Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
Cardiovasc Pathol. 2013 Jul-Aug;22(4):251-6. doi: 10.1016/j.carpath.2012.10.007. Epub 2013 Jan 4.
Outcomes in cases of adult accidental ABO incompatible cardiac transplantation are highly variable, with some patients suffering nearly immediate catastrophic antibody-mediated rejection while others (~37%-45%) survive. We hypothesize that these disparate outcomes could be influenced by variations in blood group antigen expression on allograft endothelium.
Immunohistochemical stains for blood Group A antigen were performed on cardiac tissue from 18 blood Type A cadavers. Staining was evaluated by two distinct modalities: semiquantitative light microscopy, which measured the intensity of antigen expression on endothelium, and quantitative digital analysis, which determined the percentage of the total tissue section area staining positive for blood Group A antigen. These data were used to compute a Comprehensive Expression Index (CEI) of blood Group A antigen expression for each specimen.
Semiquantitative light microscopic examination determined that endothelium was stained with low intensity in four (22%) myocardial samples, intermediate intensity in five (28%) samples, and high intensity in nine (50%) samples. Quantitative digital analysis revealed a range in the percentage of total cross sectional area composed of blood Group A-positive signal (median, 2.69%; interquartile range, 1.68%-2.94%). Increased percentage of total cross sectional area composed of blood Group A-positive signal was positively associated with patient age (P=.0037). The CEI showed a broad range, with a median of 5.27 and an interquartile range of 2.92-8.22.
There are little data available regarding interindividual differences in blood Group A antigen expression in cardiac endothelium. Here, we report interindividual variation in endothelial expression of blood Group A antigen in 18 specimens. These variations may help to explain disparate outcomes in cases of accidental ABO incompatible cardiac transplantation in adults.
成人意外 ABO 血型不相容心脏移植的结果差异很大，一些患者几乎立即发生灾难性的抗体介导排斥反应，而另一些患者（约 37%-45%）则存活下来。我们假设这些不同的结果可能受到同种异体移植内皮细胞血型抗原表达的变化影响。
对 18 例血型为 A 的尸体心脏组织进行了 A 血型抗原的免疫组织化学染色。染色通过两种不同的方式进行评估：半定量光镜，测量内皮细胞上抗原表达的强度；定量数字分析，确定总组织切片面积中 A 血型抗原阳性染色的百分比。这些数据用于计算每个标本的 A 血型抗原表达综合表达指数（CEI）。
半定量光镜检查确定，在 4 份（22%）心肌样本中，内皮细胞呈低强度染色，5 份（28%）样本呈中强度染色，9 份（50%）样本呈高强度染色。定量数字分析显示，总横截面积中 A 血型阳性信号的百分比范围（中位数，2.69%；四分位间距，1.68%-2.94%）。总横截面积中 A 血型阳性信号的百分比与患者年龄呈正相关（P=.0037）。CEI 显示出广泛的范围，中位数为 5.27，四分位间距为 2.92-8.22。
关于心脏内皮细胞中 A 血型抗原表达的个体间差异，数据很少。在这里，我们报告了 18 个标本中内皮细胞 A 血型抗原表达的个体间差异。这些变化可能有助于解释成人意外 ABO 血型不相容心脏移植中不同结果的原因。
