title: Detection of apoptoses in gastro-intestinal graft-versus-host disease and cytomegalovirus colitis by a commercially available antibody against caspase-3.
abstract: The common pathway of any apoptotic cascade leads to the activation of the so-called execution caspases, particularly caspase-3 (CSP3). The question of whether immunohistochemical (IHC) detection of activated CSP3 might be useful for routine purposes still needs to be clarified. We analyzed apoptoses in gastrointestinal graft-versus-host disease (GvHD) and cytomegalovirus (CMV) colitis using a commercially available polyclonal antibody against activated human CSP3. In GvHD samples obtained from the colon, apoptoses detected by CSP3 varied between 11 and 43/40 crypts, and in esophageal specimens between 21 and 40/1.5 mm squamous epithelium basal length. This count was correlated with the apoptotic count assessed on hematoxylin- and eosin (H&E)-stained slides. A perfect concordance for those counting between 30 and 40 apoptoses/40 crypts or 1.5 mm squamous epithelium basal length was detected, whereas cases with low apoptotic counts on the H&E stained slides showed a 2 to 3 fold greater number of stained nuclei as assessed by CSP3 staining. In CMV-colitis, although the number of exploding crypt cells was 8-13/40 crypts, only 1-2 nuclei/40 crypts and almost all cells with typical nuclear inclusions stained positively. The presence of CMV can be easily detected on H&E- or IHC-stained slides, while masked GvHD by an overlying CMV-colitis might remain unrecognized. Staining for CSP3 may be helpful in distinguishing these two conditions, as apoptotic count would be excessive in GvHD.
authors.affiliation: Institute of Pathology, University of Innsbruck, Austria. alexandar.tzankov@uibk.ac.at
authors.forename: Alexandar
authors.initials: A
authors.lastname: Tzankov
authors.forename: Gerald
authors.initials: G
authors.lastname: Stifter
authors.forename: Ines
authors.initials: I
authors.lastname: Tschörner
authors.forename: Günther
authors.initials: G
authors.lastname: Gastl
authors.forename: Gregor
authors.initials: G
authors.lastname: Mikuz
mesh_terms: D017209:Apoptosis; D053148:Caspase 3; D020169:Caspases / Q000276:immunology*; D003092:Colitis / Q000473:pathology* / Q000821:virology; D003587:Cytomegalovirus; D003586:Cytomegalovirus Infections / Q000473:pathology*; D004789:Enzyme Activation; D005767:Gastrointestinal Diseases / Q000473:pathology; D006086:Graft vs Host Disease / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D012680:Sensitivity and Specificity
chemical_list: C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases