Alpha-Gal specific IgG immune response after implantation of bioprostheses.
Thorac Cardiovasc Surg
; 57(4): 191-5, 2009 Jun.
Article
en En
| MEDLINE
| ID: mdl-19670109
ABSTRACT
BACKGROUND:
We have previously shown that the alpha-Gal (Galalpha1.3-Galbeta1-4GlcNAc-R) epitope is a relevant xenoantigen present on bioprostheses utilized in cardiac surgery and elicits an alpha-Gal specific IgM immune response. We sought to investigate whether that immune response continues after valve implantation. MATERIALS ANDMETHODS:
We collected plasma samples from patients who underwent bioprosthesis implantation (n = 19) or mechanical valve replacement (n = 8), respectively, prior to, at 10 days and at 3 months after cardiac surgery. ELISA was utilized to quantify alpha-Gal specific IgG and IgG subclasses. 3 bioprosthetic tissue samples were obtained from patients who had to undergo re-operation within 1 week (n = 1) or at 12-15 months (n = 2) after the initial operation. We utilized confocal laser scanning microscopy (CLSM) to detect the presence of alpha-Gal epitopes (IB4) and cell nuclei (DAPI).RESULTS:
alpha-Gal specific IgG was significantly increased 3 months after implantation of bioprostheses compared to preoperative values (p < 0.001) and was significantly higher than alpha-Gal specific IgG levels of the control group (p < 0.05). IgG3 was the major subclass directed against alpha-Gal (p < 0.05, pre- vs. postoperative values). In CLSM analysis we demonstrated that bioprostheses explanted 1 week after implantation contained IB4/DAPI positive cells within the collagen matrix. In contrast, in patients who underwent reoperation after 12 months, porcine tissue showed a complete lack of IB4/DAPI.CONCLUSION:
Our results indicate that the implantation of bioprostheses elicits a specific humoral immune response against alpha-Gal bearing cells compared to controls within 3 months after cardiac surgery. The complete absence of IB4/DAPI positive structures 12 months after implantation indicates a specific degradation of alpha-Gal bearing cells through previous exposure to the human blood circuit.
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Bioprótesis
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Inmunoglobulina G
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Prótesis Valvulares Cardíacas
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Alfa-Galactosidasa
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Válvulas Cardíacas
Límite:
Aged
/
Animals
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Humans
/
Middle aged
Idioma:
En
Revista:
Thorac Cardiovasc Surg
Año:
2009
Tipo del documento:
Article
País de afiliación:
Austria