Expression Vector Segmentation for Immunoglobulin Yield
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current expression systems for immunoglobulins, particularly IgA and IgM, face challenges in achieving high yields due to the high molecular weight of IgM, which leads to endoplasmic reticulum stress and reduced secretion efficiency, resulting in low yields and cellular stress.
Innovation Solution
An expression vector is designed with separate cassettes for immunoglobulin heavy, light, and J chains, utilizing transcriptional regulatory elements with varying initiation capabilities to modulate expression ratios, ensuring higher expression levels of heavy and light chains compared to the J chain, thereby enhancing overall immunoglobulin production.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional expression systems are used for IgM, then the high molecular weight of IgM causes endoplasmic reticulum stress and reduced secretion efficiency, but this results in low yields and cellular stress
Solution Approach 1:
The expression system is segmented into separate expression cassettes for heavy chain, light chain, and J chain, allowing independent control of each component's expression. This segmentation enables optimization of transcriptional regulatory elements for each chain, preventing imbalanced expression that causes ER stress while maximizing overall immunoglobulin yield.
Solution Approach 2:
Different transcriptional regulatory elements with varying initiation capabilities are applied to different expression cassettes. The heavy and light chain cassettes use elements with higher initiation capability compared to the J chain cassette, creating local quality differences in expression control that optimize the overall expression ratio and reduce cellular stress.
2Productivity
If the expression level of J chain is increased to improve immunoglobulin assembly, then assembly efficiency improves, but the overall expression ratio becomes unbalanced causing ER stress
Solution Approach 1:
The J chain expression cassette uses a transcriptional regulatory element with lower initiation capability compared to the heavy and light chain cassettes. This creates a controlled expression ratio where heavy and light chains are expressed at higher levels than the J chain, maintaining balance and preventing ER stress while ensuring sufficient J chain for immunoglobulin assembly.
Solution Approach 2:
The transcriptional regulatory elements are designed with different initiation capabilities to control the expression ratio of different chains. By adjusting the initiation capability parameter of each regulatory element, the system achieves optimal expression ratios that balance assembly efficiency with cellular health.
Data Source
AI summary
The present disclosure provides an expression vector, comprising: a first expression cassette having a first transcriptional regulatory element and an immunoglobulin heavy chain-coding region operatively linked to the first transcriptional regulatory element; a second expression cassette having a second transcriptional regulatory element and an immunoglobulin light chain-coding region operatively linked to the second transcriptional regulatory element; and a third expression cassette having a third transcriptional regulatory element and an immunoglobulin J chain-coding region operatively linked to the third transcriptional regulatory element. The present disclosure further relates to the host cell comprising the expression vector and the use thereof.