No significant early activation of the cellular immune response after implantation of decellularized fresh pulmonary homografts

The longevity of homografts for heart valve replacement is determined by the amount of activation of the recipients' immune system caused by antigen reaction against the donated heart valve. Fresh decellularized pulmonary homografts have shown promising early results in pulmonary valve replacement and could potentially avoid significant activation of the immune system, as more than 99% of the donor DNA is removed during the decellularization process.

For this reason a team from Hannover Medical School between May 2009 and September 2013, analyzed 199 blood samples taken from 47 patients with a mean age at implantation of 16.6±10.8 years. Absolute counts and percentages of all cell type subsets, e.g. T-cells, B-cells and natural killer- cells, were determined by modern cell counting techniques (FACS).

Continued assessment up to 3 years after implantation did not show any significant deviations in cell counts from their individual baseline values. The authors concluded that the absence of cellular immune response in patients receiving decellularized homografts supports the concept that decellularization can provide a basis for autologous regeneration.

The results of the study have been recently published Open Access in TISSUE ENGINEERING: Part A.

Neumann A, Sarikouch S, Breymann T, Cebotari S, Boethig D, Horke A, Beerbaum P, Westhoff-Bleck M, Bertram H, Ono M, Tudorache I, Haverich A, Beutel G. Early systemic cellular immune response in children and young adults receiving decellularized fresh allografts for pulmonary valve replacement. Tissue Eng Part A. 2014 Mar;20(5-6):1003-11.