Nanoscale Extracellular Vesicle Analysis in Alzheimer’s Disease Diagnosis and Therapy

Figure 2

ExoScreen nsEV quantification assay schematic. Upon excitation at 680 nm the phthalocyanine-loaded donor bead converts endogenous diatomic oxygen to singlet oxygen. When donor beads are adequately proximal (~200 nm) to thioxene-loaded acceptor beads donor bead singlet oxygen causes emission of a 615 nm photon from the acceptor beads and produces a luminescent signal detected by the ExoScreen plate reader. For quantification of nsEVs derived from a particular tissue type donor bead exteriors are covalently coupled with anti-CD9 (nsEV surface marker protein) Abs and anti-cell type surface marker protein Abs are coupled to acceptor beads. ExoScreen assays can be carried out in 384-well plates and thus enable parallel quantification of nsEVs derived from multiple cell types in multiple plasma samples. Figure adapted from Yoshioka et al. [19] to illustrate use of ExoScreen nsEV assay for quantification of tissue-specific, for example, neuronal, nsEVs.