MicroRNAs (miRNAs) are endogenous, non-coding RNAs comprising approximately 21-23 nucleotides that regulate gene expression by binding to and targeting messenger RNA (mRNA) for translational repression or degradation. miRNAs have been shown to regulate cellular processes including proliferation, differentiation, and development and to play an important role in immune system function. The expression of miRNAs is misregulated in numerous diseases, including cancers of immunological origin. To better understand the role of miRNA in T-cell activation, we used a real-time PCR-based system to analyze changes in miRNA expression following activation of Jurkat T-cells with the inducing agents Phorbol Myristyl Acetate (PMA) and Ionomycin (CI) and detected several miRNAs that showed differential regulation following treatment. Using this system, miRNAs and their mRNA targets, along with other noncoding RNAs, can be simultaneously detected and quantified using SYBR (R) Green real time-PCR, enabling comprehensive, genome-wide expression profiles of multiple RNA species. (C) 2012 Elsevier Inc. All rights reserved.