A recurring challenge in studying the human immune system is correlating in vitro results to in vivo responses, including modeling the complex and variable pathways of immune activation. This application note describes a protocol demonstrating the feasibility of using RBM’s TruCulture whole blood collection and culture system in conjunction with NanoString’s nCounter gene expression analysis platform.

RBM’s TruCulture is an in vitro system for characterizing the in vivo stimulation and response of circulating immune cells. These immune phenotyping studies are important for basic research as a tool to characterize immune regulation and dysregulation, as well as for pharmacodynamics studies in drug development to understand drug dosing, safety, and efficacy.

TruCulture can be used to investigate immune cell activation under a wide variety of stimuli and the closed system does not require extensive sample manipulation, specialized equipment or technical expertise; the procedure can be performed at the site of sample collection. Because it retains the cell pellet and culture supernatant, the TruCulture system enables both gene expression profiling and analysis of secreted proteins.

NanoString’s nCounter technology enables gene expression profiling using direct counting of individual RNA transcripts without enzymatic reactions. RNA is hybridized to oligonucleotides labeled with optical barcodes to enable direct, next-day quantification via digital counting of each barcode. The system can measure up to 800 transcripts over a six-fold log10 dynamic range with high accuracy and reproducibility because it does not rely on enzymatic reactions which can introduce bias. As a result, the nCounter platform is well suited for translational research where disease biomarkers discovered on the bench can be translated into a diagnostic assay in the clinic.