Today’s research demands fast identification of potential diagnostic and therapeutic targets. We describe a novel phage display strategy to identify disease-related proteins that are specifically expressed in a certain (diseased) tissue or cell. Phages displaying antibody fragments are selected on complex protein mixtures in a two-step manner, combining subtractive selection in solution with further enrichment of specific phages on two-dimensional western blots. Targets recognized by the resulting recombinant antibodies are immunoaffinity purified and identified by mass spectrometry. We used antibody fragment libraries from autoimmune patients to discover apoptosis-specific and disease-related targets. One of the three identified targets is the U1-70K protein, a marker for SLE overlap disease. Interestingly, the epitope on U1-70K, recognized by the selected recombinant antibody, is shown to be apoptosis-dependent, and such epitopes are believed to be involved in breaking tolerance to self-antigens. The other two proteins are identified as PSF / p54^nrb and hnRNP C.