Fig. 5: Prophylactic vaccination with live-attenuated LmAIO induces strong tumor-specific Th1 immune responses, a pronounced reduction of tumor-specific IgG, decrease in CCA tumor burden and prolonged survival of vaccinated animals.
A Experimental setup to study the prophylactic potential of LmAIO in CCA-Ova settings. B, C Quantification of macroscopic CCA tumor nodules (B) and representative pictures of explanted livers at sampling with indicated tumor burden (C). TNTC, too numerous to count. D, E IFN-ɣ ELISPOT analysis on splenocytes re-stimulated with CD4 and CD8 Ova peptides (D) or oncogenic RASG12V peptides (E). F IL-4 ELISPOT analysis on splenocytes after re-stimulation with Ova protein. G ELISA to detect Ova-specific IgG in serum of vaccinated mice. H–K, Kaplan–Meier survival curves (H, J) and the corresponding intrahepatic tumor counts (I, K) detected in mice which received one (H, I) or two (J, K) doses of prophylactic vaccine. Numbers of animals per group in (B–G) (Ova n = 7, PBS n = 5, LmAI n = 5, LmAIO n = 5), in (H–K) numbers of animals are depicted in the plots. Data were analyzed using unpaired t-test and Mantel–Cox test for survival. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001. Shown are mean ± SEM. SFU, spot-forming units.
