Fig. 5: MV-BiKE efficacy against patient-derived pancreatic cancer cultures.

A BiKE binding to pancreatic cancer cultures. BiKEs were purified from supernatants of Vero producer cells infected with respective viruses (vBiKEs). Cancer cells were incubated with CEAxCD16A vBiKEs or the HMWMAAxCD16A control. Binding was assessed via flow cytometry based on BiKE labeling with anti-His₆ antibodies. Histograms for PC9 and PC18 are depicted. B, C NK cell cytotoxicity upon vBiKE treatment. Allogenic, IL-2 pre-stimulated NK cells were co-incubated with CFSE-labeled PC9 or PC18 cultures (E:T = 5:1) in presence of vBiKEs (5 ng/µL) for 12 h with subsequent analysis of target cell death via flow cytometry. B Pseudocolor plots exemplarily illustrate gating and CFSE⁺ tumor cell viability for PC18 based on Zombie Violet staining of dead cells. C Target cell death for n = 2 donors with technical duplicates per donor is shown. D–G NK cell activity upon infection of patient-derived cultures with MV-BiKE. Infected cancer cells were cocultured with CFSE-labeled, non-infected target cells and allogenic, IL-2 pre-stimulated NK cells for 12 h (compare Fig. 3A). NK cell degranulation, cytokine expression, and target cell killing were analyzed by flow cytometry. D NK cell degranulation (CD107a) and intracellular IFNγ accumulation in response to MV-BiKE therapy are depicted in exemplary histograms. E Mean percentages of CD107a⁺ and IFNγ⁺ NK cells are shown for n = 6 donors with different symbols representing individual donors. F Pseudocolor plots display the viability of non-infected CFSE⁺ target cells in coculture with respective MV-BiKE infected cancer cells and NK cells. G Mean percentages of target cell death in designated cocultures are summarized for n = 5 donors (PC9, top) and n = 7 donors (PC18, bottom) with donors represented by symbols as in (E). Statistical analysis was performed by one-way ANOVA with Šidák’s multiple comparisons test.