IgM ELISA?

[bhjelle at unm.edu]

>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