The Annals of Thoracic Surgery, Vol 51, 30-33, Copyright © 1991 by The Society of Thoracic Surgeons
Binding of preformed xenoantibodies to porcine bioprosthetic valves
JA Sanchez, CC Marboe, JS Auteri, V Jeevanandum, NM Edwards, CL Berger and EA Rose
Department of Surgery, Columbia-Presbyterian Medical Center, New York, New York 10032.
We have investigated whether preformed antibodies against xenoantigens bind
to cellular elements remaining on porcine bioprosthetic valves after
various methods of preservation. Fresh porcine valves treated with either
acetone, 4% formaldehyde, or 0.625% glutaraldehyde, as well as an unfixed
valve, were incubated with antiserum against porcine xenoantigens. This
serum was prepared using the affinity purification method with porcine
lymphocytes as the target. The valves were stained with secondary
fluorescein-conjugated antibody against immunoglobulin M or immunoglobulin
G and examined under fluorescent microscopy. Intense binding of
immunoglobulin M to the endocardium was observed in the unfixed valve as
well as in valves fixed in acetone and formaldehyde. Glutaraldehyde
fixation eliminated binding of antibody. Binding was not noted within the
connective tissue. No binding of antiimmunoglobulin G was noted on the
endocardium of any of the sections. Examination of three
glutaraldehyde-treated porcine valves explanted from the aortic position
after 10 years in situ showed no immunoglobulin deposition. These results
demonstrate the elimination of antigenicity to preformed antibodies in the
endocardium and connective tissue of glutaraldehyde- preserved porcine
valves. The findings may, in part, explain the poor performance of
formaldehyde-preserved bioprosthetic xenograft valves in the past and
support the use of glutaraldehyde as a preferred agent for preservation of
bioprosthetic endovascular materials.
