Schematic of heterotopic BEL implant surgical model. See text for details. b Post-operative 3D-reconstruction from CT imaging demonstrating BEL perfusion and devascularization of native liver. BEL is outlined in yellow and native liver is outlined in green. c Representative axial CT imaging of recipient animal at post-op, 24 h, and 48 h time points. BEL is outlined in yellow. d Kaplan–Meier curves showing animal survival times within portocaval shunt and BEL implant groups. Symbols are matched to ammonia values in (d). e Post-operative blood ammonia levels measured in BEL implant recipient animals (n = 3) and portocaval shunt animals (n = 2) over the duration of the experiment. Asterisks (*) denote data points that were above the upper limit of quantification of the assay (1 mM). f, g Representative histological section of BEL tissue explanted 48 h post-implant showing viable hepatocytes and endothelialized vasculature. h, i Representative immunostaining BEL tissue (h) pre-implant and (i) explanted 48 h post-implant showing maintenance of CD31 and albumin expression. j, k Representative immunostaining BEL tissue (j) pre-implant and (k) explanted 48 h post-implant showing maintenance of CD31 and FAH expression. l, m Representative immunostaining BEL tissue (l) pre-implant and (m) explanted 48 h post-implant showing maintenance of CYP3A4 expression. HA—hepatic artery; BEL—bioengineered liver; P/C—portocaval; CT—computed tomography; FAH—fumarylacetoacetate hydrolase; CYP3A4—cytochrome p450 3A4.