Construction of chimaeric processed immunoglobulin genes containing mouse variable and human constant region...

Area of Science:

• Immunology
• Molecular Biology
• Biotechnology

Background:

• Monoclonal antibodies offer specificity for diagnosing and treating human neoplasia.
• Mouse antibodies face neutralization due to immune reactions from repeated administration of heterologous antibodies.
• Chimeric immunoglobulins, combining mouse variable and human constant regions, can mitigate these immune responses.

Purpose of the Study:

• To construct a chimaeric immunoglobulin gene by combining mouse and human genetic elements.
• To demonstrate precise splicing of chimaeric intervening sequences within a recombinant retrovirus DNA construct.
• To establish a method for expressing chimaeric mouse-human immunoglobulin genes in various cell systems.

Main Methods:

• Construction of recombinant retrovirus DNA carrying specific heavy-chain (H) variable-diversity joining (VH-D-JH) and C gamma 1 genes.
• Utilizing genes from different species to create the chimaeric construct.
• Analysis of gene splicing to confirm precise removal of intervening sequences.

Main Results:

• Successful construction of a recombinant retrovirus DNA encoding chimaeric immunoglobulin genes.
• Precise splicing of chimaeric intervening sequences was confirmed.
• Demonstrated a method for expressing chimaeric mouse-human immunoglobulin genes in Escherichia coli, yeast, and animal cells.
• Observed unexpected use of a hidden splice donor site, leading to V region formation without a leader sequence.

Conclusions:

• The developed procedure effectively constructs chimaeric mouse-human immunoglobulin genes.
• This method facilitates the expression of these genes in diverse cellular systems for potential therapeutic applications.
• The unexpected splicing event highlights a novel aspect of V region gene formation.