Integrated Analysis of Exosomal Protein Biomarkers on Alternating Current Electrokinetic Chips Enables Rapid Detection of Pancreatic Cancer in Patient Blood

In this article, the authors used Biological Dynamic ACE technology to screen whole blood and plasma samples from pancreatic cancer patients for the presence of both the exosome-associated protein CD63 and glypican-1 (GPC-1).

 Lewis JM, Vyas AD, Qiu Y, Messer KS, White R, Heller MJ. ACS Nano. 2018 Mar 28. doi: 10.1021/acsnano.7b08199.


ABSTRACT

Pancreatic ductal adenocarcinoma (PDAC) typically has nonspecific symptoms and is often found too late to treat. Because diagnosis of PDAC involves complex, invasive, and expensive procedures, screening populations at increased risk will depend on developing rapid, sensitive, specific, and cost-effective tests. Exosomes, which are nanoscale vesicles shed into blood from tumors, have come into focus as valuable entities for noninvasive liquid biopsy diagnostics. However, rapid capture and analysis of exosomes with their protein and other biomarkers have proven difficult. Here, we present a simple method integrating capture and analysis of exosomes and other extracellular vesicles directly from whole blood, plasma, or serum onto an AC electrokinetic microarray chip. In this process, no pretreatment or dilution of sample is required, nor is it necessary to use capture antibodies or other affinity techniques. Subsequent on-chip immunofluorescence analysis permits specific identification and quantification of target biomarkers within as little as 30 min total time. In this initial validation study, the biomarkers glypican-1 and CD63 were found to reflect the presence of PDAC and thus were used to develop a bivariate model for detecting PDAC. Twenty PDAC patient samples could be distinguished from 11 healthy subjects with 99% sensitivity and 82% specificity. In a smaller group of colon cancer patient samples, elevated glypican-1 was observed for metastatic but not for nonmetastatic disease. The speed and simplicity of ACE exosome capture and on-chip biomarker detection, combined with the ability to use whole blood, will enable seamless "sample-to-answer" liquid biopsy screening and improve early stage cancer diagnostics.

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Dielectrophoretic recovery of DNA from plasma for the identification of chronic lymphocytic leukemia point mutations

In this article,  the authors demonstrate feasibility of detecting cancer mutations in eluted cell-free DNA that was isolated from the plasma of chronic lymphocytic leukemia (CLL) patients using Biological Dynamics platform.

Sareh Manouchehri, Stuart Ibsen, Jennifer Wright, Laura Rassenti, Emanuela M Ghia, George F Widhopf, Thomas J Kipp & Michael J Heller


ABSTRACT

Aim: Circulating cell free (ccf) DNA contains information about mutations affecting chronic lymphocytic leukemia (CLL). The complexity of isolating DNA from plasma inhibits the development of point-of-care diagnostics. Here, we introduce an electrokinetic method that enables rapid recovery of DNA from plasma. Materials & methods: ccf-DNA was isolated from 25 µl of CLL plasma using dielectrophoresis. The DNA was used for PCR amplification, sequencing and analysis. Results: The ccf-DNA collected from plasma of 5 CLL patients revealed identical mutations to those previously identified by extracting DNA from CLL cells from the same patients. Conclusion: Rapid dielectrophoresis isolation of ccf-DNA directly from plasma provides sufficient amounts of DNA to use for identification of point mutations in genes associated with CLL progression.

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Detecting cancer biomarkers in blood: challenges for new molecular diagnostic and point-of-care tests using cell-free nucleic acids

In this review, the authors discuss emerging cell-free nanoparticles isolation technologies that demonstrate the potential for being translated into for point-of-care application. The simplicity of sample preparation used in Biological Dynamics AC dielectrophoretic separation enables future applications of molecular diagnostics at point-of-care.

Lewis JM, Heineck DP, Heller MJ. Expert Rev Mol Diagn. 2015 Jul 18. doi: 10.1586/14737159.2015.1069709. 


Abstract

As we move into the era of individualized cancer treatment, the need for more sophisticated cancer diagnostics has emerged. Cell-free (cf) nucleic acids (cf-DNA, cf-RNA) and other cellular nanoparticulates are now considered important and selective biomarkers. There is great hope that blood-borne cf-nucleic acids can be used for ‘liquid biopsies’, replacing more invasive tissue biopsies to analyze cancer mutations and monitor therapy. Conventional techniques for cf-nucleic acid biomarker isolation from blood are generally time-consuming, complicated and expensive. They require relatively large blood samples, which must be processed to serum or plasma before isolation of biomarkers can proceed. Such cumbersome  sample preparation also limits the widespread use of powerful, downstream genomic analyses, including PCR and DNA sequencing. These limitations also preclude rapid, point-of-care diagnostic applications. Thus, new technologies that allow rapid isolation of biomarkers directly from blood will permit seamless sample-to-answer solutions that enable next-generation point-of-care molecular diagnostics.

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Rapid Electrokinetic Isolation of Cancer-Related Circulating Cell-Free DNA Directly from Blood

The authors used Biological Dynamics AC electrokinetic platform to isolate, to elute and to sequence cell-free DNA from 25 μL unprocessed blood from 15 chronic lymphocytic leukemia (CLL) patients and 3 healthy individuals. The complete process, blood to PCR, required <10 min.

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