We need to do everything fast in our lab which includes antibody purification process. I am reading about a new platform called:AKTAxpress that automatically purifies large numbers of monoclonal antibodies in pre-clinical screening. The system can purify up to 8 samples per run with a yield up to 50mg per sample. Before I call GE and ask, does anybody know if this systems purifies CHO cell proteins as well?

Sandy - absolutely. We have multiple AKTA units (e.g. Explorer, Purifier, and just plain old FPLC) and they can generally be used as a platform for any sort of liquid chromatography. The source of the protein (bacterial, mammalian cell expression, etc.) should not matter. I'm not all that familiar with the xpress system but I doubt it will be different in this regard. -PW

You can just use the Acta FPLC system - AS cut followed by gel filtration gives very clean Ab preps from SFM grown cells, so if you have lots of secreted prtns in (preferably) a serum low or serum free medium, you should have no trouble.

samm - any reason not to just use protein A? Do you get cleaner results from your AS/SEC method or is it a cost issue?

All mAbs (for whatever reason) do not bind well to prtnA or even prtn G - many hamster derived Abs are a case in point. For regular rabbit Abs, a prtn A mini-column is hard to beat. For a generalized protocol, irrespective of species or subtype, the AS cut of SFM/low serum medium (I use 44%, but the range is 40-50%) followed by gel filtration works great.
The gel filtration is not as good if you are using full serum media - given the size and salting% difference between albumin and IgG, I don't know why it shouuld be so, but thats my experience.

Makes sense, especially with respect to the hamster mAbs. IgA's would be similar, I suppose. For murine IgG1s, which tend to come up with us a lot, we can get by running protein A in high-salt conditions - we've generally found protein G to be less than optimal for prep scale work (I can't recall what the issues were exactly).

Thanks for the details and I'll have to try your method the next time this comes up.