Antibody Multimer Fusion Expression via Stoichiometric Cassette Ratios
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The production of complex polypeptides like antibody-multimers faces challenges in achieving efficient expression and correct assembly due to the complexity of controlling the expression ratios of different polypeptide chains, which is crucial for high yield and product quality, especially in recombinant mammalian cell systems.
Innovation Solution
A method involving the transfection of mammalian cells with a defined stoichiometric ratio of expression cassettes for the antibody heavy chain, light chain, and fusion polypeptides, specifically a 1:1:2:1 ratio, to facilitate the production of antibody-multimer-fusion polypeptides, which can be either transiently or stably expressed, using vectors that may include single or multiple expression cassettes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If random integration of nucleotide sequence is used, then cell line generation is simple, but control of expression ratio of different polypeptide chains is poor
Solution Approach 1:
The invention divides the expression control into separate modular elements: individual expression cassettes for each polypeptide chain, each with its own promoter and regulatory elements. This segmentation allows independent optimization of each cassette's expression characteristics while maintaining overall coordination through the defined stoichiometric ratio of 1:1:2:1 for heavy chain:light chain:first fusion polypeptide:second fusion polypeptide.
Solution Approach 2:
The invention changes the critical parameter of expression ratio control by specifying precise stoichiometric ratios (1:1:2:1) for the different polypeptide encoding cassettes. This parameter specification enables correct assembly of the antibody-multimer-fusion by ensuring appropriate amounts of each polypeptide chain are produced, directly addressing the manufacturing precision issue.
2Manufacturing precision
If targeted integration by RMCE is used, then expression ratio control is improved, but cell line generation complexity increases
Solution Approach 1:
The invention performs preliminary action by pre-defining the stoichiometric ratio (1:1:2:1) and pre-designing the expression cassettes with appropriate promoters and regulatory elements before transfection. This preliminary planning simplifies the actual cell line generation process by providing a clear roadmap for achieving the desired expression pattern, thereby reducing the complexity despite using targeted integration methods.
Solution Approach 2:
The invention creates universal expression cassettes that can be applied across different cell line generation scenarios. The standardized cassette design with defined ratios serves multiple purposes: controlling expression levels, ensuring correct assembly, and facilitating scalable production. This universality reduces the need for custom-designed integration strategies for each application.
3Reliability
If defined stoichiometric ratio of expression cassettes is used, then assembly correctness is improved, but transfection complexity increases
Solution Approach 1:
The invention merges the control of multiple polypeptide expressions into a single coordinated system by using defined stoichiometric ratios (1:1:2:1) that simultaneously govern the production of heavy chain, light chain, first fusion polypeptide, and second fusion polypeptide. This merging approach ensures correct assembly of the antibody-multimer-fusion while managing transfection complexity through unified ratio control rather than separate optimization of each component.
Data Source
AI summary
Herein is reported a method for producing an antibody-multimer-fusion polypeptide comprising (a) an antibody heavy chain and an antibody light chain, and (b) a first fusion polypeptide comprising in N- to C-terminal direction a first part of a non-antibody multimeric polypeptide, an antibody heavy chain CH1 domain or an antibody light chain constant domain, an antibody hinge region, an antibody heavy chain CH2 domain and an antibody heavy chain CH3 domain, and a second fusion polypeptide comprising in N- to C-terminal direction the second part of the non-antibody multimeric polypeptide and an antibody light chain constant domain if the first polypeptide comprises an antibody heavy chain CH1 domain or an antibody heavy chain CH1 domain if the first polypeptide comprises an antibody light chain constant domain, wherein (i) the antibody heavy chain of (a) and the first fusion polypeptide of (b), (ii) the antibody heavy chain of (a) and the antibody light chain of (a), and (iii) the first fusion polypeptide of (b) and the second fusion polypeptide of (b) are each independently of each other covalently linked to each other by at least one disulfide bond, characterized in that the antibody-multimer-fusion is expressed by a recombinant mammalian cell obtained by transfecting a mammalian cell with the expression cassettes for the antibody heavy chain, the antibody light chain, the first fusion polypeptide and the second fusion polypeptide at a stoichiometric ratio of 1:1:2:1.