Chimeric Invasin Targeting for Cell-Specific Therapeutic Delivery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current bacterial delivery vehicles lack specific targeting mechanisms, leading to off-target effects and limited cargo capacity, making them unsuitable for clinical translation.
Innovation Solution
Engineering non-pathogenic bacteria to express a chimeric invasin polypeptide with modified binding domains that target specific eukaryotic cells by fusing non-binding domains of Inv with heterologous binding domains or synthetic ligands, allowing precise targeting and intracellular delivery.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If bacterial delivery vehicles use passive mechanisms or ligand-receptor interactions for targeting, then they can deliver therapeutic moieties to target cells, but they exhibit off-target effects to multiple cell types in multiple tissues and organs
Solution Approach 1:
The invasin protein is segmented into functional domains (D1-D5), with D4 and D5 responsible for β1 integrin binding. By replacing only D4 and D5 with heterologous binding domains while retaining D1-D3 for export and uptake functions, the invention achieves specific targeting without off-target effects. This domain segmentation allows precise modification of targeting specificity while preserving essential invasion functions.
Solution Approach 2:
The invention modifies only the specific binding domain regions (D4-D5) of the invasin protein while leaving the export and uptake domains (D1-D3) unchanged. This localized modification approach ensures that the therapeutic bacteria maintain their ability to export and internalize the chimeric invasin while achieving enhanced targeting specificity through the heterologous binding domains, thereby eliminating off-target effects without compromising delivery functionality.
2Manufacturing precision
If bacterial delivery vehicles are engineered with chimeric invasin polypeptides, then targeting specificity is improved, but the complexity of the delivery system increases
Solution Approach 1:
The invention creates chimeric invasin polypeptides by fusing native invasin domains (D1-D3) with heterologous binding domains from other proteins. This composite protein structure combines the export and uptake capabilities of native invasin with the specific targeting能力 of heterologous binding domains, achieving enhanced targeting specificity while maintaining a manageable system complexity through modular domain architecture.
Solution Approach 2:
The chimeric invasin polypeptide serves multiple functions simultaneously: D1-D3 domains handle export to the bacterial surface and stimulation of cellular uptake, while the heterologous binding domain (D4-D5 replacement) provides specific targeting to desired cell types. This multi-functionality within a single protein structure reduces the need for separate components, thereby managing system complexity while achieving precise targeting.
3Manufacturing precision
If viral vectors are used for delivery, then specific targeting can be achieved, but the cargo capacity is extremely limited
Solution Approach 1:
The invention uses bacteria as delivery vehicles that can be genetically engineered to carry and express large amounts of therapeutic cargo, including nucleic acids and proteins. The bacterial system copies and amplifies therapeutic molecules during bacterial replication, providing substantial cargo capacity that exceeds viral vector limitations while maintaining specific targeting through chimeric invasin-mediated delivery.
Data Source
AI summary
A transkingdom platform for the delivery of therapeutics to target cells. The system maintains the export and uptake functions of Inv while modifying its targeting away from β1 integrin to other proteins expressed on the surface of target eukaryotic cells (i.e., a cell surface protein) or chemical moieties (i.e., a cell surface chemical moiety) expressed on the surface of a target eukaryotic cell by replacing D4 and D5 of Inv with a binding domain from a heterologous protein via genetic engineering. These heterologous proteins could be derived from bacterial, fungal, animal, or viral genomes. This engineering would result in the construction of a chimeric Inv protein in which D1-D3 (i.e., the non-binding domains) are fused in frame to an alternative binding domain derived from a heterologous protein. The alternative binding domain would interact with a different cell surface protein or chemical moiety, which can in some instances be referred to as a receptor, on the surface on the surface of a eukaryotic cell, thereby allowing specific targeting to cells independent of Inv's intrinsic β1 integrin binding.