Polymerase chain reaction for the detection of Helicobacter pylori in formaldehyde-sublimate fixed, paraffin-embedded gastric biopsies.
To improve morphologic detail and immunohistochemical staining, mercuric chloride-containing fixatives such as formaldehyde-sublimate (FS) has been widely used as an alternative for neutral buffered formalin. FS-fixed, paraffin-embedded tissue, however, is considered to be an unreliable source of DNA. We used an adapted DNA-extraction method for FS-fixed, paraffin-embedded tissue. In all cases tested we obtained amplifiable DNA with polymerase chain reaction (PCR), after FS-fixation and after fixation in neutral buffered formalin as well. A PCR assay for the 16S-rRNA region of Helicobacter pylori was developed amplifying a fragment of 145 bp. The specificity of this PCR assay was tested on a range of different microorganisms. PCR was performed on 46 archival FS-fixed paraffin-embedded gastric biopsies. The results were compared with histologic examination and with immunohistochemical detection using a polyclonal antibody against H. pylori. Both PCR and immunohistochemistry are very sensitive methods for the detection of H. pylori. A PCR offers the possibility of additional subtyping in archival FS-fixed, paraffin-embedded tissue.
Scholte
G H
GH
Department of Pathology, Slotervaart Hospital, Amsterdam, The Netherlands.
van Doorn
L J
LJ
Quint
W G
WG
Lindeman
J
J
D001706:Biopsy; D015139:Blotting, Southern; D017931:DNA Primers; D004269:DNA, Bacterial / Q000302:isolation & purification*; D005756:Gastritis / Q000382:microbiology* / Q000473:pathology*; D016481:Helicobacter Infections / Q000473:pathology*; D016480:Helicobacter pylori / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D007150:Immunohistochemistry; D016612:Paraffin Embedding; D016133:Polymerase Chain Reaction; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012680:Sensitivity and Specificity; D016707:Tissue Fixation
D017931:DNA Primers; D004269:DNA, Bacterial; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S