Characterization of CD57+PD1- CD4 T cells

We have identified a CD57+PD1- CD4 T cell phenotype at the time of transplantation that strongly correlates with subsequesnt development of belatacept-resistant rejection. In this study, we used microarray to determine which genes were upregulated in CD57+ compared to CD57- CD4 T cells. Peripheral blood obtained from 5 healthy controls was processed and sorted into CD4+CD57+PD1- and CD4+CD57-PD1- populations. Total RNA was extracted from the sorted populations and quality assessed. cDNA synthesis and amplification was performed, and fragmented and biotinylated samples were hybridized to the Affymetrix Human U133 plus 2.0 probe array. The arrays were scanned and probe intensity measurements were normalized across the samples using the robust multichip average (RMA) algorithm.