Cellularity and content of unknown minor histocompatibility antigens in saphenous vein ECM scaffolds. (A) Both AR and SDS-decellularization processing methods were successful at decellularizing SV scaffolds determined by the lack of visible nuclei. Scale bar 200 μm. (B) Similarly, both processing methods resulted in scaffolds with significantly low levels of DNA content compared to untreated SV. (C) Via western blot, AR (Lane-2) was capable of significantly reducing both hydrophilic (D) and lipophilic (E) unknown minor histocompatibility antigens when compared to untreated SV (Lane–1). SDS (Lane–3) decellularization also reduced both hydrophilic and lipophilic antigens, however only lipophilic reduction was statistically different from untreated SV. Lack of statistical significance of hydrophilic antigen reduction for SDS scaffolds may be related to the nature of the non-parametric statistical tests utilized (Wilcoxon/Kruskal-Wallis Test with Dunn post-hoc analysis on non-parametric medians). * = p <0.05, ** = p < 0.01, *** = p < 0.001.