Affordable Access

deepdyve-link
Publisher Website

Methods for restoration of ki67 antigenicity in aged paraffin tissue blocks.

Authors
  • Grillo, Federica1, 2
  • Campora, Michela3
  • Pigozzi, Simona3, 4
  • Bonadio, Silvia4
  • Valle, Luca3
  • Ferro, Jacopo3
  • Paudice, Michele3
  • Dose, Beatrice3
  • Mastracci, Luca3, 4
  • 1 Anatomic Pathology Unit, Department of Surgical Sciences and Integrated Diagnostics (DISC), University of Genova, IRCCS AOU San Martino IST, Largo Rosanna Benzi, 10, 16132, Genoa, Italy. [email protected] , (Italy)
  • 2 Anatomic Pathology, Ospedale Policlinico San Martino IRCCS, Genova, Italy. [email protected] , (Italy)
  • 3 Anatomic Pathology Unit, Department of Surgical Sciences and Integrated Diagnostics (DISC), University of Genova, IRCCS AOU San Martino IST, Largo Rosanna Benzi, 10, 16132, Genoa, Italy. , (Italy)
  • 4 Anatomic Pathology, Ospedale Policlinico San Martino IRCCS, Genova, Italy. , (Italy)
Type
Published Article
Journal
Histochemistry and cell biology
Publication Date
Aug 01, 2021
Volume
156
Issue
2
Pages
183–190
Identifiers
DOI: 10.1007/s00418-021-01987-w
PMID: 33837842
Source
Medline
Keywords
Language
English
License
Unknown

Abstract

Pathology archives are a treasure trove of paraffin embedded tissue spanning many years and covering a wide variety of tissues and diseases. The possibility of using old archival formalin fixed paraffin embedded (FFPE) tissues for diagnostic updates and research projects is a widespread need and it requires archives of stable, well-preserved samples. Immunohistochemistry performed on old archival paraffin blocks may give unreliable results, in particular for some antigens, such as Ki67. In consideration of this phenomenon, our aim is to comprehensively test and identify methods which may be used to obtain Ki67 immunohistochemical reactions of good quality from old archival FFPE blocks. Various methods were tested in order to evaluate their possible efficacy in increasing Ki67 immunointensity in a collection of 40-year-old, archival blocks including re-embedding, with deeper sectioning of tissue from the block and increasing heat-based pretreatment times (20 cases) and re-processing (20 cases). All reactions were performed using an automated immunostainer and Ki67 stained immunosections compared using a visual colour-based scale (the first immunostained section was considered as baseline). The combination of deep sectioning (1000 µM) and prolonged heat-based pretreatment (64 min) markedly increased immunoreactivity for Ki67. Re-embedding and reprocessing did not have a significant effect. Large tissue samples showed heterogeneity of Ki67 immunoexpression between the periphery of the sample and the central area. In conclusion, the study defines a useful protocol to increase antigen retrieval applicable to dated archival tissues. © 2021. The Author(s).

Report this publication

Statistics

Seen <100 times