Figure 4: Characterization of in vivo p-HEAL implant survival and rodent Plasmodium liver stage infection in vivo.

(A) (left) Schematic of humanization of mice with p-HEALs and liver stage Plasmodium infection. (right) Schematic of non-overlapping regions of interest for BLI measurements of Pb-GFP-luc or Py-luc infection in either the mouse liver or the implanted p-HEAL in p-HEAL-humanized mice after intragraft injection with either Pb-GFP-luc or Py-luc spz. (B) Representative BLI image of nude mice that received p-HEALs (HEP + FIB) or PEG cryogels with FIB only at D12 post-implantation. Prior to encapsulation, HEPs were transduced with a human albumin-driven lentiviral firefly luciferase (Lenti-Alb-Fluc) reporter. (C) Cumulative BLI signal from Lenti-Alb-Fluc reporter in mice shown in (B) over the course of 3 weeks post-implantation in vivo. BLI signals were measured every 2 or 3 days. *p < 0.05, two-tailed t-test. n = 3. (D,E) p-HEALs humanized mice were injected with 1.5 × 10⁵–5 × 10⁵ Pb-GFP-luc spz D5 post-implantation, and liver stage infection was measured by BLI at 24 h and 48 h post-infection. The dashed line (—) represents the background BLI signal from the implant site of mice that received acellular PEG cryogel implants and were subsequently injected with infectious Pb-GFP-luc sporozoites (Implant control). **p < 0.01, Mann-Whitney test. n = 5, 6, 17, 17 for mock infected 24 h, mock infected 48 h, infected implant 24 h and infected implant 48 h, respectively; n is cumulative from 4 experiments performed on separate days. (F,G) p-HEALs humanized mice were infected with 9 × 10⁵ Py-luc spz D5 post-implantation, and infection was measured by BLI at 48 h post-infection. *p < 0.05, Mann-Whitney test. n = 3, 7 for mock infected and infected implant, respectively. Error bars represent SEM.