This is up to you. it’s your choice. The important question is how do you make an antibody? I have to say all of them have their historical and technological origins in a furry beasty, notable mice and rats.
You said “ I read that ocrelizumab was made from Chinese hamster ovary cells…. Is my ocrelizumab harvested inside a hamster?”
Fear not, this is not the product of the reproductive cycle of Hammy the Hamster.
Monoclonal antibodies, of which ocrelizumab is one example, mean that every antibody molecule is the same having come from one cell (mono (one)-clonal (clone). Ocrelizumab has its origins in a mouse. Furry beasties were probably injected with human CD20 protien and then their spleen B cells were fused with a mouse B cell cancer cell line such (For example NS-1, SP2/0 cells). This makes the B cell that produces the antibody to become immortal and so can be grown for ever.
Then, the bods from Genetech (Roche) engineered the parent mouse monoclonal antibody [termed 2H7-probably the second 96 cell well plate which is 12 (1-12) x 8 (A-H) so the positive well was on the last row of the 7th column] to be humanised and called it ocrelizumab[ocre(name)li(Immune target)zu(humanised)mab(monoclonal antibody)], so it is largely human and only has the antigen (CD20)-binding bits from the original mouse antibody and the rest is human protein. We could name this molecule ocreliomab [ocre(name)li (immune target)o(mouse) mab (monoclonl antibody)]. This humanised protein has to be grown and you need a cell to produce this. They could grow it from bacterial cells (as occurs with betaseron = beta interferon-1b), which does not add carbobohydrates to the proteins or one can make it in mammalian cells (as occurrs with avonex and rebif = beta interferon-1a). Chinese hamster ovary cells are used because they are good for protein production. Likewise HEK293 (human embryonic kidney cells) are used for cell expression studies as they are easy grow and add DNA to the cells.
They grew ocrelizumab in Chinese hamster ovary (CHO) cells. These are an epithelial cell line derived from the ovary of the Chinese hamster, often used in biological and medical research and commercially in the production of therapeutic proteins. They have found wide use in studies of genetics, toxicity screening, nutrition and gene expression, particularly to express recombinant proteins. CHO cells are the most commonly used mammalian hosts for industrial production of recombinant protein therapeutics.
They clone the DNA of ocrelizumab into the DNA of the CHO cells and grow it in big fermenting vats and the ocrelizumab gets secreted from the CHO cells. This is then purified and and bottled for human use. So whilst it is made in a hamster cell, no animal had to be used in the production of the antibody, as long as the cells are grown in serum-free-medium.
Hope that answers the question