Detection of the M30 neoepitope as a new tool to quantify liver apoptosis: timing and patterns of positivity on frozen and paraffin-embedded sections.
One of the first stages of apoptosis is cytokeratin cleavage mediated by caspases, which is associated with the expression of a neoepitope, the cleavage site of cytokeratin 18, identifiable by the M30 monoclonal antibody. The aim of this study was to evaluate the timing of neoantigen expression and its modifications in the various morphologic stages of apoptosis on frozen and paraffin-embedded sections from liver biopsies of patients with chronic hepatitis or transplanted liver. The appearance of this neoepitope coincides with the gradual disappearance of cytokeratins, with the appearance of nuclear DNA fragmentation, and with the presence of Councilman bodies. The staining patterns on paraffin-embedded sections of liver specimens were similar to those found in frozen sections, with a reduced sensitivity. The M30 antibody is correlated with apoptosis, and its specificity for epithelial cells makes this method the first choice for routine evaluation of apoptosis in liver epithelial cells.
Department of Internal Medicine, Cardioangiology, Hepatology, University of Bologna, Italy.
Alberto
A
Grassi
Micaela
M
Susca
Silvia
S
Ferri
Elena
E
Gabusi
Antonia
A
D'Errico
Gabriele
G
Farina
Silvana
S
Maccariello
Daniela
D
Zauli
Francesco B
FB
Bianchi
Giorgio
G
Ballardini
D000911:Antibodies, Monoclonal; D015415:Biomarkers / Q000032:analysis; D002467:Cell Nucleus / Q000378:metabolism / Q000473:pathology; D003593:Cytoplasm / Q000378:metabolism / Q000473:pathology; D053938:DNA Fragmentation; D018604:Epitope Mapping; D019084:Fluorescent Antibody Technique, Indirect; D005629:Frozen Sections; D006521:Hepatitis, Chronic / Q000378:metabolism / Q000473:pathology; D022781:Hepatocytes / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D020287:In Situ Nick-End Labeling; D007633:Keratins / Q000276:immunology / Q000378:metabolism*; D008099:Liver / Q000378:metabolism* / Q000473:pathology*; D016031:Liver Transplantation; D016612:Paraffin Embedding
D000911:Antibodies, Monoclonal; D015415:Biomarkers; D007633:Keratins