HLA antigens and cell adhesion molecules in the endomyocardial biopsy specimens patients with clinically suspected myocarditis.

The aim of this study was to characterise the expression of cell adhesion molecules (CAMs) and HLA antigens in biopsy specimens patients with two clinical suspected myocarditis. Study group consisted of 47 randomly selected patients (pts) classified in two groups based on left ventricular ejection fraction (LVEF): A - 29 pts, with LVEF £ 30% (24M, 5F, mean age 39±6) and B - 18 pts with LVEF >40% (15M, 3F, mean age 38±7). The expression of HLA class I (A,B,C) and II (DR) antigens and CAMs on frozen sections were examined using a Leica Bond Max autostainer (BOND Polymer Refine Red Detection; DS9390; Leica Biosystems) and monoclonal antihuman antibodies (HLA-DR, HLA-ABC, ICAM-1 and VCAM-1 from DAKO). The semiquantitative scoring system was defined as follows: 0-1, absent or slight focal staining of the endothelium; 2+, diffuse endothelial staining, 3+, diffuse endothelial and concomitant focal myocyte staining. The routine histopathological study was performed with hematoxylin & eosin and Masson trichrome stain. The data were analysed by a Mann-Whitney U test and Spearman R correlation coefficient test. A p value of <0.05 was statistically significant. The expression of HLA-DR antigens > 2+ was seen in the 17 (59%) pts in Gr. A and 12 (67%) in Gr. B. The expression of the HLA-A,B,C antigens was observed in the 11 (38%) and 12 (67%) pts, respectively. ICAM-1 and VCAM-1 immunoreactivity > 2+ was seen: ICAM-1, Gr. A - 12 (41%) and Gr. B - 9 (50%); VCAM-1, Gr. A - 6 (21%) and Gr. B - 9 (50%). There was no statistical differences between both groups and there was no relationship between LVEF and HLA-DR, HLAABC, ICAM-1 and VCAM-1 immunoreactivity. The lack relationship between positive staining for HLA antigens and CAMs in two groups of pts with clinically suspected myocarditis (with and without symptomatic congestive heart failure) indicates on independence of immunological reactions in myocardium. [ABSTRACT FROM AUTHOR]