Journal: Molecular Cancer Therapeutics
Article Title: XTX301, a Tumor-Activated Interleukin-12 Has the Potential to Widen the Therapeutic Index of IL12 Treatment for Solid Tumors as Evidenced by Preclinical Studies
doi: 10.1158/1535-7163.MCT-23-0336
Figure Lengend Snippet: Masking of XTX301 activity and reactivation by MMPs in vitro (A) SPR was used to measure the binding kinetics of XTX301, proteolytically cleaved XTX301 (XTX301 + MMP), and rhIL12 to IL12Rβ2. IL12Rβ2 was immobilized to a sensor chip. Then XTX301, proteolytically cleaved XTX301, and rhIL12 were flowed over at concentrations ranging from 3 nmol/L to 400 nmol/L. The concentrations of each analyte decrease from top to bottom within each panel. XTX301 activity was measured in a reporter cell line and primary human cells. B, IL12 HEK-Blue reporter gene cells were incubated with either rhIL12, unmasked control, or XTX301 at varying doses, and the reporter activity was measured. The data represents one of three independent experiments, data points represent the mean of 2 replicate wells and the error bars represent SD. C, Pre-activated primary human PBMCs were incubated with either rhIL12, unmasked control or XTX301 at varying doses, and STAT4 phosphorylation was assessed in CD8 + T cells via flow cytometry. The data points represent the mean of 2 replicate wells and the error bars represent SD. The data represents one of two independent experiments, each conducted with 2 different PBMC donors.
Article Snippet: XTX301, proteolytically activated XTX301, or rhIL12 (R&D Systems, catalog no. 219-IL/CF) were serially diluted and added to the cells and incubated at 37°C in 5% CO 2 for 24 hours.
Techniques: Activity Assay, In Vitro, Binding Assay, Incubation, Control, Phospho-proteomics, Flow Cytometry
