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Updated: Aug 6, 2026
09:04
Activation and Measurement of NLRP3 Inflammasome Activity Using IL-1β in Human Monocyte-derived Dendritic Cells
Published on: May 22, 2014
Conditional activation of IL-12 through a Fibronectin-EDB dependent switch gate
Josephine D Kahn1, Kothai Parthiban2, Peter Slavny2
1Third Rock Ventures, Boston, MA, USA.
Mabs
|July 23, 2026
Summary
Researchers developed a novel antibody format for interleukin-12 (IL-12) to treat solid tumors. This Switch-IL-12 conditionally activates in the tumor microenvironment, reducing systemic toxicity and expanding the therapeutic window.
Area of Science:
- Immunology
- Oncology
- Biotechnology
Background:
- Interleukin-12 (IL-12) is a potent immune-activator with potential for solid tumor treatment.
- High systemic toxicity limits the therapeutic application of IL-12.
- Developing strategies to enhance the therapeutic window of IL-12 is crucial.
Purpose of the Study:
- To engineer a novel, reversible antibody format for conditional IL-12 activation.
- To enable IL-12 activity specifically within the tumor microenvironment.
- To expand the therapeutic index of IL-12 for cancer treatment.
Main Methods:
- Designed a reversible antibody format with a switch arm and targeting arm for conditional IL-12 activation.
- Utilized a dual specificity Fab in the switch arm for competitive binding to IL-12 and Fibronectin-EDB (FN-EDB).
- Employed quantitative systems pharmacology (QSP) modeling and phage screening to generate optimal switch binders.
Main Results:
- Demonstrated FN-EDB dependent Switch-IL-12 activity through in vitro functional assays.
- QSP model refined binding parameters for Switch-IL-12 activity.
- Engineered antibody format shows potential for targeted IL-12 delivery and activation.
Conclusions:
- The novel Switch-IL-12 antibody format allows for conditional activation in the presence of tumor-specific antigen FN-EDB.
- This approach significantly reduces systemic toxicity associated with IL-12 therapy.
- The engineered format holds promise for improving the safety and efficacy of IL-12 in solid tumor treatment.
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