Calcific aortic valve stenosis: Immunohistochemical analysis of inflammatory infiltrate

Calcific aortic valve disease is considered a form of atherosclerosis and, like the latter, possibly of inflammatory origin. The aim of our work was to study the pattern of cellular infiltrate in calcific aortic valve stenosis (CAS). Fifteen operatively excised calcified aortic valves were examined by histology and immunohistochemistry (CD20, CD79α, CD3, CD4, CD8, CD68, CD138, CD117, BJK, BJL, IgA, IgD, IgG, IgG4 and IgM). The findings revealed that in CAS, there were chronic inflammatory features with infiltrates comprising lymphocytes, polyclonal plasma cells, histiocytes and mast cells. In T-lymphocytes, CD4 prevailed over CD8. In B-lymphocytes, there was a slight preponderance of CD20 over CD79α. The BJL (lambda)-positive plasma cells prevailed over the BJK (kappa) ones. The CD138-positive plasma cells comprised 24% IgA-, 20% IgD-, 41% IgG- (including 11% of IgG4-) and 15% IgM-positive cells. CAS did not fulfill the criteria of the recently described clinicopathological entity IgG4-related sclerosing systemic disease. The inflammatory process was the same in both subsets of CAS - those with trileaflet (normally formed) valves and those with congenitally bicuspid valves.