Isolation of high quality protein samples from punches of formalin fixed and paraffin embedded tissue blocks
J. Kroll1, K.F. Becker2, S. Kuphal1, R. Hein3, F. Hofstädter1 and A.K. Bosserhoff1
1Institute of Pathology, University of Regensburg, Regensburg, Germany, 2Institute of Pathology, TU Munich, Germany and 3Department of Dermatology, TU Munich, Germany.
Offprint requests to: Anja K. Bosserhoff, Institute of Pathology, University of Regensburg, Franz-Josef-Strauss-Allee 11, D-93053 Regensburg, Germany. e-mail: anja.bosserhoff@klinik.uni-regensburg.de
Summary. In general, it is believed that the extraction of proteins from formalin-fixed paraffin embedded samples is not feasible. However, recently a new technique was developed, presenting the extraction of non-degraded, full length proteins from formalin fixed tissues, usable for western blotting and protein arrays. In the study presented here, we applied this technique to punch biopsies of formalin fixed tissues embedded in paraffin to reduce heterogeneity of the tissue represented in sections, and to ensure analysing mainly defined cellular material. Successful extraction was achieved even from very small samples (0.7 mm3). Additionally, we were able to detect highly glycosylated proteins and protein modification, such as phosphorylation. Interestingly, with this technique it is feasible to extract high quality proteins from 14 year old samples. In summary, the new technique makes a great pool of material now usable for molecular analysis with high throughput tools. Histol Histopathol 23, 391-395 (2008)
Key words: Formalin fixed tissues, Protein extraction, Western blotting, Protein modification
DOI: 10.14670/HH-23.391