Sarcoidosis-specific markers from whole blood gene expression

We hypothesized that microarray analyses of whole blood gene expression would identify patterns of gene expression useful in the diagnosis for sacroidosis and identify inflammatory mediators relevant to the underlying pathophysiology. We analyzed whole blood RNA from 37 patients with sarcoidosis, 20 healthy controls and 6 patients with hypersensitivity pneumonitis using genome-wide expression microarrays. We developed a classification algorithm using a derivation and validation subset approach, analyzed the most discriminative gene expression changes, and confirmed selected expression changes using flow-cytometry.