Pathogen burden in degenerative aortic valves is associated with inflammatory and immune reactions.
OBJECTIVE
The presence of five pathogens was assessed, together with a possible correlation of the total pathogen burden on inflammation and (auto)immunity in aortic stenosis (AS) and degenerative aortic valve bioprosthesis (BP).


METHODS
Diseased valve specimens from a total of 68 patients (52 with AS, 16 with BP) were studied. The presence and localization was assessed of Chlamydia pneumoniae (cHSP60), Helicobacter pylori (HP), cytomegalovirus (CMV), Epstein-Barr virus (EBV) and herpes simplex virus (HSV), as well as of macrophages (CD68), C-reactive protein (CRP) and human heat shock protein 60 (hHSP60), by using immunohistochemical and morphometric analyses.


RESULTS
In the majority of degenerative aortic valves, specific pathogens, inflammation and immunity were localized predominantly in the fibrosa of AS patients, and in superficial regions of the BP. The categorization of valves as having four or more pathogens (n = 37) or fewer pathogens (n = 31) demonstrated an increased signaling of CD68 (p = 0.03) and CRP (p = 0.02). Specifically, cHSP60, HP and hHSP60 levels were increased in valves where one or two bacteria were identified (n = 59) compared to those without bacterial presence (n = 9) (p = 0.04).


CONCLUSIONS
The pathogen burden may contribute to valvular degeneration by promoting further deleterious inflammatory and (auto)immune processes at the level of the valvular fibrosa.
Skowasch
Dirk
D
Department of Internal Medicine II - Cardiology, University of Bonn, Bonn, Germany. Dirk.Skowasch@ukb.uni-bonn.de
Tuleta
Izabela
I
Steinmetz
Martin
M
Pabst
Stefan
S
Preusse
Claus J
CJ
Welz
Armin
A
Nickenig
Georg
G
Bauriedel
Gerhard
G
D000368:Aged; D015703:Antigens, CD / Q000378:metabolism; D015214:Antigens, Differentiation, Myelomonocytic / Q000378:metabolism; D001021:Aortic Valve / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology*; D001024:Aortic Valve Stenosis / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology*; D001705:Bioprosthesis / Q000382:microbiology*; D002097:C-Reactive Protein / Q000378:metabolism; D018834:Chaperonin 60 / Q000378:metabolism; D005260:Female; D006350:Heart Valve Prosthesis / Q000382:microbiology*; D006801:Humans; D007150:Immunohistochemistry; D008264:Macrophages / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D000097382:CD68 Molecule
D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D002097:C-Reactive Protein; D018834:Chaperonin 60; C067980:CD68 antigen, human; D000097382:CD68 Molecule