Abstract

BACKGROUND: We attempted to develop a digital image analysis (DIA) systemfor endomyocardial biopsies (EMBs) to reliably quantify a) biopsy quality, b) immunohistochemically-markedinfiltrates, and c) cell adhesion molecules (CAMs) in relation to net heart area (HA) for the semi-automateddiagnosis of inflammatory cardiomyopathy (InfCM). MATERIAL/METHODS: 140 EMBs from dilated cardiomyopathy(DCM) patients and 14 autopsy heart samples (controls) were immunostained for T-lymphocytes (CD2, CD3,CD4, CD8), beta(2)-integrin+ infiltrates (CD18, LFA-1, Mac-1) and CAMs (immunoglobulin superfamily: ICAM-1,HLA class I, HLA DR, VCAM-1, CD58; selectins: CD62E and CD62P; and the beta(1)-integrin chain CD29).EMB quality was assessed visually on a three-point scale. Infiltrates were quantified visually (per hpf)and by DIA (per mm2 HA). CAM expression was evaluated semiquantitatively and by DIA (area fraction [AF]:stained area relative to HA). RESULTS: DIA-evaluated HA correlated significantly with the visual assessmentof EMB quality. The visual evaluation of both infiltrates and CAMs correlated significantly with therespective DIA-based quantification. DIA-quantified CAM-AF and infiltrates were discriminated by theCAM classification (CAMs+: n=87; 62%) compared to controls. DIA-quantified CAM immunoreactivity correlatedsignificantly with the DIA-quantified counter-receptor+ infiltrates. DIA evaluation of biopsy quality,infiltrates, and CAMs was devoid of inter- and intraobserver variability. CONCLUSIONS: The DIA systempresented here enables standardized and observer-independent assessment of EMB quality and intramyocardialinflammation (density of infiltrates and CAM expression) in DCM biopsies related to HA. Our data confirmthat endothelial CAM count and counter-receptor+ immunocompetent infiltration are interdependent pathogenicand diagnostic hallmarks of InfCM.

Keywords: Antigens, CD3, Biopsy, Cardiomyopathies, Cell Adhesion, Image Processing, Computer-Assisted, Myocardium, Phenotype, Research Support, Non-U.S. Gov