>In article <JCARTER.9.000E1848 at FHCRC.ORG>, JCARTER at FHCRC.ORG (Jody)
>writes:
>>>We are having trouble measuring the amount of antigen specific human IgM
>>n an ELISA. We know that part of the problem is antigen specific IgG
>but
>>have not had success removing IgG with protein A (both the IgG and the
>IgM
>>reactions were reduced by about half). Any suggestions?
>>Most manufacturers of in vitro diagnostic kits use goat anti-human IgG to
>remove antigen-specific IgG before testing for antigen-specific IgM.
>Naturally you would have to titer out the goat anti-human IgG to be sure
>you are removing "all" of the antigen-specific IgG. Hope this helps.
Another strategy is to coat wells with anti-human
IgM to capture all of the human IgM, then add
viral lysate, then anti-viral antibody, then
conjugated antibody to that antibody. This seems
to work, and allegedly does away with rheumatoid
factor reactivity.
Brian
