Journal: Biomaterials Research
Article Title: PD-L1/Lag3 Bispecific Immune Checkpoint Blocking Nanocage Exhibits Potent Antitumor Activity beyond Dual Blockade of PD-L1 and Lag3
doi: 10.34133/bmr.0362
Figure Lengend Snippet: In vitro binding of PD-L1/Lag3 bispecific ferritin nanocages. (A) MDA-MB-231 cells were incubated with P1, P1L1, P1L2, or wFTH at 4 °C for 1 h. Binding interactions were detected using an anti-ferritin antibody (green), and nuclei were counterstained with DAPI (blue). Scale bars: 30 μm. (B) HEK 293T cells expressing Lag3 were incubated with P1L1, P1L2, L1, L2, or wFTH at 4 °C for 1 h. Binding was visualized using an anti-ferritin antibody (red), GFP-Lag3 expression is shown in green, and nuclei were counterstained with DAPI (blue). Scale bars: 30 μm. (C) Jurkat T cells were stimulated with phorbol 12-myristate 13-acetate (PMA), ionomycin, and chloroquine to express Lag3 followed by incubation with P1L1, P1L2, L1, L2, or wFTH. Bound proteins were measured by anti-ferritin antibody with flow cytometric analysis. Statistical comparisons were conducted with Lag3pep displaying nanocages against wFTH (*** P < 0.001; one-way analysis of variance [ANOVA]); nonsignificant differences are not shown. (D) SPR analysis of Lag3pep-displaying ferritin constructs (L1, L2, P1L1, and P1L2) against Lag3-coated surface. RU were measured at varying protein concentrations to determine binding affinities ( K D ). (E) SPR analysis of P1L2 against PD-L1-coated surface. RU were measured at varying protein concentrations to determine binding affinities ( K D ).
Article Snippet: THP-1 cells expressing human leukocyte antigen-DR isotype (HLA-DR, a subtype of human MHC-II) were used to assess whether Lag3-targeting ferritin nanocages could block interaction between Lag3 and HLA-DR. THP-1 cells were stimulated with 50 ng/ml interferon-gamma (IFN-γ) (PeproTech) for 48 h and then incubated with 400 ng of hLag3-Fc protein (18.3 nM; Acro Biosystems) in the presence or absence of Lag3pep-ferritin nanocages (L1, L2, P1L1, or P1L2; 183 nM) at 4 °C for 30 min. As a positive control, the same molar concentration (183 nM) of anti-human Lag3 blocking antibody (AdipoGen Life Sciences) was used.
Techniques: In Vitro, Binding Assay, Incubation, Expressing, Construct