Ig titers--are there standards?

Tim Spahlinger txs at po.cwru.edu
Thu Jul 20 13:17:23 EST 2000

A long time ago, I did serial dilution antigen/antibody assays - particularly
for rubella.  This is about the oldest technology available for measuring the
presence of an antibody or antigen, and is useful only for determining
"positive" or "negative" for the presence of a particular antibody/antigen, and
for determining a "significant change" (i.e., four-fold change) in antibody
titer over time.  To my knowledge, there are no "conversion charts" for this
type of assay.  It is very crude and gives only "relative" results.

Russ wrote:

>         In the process of studying Chlamydophila pneumoniae, I have found
> that of IgA, IgG, and IgM titres used by various researchers to determine
> the state of infection varies greatly. IgG titers ranging from 16 to 512
> have been used by various researchers.
>         My guess is that different tests have different standards.The
> researchers probably decide to use higher or lower thresholds depending on
> what they are trying to learn.
>         Are there any standards for interpreting Ig levels? Any tables to
> convert results obtained with test Y to the corresponding results in test Z?
> Thanks for your attention.
> Russ Farris

More information about the Immuno mailing list