Journal: iScience

Article Title: Synthetic zipper mediated pre-targeting system for near-infrared photoimmunotherapy

doi: 10.1016/j.isci.2025.114558

Figure Lengend Snippet: Specific interaction of scFv-Zip2 and Zip1-SNAP and their binding specificity in ovarian cancer cells (A) IR700 fluorescence was visualized using an Odyssey DLx Imager after incubation of scFv-Zip2 fusion proteins (scFv-Farletuzumab-Zip2, scFv-Sacituzumab-Zip2, and scFv-Tisotumab-SNAP-Zip2) with Zip1-SNAP-IR700. The scFv-Farletuzumab-SNAP was used as a control to assess the specificity of synthetic zipper interactions. (B) Flow cytometry analysis confirmed the antigen-specific binding of the pre-targeting complex in ovarian cancer cell lines. Histograms show the binding of scFv-Farletuzumab-Zip2 + Zip1-SNAP-IR700, scFv-Sacituzumab-Zip2 + Zip1-SNAP-IR700 and scFv-Tisotumab-Zip2 + Zip1-SNAP-IR700 to FOLR1 + , TROP2 + , and TF + ovarian cancer cells. (C) scFv-Zip2 and Zip1-SNAP were conjugated with 488 and IR700 respectively. We showed only IR700 channel to visualize only the Zip1-SNAP-IR700 florescence signal and finally merged to 488 and DAPI to visualize the internalization. Fluorescence microscopy images showing co-localization of scFv-Farletuzumab-Zip2 labeled with Alexa Fluor 488 and Zip1-SNAP-IR700 on ovarian cancer cells at 4°C, confirming the specific cell surface interaction of the pre-targeting complex. Scale bars, 25 μm.

Article Snippet: After incubation with SNAP-Surface® Alexa Fluor® 488 (New England Biolabs, Ipswich, MA, USA) for 20 min at room temperature in the dark, the fractions were subjected to 10% SDS-PAGE to verify SNAP-tag activity and protein presence, followed by Coomassie Brilliant Blue staining.

Techniques: Binding Assay, Fluorescence, Incubation, Control, Flow Cytometry, Microscopy, Labeling

Journal: iScience

Article Title: Synthetic zipper mediated pre-targeting system for near-infrared photoimmunotherapy

doi: 10.1016/j.isci.2025.114558

Figure Lengend Snippet: Specific binding and co-localization of pre-targeting complex (A) Cells were incubated with Alexa Fluor 488-labeled (A) scFv-Sacituzumab-Zip2 and (B) scFv-Tisotumab-Zip2, followed by treatment with Zip1-SNAP-IR700. Fluorescence microscopy at 4°C revealed specific binding and co-localization of the scFv-Zip2 constructs with Zip1-SNAP-IR700, confirming zipper-mediated interaction and spatial overlap of the pre-targeting components. Scale bars, 25 μm.

Article Snippet: After incubation with SNAP-Surface® Alexa Fluor® 488 (New England Biolabs, Ipswich, MA, USA) for 20 min at room temperature in the dark, the fractions were subjected to 10% SDS-PAGE to verify SNAP-tag activity and protein presence, followed by Coomassie Brilliant Blue staining.

Techniques: Binding Assay, Incubation, Labeling, Fluorescence, Microscopy, Construct