Plasma Biomarker for Post-concussive Syndrome: A Pilot Study Using an Alternating Current Electro-Kinetic Platform

Abstract

Background: Technology platforms that afford biomarker discovery in patients suffering from traumatic brain injury (TBI) remain an unmet medical need. Here, we describe an observational pilot study to explore the utility of an alternating current electrokinetic (ACE) microchip device in this context. Methods: Blood samples were collected from participating subjects with and without minor TBI. Plasma levels of glial fibrillary acidic protein (GFAP), Tau, ubiquitin C-terminal hydrolase L1 (UCH-L1), and cell-free DNA (cfDNA) were determined in subjects with and without minor TBI using ACE microchip device followed by on-chip immunofluorescent analysis. Post-concussive symptoms were assessed using the Rivermead Post Concussion Symptoms Questionnaire (RPCSQ) at one-month follow-up. Results: Highest levels of GFAP, UCH-L1, and Tau were seen in two minor TBI subjects with abnormality on head computed tomography (CT). In patients without abnormal head CT, Tau and GFAP levels discriminated between plasma from minor-TBI and non-TBI patients, with sensitivity and specificity of 64-72 and 50%, respectively. Plasma GFAP, UCH-L1, and Tau strongly correlated with the cumulative RPCSQ score. Plasma UCH-L1 and GFAP exhibited highest correlation to sensitivity to noise and light (r = 0.96 and 0.91, respectively, p < 0.001). Plasma UCH-L1 and Tau showed highest correlation with headache (r = 0.74 and 0.78, respectively, p < 0.001), sleep disturbance (r = 0.69 and 0.84, respectively, p < 0.001), and cognitive symptoms, including forgetfulness (r = 0.76 and 0.74, respectively, p < 0.001), poor concentration (r = 0.68 and 0.76, respectively, p < 0.001), and time required for information processing (r = 0.77 and 0.81, respectively, p < 0.001). cfDNA exhibited a strong correlation with depression (r = 0.79, p < 0.01) and dizziness (r = 0.69, p < 0.01). While cfDNA demonstrated positive correlation with dizziness and depression (r = 0.69 and 0.79, respectively, p < 0.001), no significant correlation was observed between cumulative RPCSQ and cfDNA (r = 0.07, p = 0.81). Conclusion: We provide proof-of-principle results supporting the utility of ACE microchip for plasma biomarker analysis in patients with minor TBI.

Simultaneous Isolation of Circulating Nucleic Acids and EV-Associated Protein Biomarkers From Unprocessed Plasma Using an AC Electrokinetics-Based Platform

“…The EVs captured from the MDA-MB-231 cell line were also examined with scanning electron microscopy (SEM) as shown in Figure 8. Vesicles with a spherical and/or peaked-spherical morphology, as previously noted (Ibsen et al, 2017;Lewis et al, 2020), were observed to decorate both the top and bottom of the electrode edges. The structures observed are in the range of 100-200 nm in concordance with the particle sizing measurements while the less-than perfect spherical form may be attributed to protein aggregation around the vesicles.…”

“…Following the capture, biomarkers of interest are characterized either on the chip using fluorescent detection or eluted off the chip for secondary analysis with technologies such as PCR and NGS. On-chip detection of cancer biomarkers using the ACE method, as well as in-situ and downstream analysis of the captured biomarkers, have been demonstrated by multiple research groups ( Sonnenberg et al, 2014 ; Manouchehri et al, 2016 ; Ibsen et al, 2017 ; Lewis et al, 2018 , 2019 , 2020 ). The objective of this work was to evaluate the feasibility of using a single-chip, multi-omic workflow from the perspective of applications in personalized medicine.…”

cyc‐DEP: Cyclic immunofluorescence profiling of particles collected using dielectrophoresis

“…To the best of our knowledge, the application of cyclic IF, a technique traditionally used for multiplex spatial proteomic profiling of tissues and cells, to liquid biopsies has not been previously reported. The use of this particular DEP chip technology for the rapid isolation of biomarkers, including exosomal proteins, from low-volumes of plasma has previously been demonstrated for up to two proteins per assay [48] in patients with glioblastoma [27], postconcussive syndrome [28], pancreatic and colon cancer [29], and chronic lymphocytic leukemia [30,31]. cyc-DEP increases the number of targets measured per 25 µl of fluid sample by a factor of at least 3, opening the door for detecting several biomarkers from small volumes of patient plasma and other liquid biopsy samples.…”

“…The DEP chip platform allows for the quantification of proteins associated with extracellular vesicles (EVs) or other endogenous nanoparticles (NPs) by IF imaging. Researchers have previously conducted on-chip IF imaging of up to two proteins per sample from plasma of patients with various cancers and diseases [27][28][29][30][31]. Due to a limited number of spectrally nonoverlapping fluorophores, higher multiplicity proteomic profiling of material collected on the DEP chip was previously unattainable.…”

Sensory sensitivity after acquired brain injury: A systematic review

“…Seven studies related atypical sensory sensitivity to structural brain abnormalities. Likova and Tyler (2018) reported pontine degeneration in mTBI patients who expressed being hypersensitive to light and Lewis et al (2020) concluded that biomarkers indicative of cellular and axonal damage (i.e. blood plasma level of ubiquitin C-terminal hydrolase L1 and glial fibrillary acidic protein) correlated with both light and noise sensitivity.…”