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Too many positive signals fromimmunological screening of a cDNA librar - (Aug/08/2001 )

We are screening a cDNA library expressed in E. coli using monoclonal antibody raised againsta novel apolipoprotein (p27) in turtle. We plate out the library, apply nitrocellulose filter and then immunostain the filter. All the plaques on the filter come up positive on a primary screen - seems avery unlikely result We don't think the problem is with the dilutions (all the positive signals areclear/well defined), but with the primary monoclonal (anti-p27), which was created in-house.Does anyone have any advice on this issue and where to go from here?

William BurnsVisiting Science Scholar at the University of Delaware, USA


Did you check your secondary for reactivity against E coli? You may have to absorb theE coli reactivity first.