Cells of primarily extra-valvular origin in degenerative aortic valves and bioprostheses.
OBJECTIVE
We assessed aortic valves from patients with non-rheumatic aortic valve stenosis (AS) and with degenerative aortic valve bioprostheses (BP) for the presence of progenitor cell and leukocyte subtype-specific markers.


RESULTS
Diseased valve probes from a total of 87 patients (60 AS and 27 BP) were studied. We assessed presence and localization of endothelial progenitor cells (EPCs: CD34, CD133), dendritic cells (DCs: S100), T-lymphocytes (CD3), and macrophages (CD68) by immunohistochemical and morphometric analyses. In the majority of valves, we detected cell-bound signals of CD34 (48% of AS, 74% of BP, respectively), CD133 (58%/81%), S100 (58%/93%), CD3 (62%/81%), and CD68 (78%/93%). Labelled cells were predominantly localized within the valvular fibrosa. As key results, frequency of EPCs, DCs, macrophages, and lymphocytes was found significantly higher in BP when compared with AS (CD34: 19.2+/-23.2 vs. 5.7+/-13.0%; CD133: 13.7+/-12.4 vs. 5.5+/-8.3%; S100: 15.2+/-12.2 vs. 5.7+/-8.9%; CD3: 3.3+/-2.7 vs. 1.1+/-1.4%; CD68: 35.3+/-26.6 vs. 3.4+/-4.1%; each P<or=0.001).


CONCLUSIONS
EPCs and DCs were detected in a large collective of degenerative aortic valves, more frequently in bioprostheses than in native cusps. Aortoluminal presence of these primarily extra-valvular cells co-localized with inflammatory cells is a novel key feature involved in aortic valve degeneration.
Skowasch
Dirk
D
Department of Cardiology, Heart Center University of Bonn, Bonn, Germany. dirk.skowasch@ukb.uni-bonn.de
Schrempf
Stephanie
S
Wernert
Nicolas
N
Steinmetz
Martin
M
Jabs
Alexander
A
Tuleta
Izabela
I
Welsch
Ulrich
U
Preusse
Claus J
CJ
Likungu
James A
JA
Welz
Armin
A
Lüderitz
Berndt
B
Bauriedel
Gerhard
G
D000368:Aged; D001021:Aortic Valve / Q000473:pathology*; D001024:Aortic Valve Stenosis / Q000473:pathology* / Q000601:surgery; D001705:Bioprosthesis; D003713:Dendritic Cells / Q000473:pathology; D042783:Endothelial Cells / Q000473:pathology; D004730:Endothelium, Vascular / Q000473:pathology; D005260:Female; D006350:Heart Valve Prosthesis; D006801:Humans; D007150:Immunohistochemistry; D016131:Lymphocyte Subsets; D008264:Macrophages / Q000473:pathology; D008297:Male; D012189:Retrospective Studies; D013234:Stem Cells / Q000473:pathology*; D013601:T-Lymphocytes