Antibody crossreactivity - (Mar/30/2007 )
I isolate whole cell and supernatants from my bacterial cultures in order to investigate patterns of various protein expression in our secretion system. With one of our antibodies, when doing Western blot it cross-reacts with a major metalloprotease, so however the SDS gel looks, the same pattern is obtained on Western blots. Yhe same is not valid for whoel cells, no problem there. Any ideas? The antibody was against a component of the system that is either a regulator or is secreted itself.
overloading of gel or too much 1st Ab or 2nd Ab or bad (= unspecific) 1st Ab; test specificity with a control antigenic peptide or protein