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How is rituximab produced?

veganmua

Senior Member
Messages
145
Location
London, UK
I know it is an chimera of mouse/human antibodies, but are mice used in the production process, or is it a case of the cells that were originally harvested from mice being used indefinitely in vitro?
Basically what I'm asking is was the mouse involvement a one off thing, or are new mice needed to replenish the source constantly?
I'm hoping it's something similar to Henrietta Lack's HeLa cells?

I've been researching this online, but I seem to have reached a dead end.
 
Messages
2,087
I know it is an chimera of mouse/human antibodies, but are mice used in the production process, or is it a case of the cells that were originally harvested from mice being used indefinitely in vitro?
Basically what I'm asking is was the mouse involvement a one off thing, or are new mice needed to replenish the source constantly?
I'm hoping it's something similar to Henrietta Lack's HeLa cells?

I've been researching this online, but I seem to have reached a dead end.

I can't speak for rituximab specifically but I am familiar with the production methods of monoclonal antibodies and proteins from recombinant DNA ( specifically ones derived from chinese hamster ovary cells ) Most biological drugs are manufactured similarly.

The cells are modified genetically to produce the protein required. Basically then there is a master cell bank from which all batches get made. No further mice or chinese hamsters are involved in the process once a master cell bank is made.

A typical batch starts off in a flask and as the cells multiply it is transferred in to ever increasing sized vessels eventually ending up in a production bioreactor of up to 20,000 litre in some cases.This can take several weeks.

Then the cells need to be discarded and the protein needs to be harvested. Then the protein carrying solution is purified to remove impurities from the host cell. This involves a lot of filtration and chromatography steps. Finally the solution is exchanged with a buffer that is suitable for freezing or lyophilisation or final filling, for eventual injection or infusion.

If you want to know any specifics let me know. I don't know much of the biology or genetics bit I do know the manufacturing side of things.
 
Messages
2,087
Was biotechnology your area of work or study then?

Chemical Engineering was my degree but I ended up working in biotechnology.

Actually just remembered, I worked in novartis where they make the polio vaccine and that process does involve live monkeys. But that's a different method altogether and I wasn't involved with it specifically, just mentioning it cause it's the only bio process I am aware of that uses live animals. Although novartis also make the flu vaccine which uses chicken eggs....
 

veganmua

Senior Member
Messages
145
Location
London, UK
@BurnA Thanks so much for the info, you're a legend! I'm so glad to hear that it is a one off use rather than a continuous use of mice. Obviously in an ideal world there would be no use altogether, but that is not the world we live in. What did they make from the Chinese hamsters?
 
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2,087

alicec

Senior Member
Messages
1,572
Location
Australia
Basically what I'm asking is was the mouse involvement a one off thing, or are new mice needed to replenish the source constantly?

Mouse involvement is a one-off thing. The original antibody to CD20 (the target of rituximab) was produced in a mouse.

Fancy recombinant DNA techniques were then used to fuse the DNA coding for the specific recognition part of the mouse IgG with DNA coding for the backbone of human IgG, creating a chimeric mouse-human antibody.

This chimeric DNA construct was then inserted into Chinese hamster ovary cells which are able to produce the chimeric IgG protein with all appropriate modifications for proper function (bacterial cells, which are commonly used for production of recombinant proteins are not able to make all these modifications). The CHO cells can then be grown on a large scale, just like the HeLa cells.