P.R.I.S.M: Purification of exRNA by Immuno-capture and Sorting using Microfluidic - SUMMARY
Extracellular RNAs (exRNAs), protected from degradation in biofluids by a diverse set of carriers, are currently
considered as promising biomarkers. Indeed, it was shown that during disease progression, impacted
cells/tissues modify their registries of secreted exRNAs, carried by one or several protein or vesicular carriers,
which then participate in a modification of the global exRNAs profile in related biofluids. However, the clinically-
relevant exRNA modifications often represent a small fraction of the circulating exRNA within a given biofluid,
and could then remain undetectable when examining total biofluids exRNAs profiles. As such, establishing
efficient and specific exRNAs-carrier isolation methods, and downstream associated exRNAs reference profiles
in normal and disease situations, represents a prerequisite towards implementation of biofluid exRNAs profiling
as a routine diagnostic tool.
The objective of the P.R.I.S.M project (Purification of exRNA by Immuno-capture and Sorting using Microfluidics),
is to combine viscoleastic extracellular nanovesicle sorting with protein-affinity capture methods, using different
microfluidic chip device, in order to isolate distinct exRNA carriers (vesicles, lipoproteins, or RNA-binding
proteins) from a single sample of human biofluids (plasma, CSF, urine, milk), prior to RNA profiling. This project
will not only establish essential carrier-specific exRNA reference profiles for different human biofluids, but should
also dramatically improve the reproducibility, speed, sensitivity and specificity of exRNA-based diagnostic assays
compared to the current state-of-the-art in the field.
RELEVANCE
Circulating extracellular RNA (exRNAs) in biofluids, protected by distinct proteins and vesicular carriers, are
currently considered as promising biomarkers in diseases, such a cancer. However, only a small percentage of
the total exRNAs, clustered in some specific exRNA carriers, contain the clinically relevant information. Our
project aims at developing microfluidic methods for fractionating biofluid into its most relevant exRNAs carrier
components, from a single low volume of biofluid sample before characterizing their exRNA content. Upon
conclusion, we expect to reach a dramatic improvement in the specificity and sensitivity of exRNA diagnostic
strategies.