Ricerc@Sapienza

Bicuspid valve disease is associated with the development of thoracic aortic aneurysm. The molecular mechanisms underlying
this association still need to be clarified. Here, we evaluated the circulating levels of T and B lymphocyte subsets associated with
the development of vascular diseases in patients with bicuspid aortic valve or tricuspid aortic valve with and without thoracic
aortic aneurysm. We unveiled that the circulating levels of the MAIT, CD4+IL−17A+, and NKT T cell subsets were significantly
reduced in bicuspid valve disease cases, when compared to tricuspid aortic valve cases in either the presence or the absence of
thoracic aortic aneurysm. Among patients with tricuspid aortic valve, these cells were higher in those also affected by thoracic
aortic aneurysm. Similar data were obtained by examining CD19+ B cells, naïve B cells (IgD+CD27−), memory unswitched B
cells (IgD+CD27+), memory switched B cells (IgD−CD27+), and double-negative B cells (DN) (IgD−CD27−). These cells
resulted to be lower in subjects with bicuspid valve disease with respect to patients with tricuspid aortic valve. In whole,
our data indicate that patients with bicuspid valve disease show a quantitative reduction of T and B lymphocyte cell
subsets. Future studies are encouraged to understand the molecular mechanisms underlying this observation and its
pathophysiological significance.
1. Introduction