Protein detection problem under reducing condition

[Michael Schaefer]

> to the antibody. The Ab was used for immunoblot detection of target protein in cell
> lysates resolved by SDS-PAGE under reducing (no signal) or non-reducing (signal)
> conditions.

Did you immunize the animal with a peptide containing more than the terminal cysteine
which may be required for hooking it up to KLH?

If this is the case, some of the binding AB-species may recognize the oxidized form of
the cysteines. If your sample has a similar structure including disulfide bonds, these
more avidly binding antibodies may be predominant.

Michael