Nanowire-Mediated Delivery Enables Functional Interrogation of Primary Immune Cells: Application to the Analysis of Chronic Lymphocytic Leukemia

A circuit level understanding of immune cells and hematological
cancers has been severely impeded by a lack of techniques that enable
intracellular perturbation without significantly altering cell viability
and function. Here, we demonstrate that vertical silicon nanowires
(NWs) enable gene-specific manipulation of diverse murine and human
immune cells with negligible toxicity. To illustrate the power of
the technique, we then apply NW-mediated gene silencing to investigate
the role of the Wnt signaling pathway in chronic lymphocytic leukemia
(CLL). Remarkably, CLL-B cells from different patients exhibit tremendous
heterogeneity in their response to the knockdown of a single gene, LEF1. This functional heterogeneity defines three distinct
patient groups not discernible by conventional CLL cytogenetic markers
and provides a prognostic indicator for patients’ time to first
therapy. Analyses of gene expression signatures associated with these
functional patient subgroups reveal unique insights into the underlying
molecular basis for disease heterogeneity. Overall, our findings suggest
a functional classification that can potentially guide the selection
of patient-specific therapies in CLL and highlight the opportunities
for nanotechnology to drive biological inquiry.