CD81 and multiple system atrophy: Furthermore, since Aβ (AD) and α-syn (PD and MSA) biomarkers are located on the outer surface of sEVs, a minor modification to the Picciolini et al. [91] sensor, such as utilizing anti-Aβ or anti-α-syn instead of anti-CD81 might lead to the use of this sensor as a promising diagnostic assay for AD, PD, and MSA.