Analysis of cell-specific peripheral blood biomarkers in severe allergic asthma identifies innate immune dysfunction

Asthma is a disease of complex origin and multiple pathologies. There are currently very few biomarkers of proven utility in its diagnosis, management or response to treatment. Recent studies have identified multiple asthma phenotypes following biofluid analysis; however, such findings may be driven by the well-characterised alterations in immune cell populations in asthma. We present a study designed to identify cell type-specific gene signatures of severe allergic asthma in peripheral blood samples. Using transcriptomic profiling of four magnetically purified peripheral blood cell types, we identify significant gene expression changes in monocytes and NK cells but not T lymphocytes in severe asthmatics. Pathway analysis indicates dysfunction of immune cell regulation and bacterial suppression in the NK cells. These gene expression changes may be useful on their own as prognostic peripheral blood cell markers of severe asthma, but also may indicate novel cell pathways for therapeutic intervention.