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My antigen precipitates or aggregates - (Dec/22/2010 )

Dear all,

I am working with an antigen that tends to aggregate and precipitate in PBS or PBS-like buffers.
I realized I can improve its solubility if I add some detergent like Tween 20 (0.05% final concentration).
Do you think this can be detrimental for the mice I use for immunization or for the efficiency of the immunization itself? If so, is there any way to bypass this hurdle?
Thank you in advance and Happy New Year!


I think you could have problems immunizing mice with an insoluble antigen. We tried it once, because our KLH-conjugate was not soluble, but we got a pretty sh*ty response. This insolubility in PBS is in my experience because the pI of your antigen is close to the pH of PBS. If your antigen is stable in lower or higher pH, you could try a buffer with a different pH. We have been able to avoid precipitation of one of our mAbs, that was notoriously difficult to keep in PBS, when we lowered the pH of the PBS to about 5.5.