Gene expression analysis for CD56- T, NK, CD56+ T cells, and iNKT cells

A small subset of T cells also expresses kiler-cell immunoglobulin-like receptors (KIRs). We find that KIR+ T cells primarily reside in the CD56+ T population. However, little is known on how these cells are different from the conventional CD56- T, NK, and iNKT cells. We used microarray profiling to compare and determine the distinctive differences of CD56+ T cell and its KIR subsets when compared to the conventional CD56- T, NK and iNKT cells. Lymphocyte subsets were sorted from human peripheral blood mononuclear cells with FACSAriaII (BD Biosciences, San Jose, CA) using anti-CD3, anti-CD56, anti-CD14, anti-KIR2DL1, anti-KIR2DL2/3, anti-KIR3DL1 and anti-TCRValpha24 antibodies. The purity of CD3+CD56- T cells, CD3-CD56+ NK cells, CD3+CD56+ T cells, KIR-CD3+CD56+ T cells, and KIR+CD3+CD56+ T cells were more than 98% in all experiments. The purities of iNKT cells for TCRValpha24 and CD1d-tetramer were >95% and >90%, respectively. RNA pre-amplification, labeling and hybridization on Human Genome U133Plus 2.0 GeneChip array were performed in the St. Jude Hartwell Center for Bioinformatics & Biotechnology microarray core facility according to the manufacturer’s instructions (Affymetrix, Santa Clara, CA).