IgG Hinge Cleavage Strategy to Restore Anti-Tumor Immune Killing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Cancer cells evade host immunity by proteolytically deactivating IgG antibodies, rendering them dysfunctional, which undermines the effectiveness of conventional anti-tumor monoclonal antibody therapies.
Innovation Solution
Utilize the IdeS protease from Streptococcus pyogenes to cleave a single peptide bond in the IgG hinge, exposing a neo-epitope that can be recognized by endogenous anti-hinge antibodies, particularly IgG3, thereby restoring Fc-mediated effector functions and enhancing antibody-dependent cellular cytotoxicity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional monoclonal antibodies are used to treat cancer, then immune effector systems are activated to attack tumor cells, but cancer cells evade immunity by proteolytically deactivating the antibodies
Solution Approach 1:
The patent applies IdeS protease to deliberately cleave IgG antibodies at the hinge region, converting the harmful effect of proteolytic deactivation into a beneficial therapeutic mechanism. The controlled cleavage generates scIgG fragments that expose neo-epitopes, which then recruit endogenous anti-hinge antibodies to mediate enhanced ADCC and CDC against tumor cells.
Solution Approach 2:
The patent changes the structural parameters of IgG antibodies by introducing a single peptide bond cleavage at the hinge region. This structural modification transforms intact IgG into scIgG fragments with exposed neo-epitopes, fundamentally altering the antibody's interaction with the immune system and enabling a new mechanism of action.
2Productivity
If IdeS protease cleaves IgG antibodies, then neo-epitopes are exposed that can be recognized by endogenous anti-hinge antibodies, but the original Fc-mediated effector functions are disrupted
Solution Approach 1:
The patent introduces endogenous anti-hinge antibodies as intermediary molecules that bind to the neo-epitopes exposed on cleaved IgG. These intermediaries restore and enhance Fc-mediated effector functions by providing a new pathway for immune cell recruitment and activation, compensating for the disruption caused by IdeS cleavage.
Solution Approach 2:
The patent segments the IgG antibody structure by cleaving the hinge region, separating the Fc domain from the complete intact structure. This segmentation creates scIgG fragments with exposed neo-epitopes that serve as new binding sites for endogenous anti-hinge antibodies, enabling a segmented approach to restoring antibody function.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The method potentiates cancer cell eradication by leveraging existing IgG3 humoral immunity, amplifying the efficacy of anti-cancer antibodies through the paradoxical induction of proteolytic damage, specifically by enhancing ADCC and CDC mechanisms.
Implementation Method 1
S. pyogenes secretes a protease, IdeS (Immunoglobulin degrading enzyme of Streptococcus pyogenes). This enzyme is inordinately potent and selective in its cleavage of human IgG.
Data Source
AI summary
The present invention relates to methods of treating diseases in a subject in need thereof, including proliferative diseases such as cancer, especially solid tumors, as well as other diseases involving invasive cells or entities such as viruses, bacteria, fungi, and parasites, using IgG antibodies, including anti-tumor IgG antibodies, and a protease from Streptococcus pyogenes.