Expression of chimeric antibody in mammalian cells using dicistronic expression vector.

Area of Science:

• Biotechnology
• Molecular Biology
• Cell Biology

Background:

• Traditional expression systems for recombinant proteins in CHO cells often involve separate transcription units.
• Achieving high-level, stable expression of complex proteins like chimeric antibodies remains a challenge.

Purpose of the Study:

• To develop a dicistronic expression vector for enhanced production of recombinant chimeric antibodies in CHO cells.
• To investigate the efficiency of a novel splicing strategy for co-expression of a selectable marker and antibody cDNA.

Main Methods:

• Construction of a dicistronic expression vector integrating DHFR and recombinant antibody cDNA.
• Utilizing differential splicing for co-expression from a single transcript.
• Selection of stable CHO cell clones using methotrexate-containing medium.

Main Results:

• The dicistronic vector enabled stable CHO cell clones secreting nearly double the amount of chimeric antibodies.
• Efficient generation of high-expressing clones was achieved through stepwise methotrexate selection.
• The system demonstrated a convenient, high-level, and rapid expression of chimeric antibodies.

Conclusions:

• The developed dicistronic expression system offers a significant improvement for chimeric antibody production in CHO cells.
• The incomplete splicing DHFR gene strategy provides an efficient method for generating high-producing cell lines.
• This approach facilitates rapid and scalable manufacturing of therapeutic antibodies.