A Set of Diagnostic Tests for Detection of Active Babesia duncani Infection

Human babesiosis is a rapidly emerging and potentially fatal tick-borne disease caused by intraerythrocytic apicomplexan parasites of the Babesia genus. Among the various species of Babesia that infect humans, B. duncani has been found to cause severe and life-threatening infections. Detection of active B. duncani infection is critical for accurate diagnosis and effective management of the disease. While molecular assays for the detection of B. duncani infection in blood are available, a reliable strategy to detect biomarkers of active infection has not yet been developed. Here, we report the development of the first B. duncani antigen capture assays that rely on the detection of two B. duncani -exported immunodominant antigens, BdV234 and BdV38. The assays were validated using blood samples from cultured parasites in human erythrocytes and B. duncani -infected laboratory mice at different parasitemia levels and following therapy. The assays display high specificity with no cross-reactivity with B. microti , B. divergens , Babesia MO1, or P. falciparum. The assay also demonstrates high sensitivity, detecting as low as 115 infected erythrocytes/µl of blood. Screening of 1,731 blood samples from diverse biorepositories, including previously identified Lyme and/or B. microti positive human samples and new specimens from field mice, showed no evidence of B. duncani infection in these samples. The assays could be useful in diverse diagnostic scenarios, including point-of-care testing for early B. duncani infection detection in patients, field tests for screening reservoir hosts, and high-throughput screening such as blood collected for transfusion.

Short summary

We developed two ELISA-based assays, BdACA38 and BdACA234, for detecting B. duncani , a potentially fatal tick-borne parasite causing human babesiosis. The assays target two immunodominant antigens, BdV234 and BdV38, demonstrating high specificity (no cross-reactivity with other Babesia species or Plasmodium falciparum ) and sensitivity (detecting as low as 115 infected erythrocytes/µl). The assays were validated using in vitro-cultured parasites and infected mice. Screening diverse blood samples showed no evidence of B. duncani active infection among 1,731 human and field mice blood samples collected from the north-eastern, midwestern, and western US. These assays offer potential in diverse diagnostic scenarios, including early patient detection, reservoir animal screening, and transfusion-transmitted babesiosis prevention.

Molecular and functional profiling of chemotolerant cells unveils nucleoside metabolism-dependent vulnerabilities in medulloblastoma

Chemotherapy resistance is considered one of the main causes of tumor relapse, still challenging researchers for the identification of the molecular mechanisms sustaining its emergence. Here, we setup and characterized chemotherapy-resistant models of Medulloblastoma (MB), one of the most lethal pediatric brain tumors, to uncover targetable vulnerabilities associated to their resistant phenotype. Integration of proteomic, transcriptomic and kinomic data revealed a significant deregulation of several pathways in resistant MB cells, converging to cell metabolism, RNA/protein homeostasis, and immune response, eventually impacting on patient outcome. Moreover, resistant MB cell response to a large library of compounds through a high-throughput screening (HTS), highlighted nucleoside metabolism as a relevant vulnerability of chemotolerant cells, with peculiar antimetabolites demonstrating increased efficacy against them and even synergism with conventional chemotherapeutics. Our results suggest that drug-resistant cells significantly rewire multiple cellular processes, allowing their adaptation to a chemotoxic environment, nevertheless exposing alternative actionable susceptibilities for their specific targeting.

Detection of toxoplasmic encephalitis in HIV positive patients in urine with hydrogel nanoparticles

BACKGROUND

Diagnosis of toxoplasmic encephalitis (TE) is challenging under the best clinical circumstances. The poor clinical sensitivity of quantitative polymerase chain reaction (qPCR) for Toxoplasma in blood and CSF and the limited availability of molecular diagnostics and imaging technology leaves clinicians in resource-limited settings with few options other than empiric treatment.

METHOLOGY/PRINCIPLE FINDINGS

Here we describe proof of concept for a novel urine diagnostics for TE using Poly-N-Isopropylacrylamide nanoparticles dyed with Reactive Blue-221 to concentrate antigens, substantially increasing the limit of detection. After nanoparticle-concentration, a standard western blotting technique with a monoclonal antibody was used for antigen detection. Limit of detection was 7.8pg/ml and 31.3pg/ml of T. gondii antigens GRA1 and SAG1, respectively. To characterize this diagnostic approach, 164 hospitalized HIV-infected patients with neurological symptoms compatible with TE were tested for 1) T. gondii serology (121/147, positive samples/total samples tested), 2) qPCR in cerebrospinal fluid (11/41), 3) qPCR in blood (10/112), and 4) urinary GRA1 (30/164) and SAG1 (12/164). GRA1 appears to be superior to SAG1 for detection of TE antigens in urine. Fifty-one HIV-infected, T. gondii seropositive but asymptomatic persons all tested negative by nanoparticle western blot and blood qPCR, suggesting the test has good specificity for TE for both GRA1 and SAG1. In a subgroup of 44 patients, urine samples were assayed with mass spectrometry parallel-reaction-monitoring (PRM) for the presence of T. gondii antigens. PRM identified antigens in 8 samples, 6 of which were concordant with the urine diagnostic.

CONCLUSION/SIGNIFICANCES

Our results demonstrate nanoparticle technology's potential for a noninvasive diagnostic test for TE. Moving forward, GRA1 is a promising target for antigen based diagnostics for TE.

Extracellular vesicles from HTLV-1 infected cells modulate target cells and viral spread

BACKGROUND

The Human T-cell Lymphotropic Virus Type-1 (HTLV-1) is a blood-borne pathogen and etiological agent of Adult T-cell Leukemia/Lymphoma (ATLL) and HTLV-1 Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP). HTLV-1 has currently infected up to 10 million globally with highly endemic areas in Japan, Africa, the Caribbean and South America. We have previously shown that Extracellular Vesicles (EVs) enhance HTLV-1 transmission by promoting cell-cell contact.

RESULTS

Here, we separated EVs into subpopulations using differential ultracentrifugation (DUC) at speeds of 2 k (2000×g), 10 k (10,000×g), and 100 k (100,000×g) from infected cell supernatants. Proteomic analysis revealed that EVs contain the highest viral/host protein abundance in the 2 k subpopulation (2 k > 10 k > 100 k). The 2 k and 10 k populations contained viral proteins (i.e., p19 and Tax), and autophagy proteins (i.e., LC3 and p62) suggesting presence of autophagosomes as well as core histones. Interestingly, the use of 2 k EVs in an angiogenesis assay (mesenchymal stem cells + endothelial cells) caused deterioration of vascular-like-tubules. Cells commonly associated with the neurovascular unit (i.e., astrocytes, neurons, and macrophages) in the blood-brain barrier (BBB) showed that HTLV-1 EVs may induce expression of cytokines involved in migration (i.e., IL-8; 100 k > 2 k > 10 k) from astrocytes and monocyte-derived macrophages (i.e., IL-8; 2 k > 10 k). Finally, we found that EVs were able to promote cell-cell contact and viral transmission in monocytic cell-derived dendritic cell. The EVs from both 2 k and 10 k increased HTLV-1 spread in a humanized mouse model, as evidenced by an increase in proviral DNA and RNA in the Blood, Lymph Node, and Spleen.

CONCLUSIONS

Altogether, these data suggest that various EV subpopulations induce cytokine expression, tissue damage, and viral spread.

Evaluation of pathogen specific urinary peptides in tick-borne illnesses

Mass spectrometry enhanced by nanotechnology can achieve previously unattainable sensitivity for characterizing urinary pathogen-derived peptides. We utilized mass spectrometry enhanced by affinity hydrogel particles (analytical sensitivity = 2.5 pg/mL) to study tick pathogen-specific proteins shed in the urine of patients with (1) erythema migrans rash and acute symptoms, (2) post treatment Lyme disease syndrome (PTLDS), and (3) clinical suspicion of tick-borne illnesses (TBI). Targeted pathogens were Borrelia, Babesia, Anaplasma, Rickettsia, Ehrlichia, Bartonella, Francisella, Powassan virus, tick-borne encephalitis virus, and Colorado tick fever virus. Specificity was defined by 100% amino acid sequence identity with tick-borne pathogen proteins, evolutionary taxonomic verification for related pathogens, and no identity with human or other organisms. Using a cut off of two pathogen peptides, 9/10 acute Lyme Borreliosis patients resulted positive, while we identified zero false positive in 250 controls. Two or more pathogen peptides were identified in 40% of samples from PTLDS and TBI patients (categories 2 and 3 above, n = 59/148). Collectively, 279 distinct unique tick-borne pathogen derived peptides were identified. The number of pathogen specific peptides was directly correlated with presence or absence of symptoms reported by patients (ordinal regression pseudo-R2 = 0.392, p = 0.010). Enhanced mass spectrometry is a new tool for studying tick-borne pathogen infections.

Proteomic analysis reveals pathogen-derived biomarkers of acute babesiosis in erythrocytes, plasma, and urine of infected hamsters

Babesiosis among humans is on the rise in North America. Current diagnostic assays for the screening of babesiosis require blood collection by venipuncture, which is an invasive method. Urine on the other hand is a desirable biospecimen for biomarker analysis of Babesia microti infections because it can be collected periodically and non-invasively. Our group uses a new class of biomarker harvesting nanocage technology, which, when combined with mass spectrometry (MS), can determine the presence of parasite proteins shed in different bodily fluids of mammalian hosts, including urine. Using the hamster model of babesiosis, our nanoparticle-MS approach identified several B. microti proteins in erythrocytes, plasma, and urine samples. Surface and secreted antigens previously shown to elicit host immune responses against the parasite were particularly abundant in erythrocytes and plasma compared to other proteins. Two of these antigens, BmSA1 and BMR1_03g00947, showed different localization patterns by immunofluorescence of infected erythrocytes. Hamster urine samples from parasitemic animals harbored lower numbers of B. microti proteins compared to erythrocytes and plasma, with glycolytic enzymes, cytoskeletal components, and chaperones being the most frequently detected proteins. By applying novel nanoparticle-MS methods, a high level of analytical sensitivity can be achieved to detect multiple B. microti proteins in blood and urine. This is generally difficult to obtain with other techniques due to the masking of parasite biomarkers by the complex biomolecular matrix of bodily fluids from the host.

Analysis of the Babesia microti proteome in infected red blood cells by a combination of nanotechnology and mass spectrometry

Proteomics of Babesia microti has lagged behind other apicomplexans despite recent genome and transcriptome studies. Here, we used a combination of nanotechnology and mass spectrometry to provide a proteomic profile of B. microti acute infection. We identified ∼500 parasite proteins in blood with functions such as transport, carbohydrate and energy metabolism, proteolysis, DNA and RNA metabolism, signaling, translation, lipid biosynthesis, and motility and invasion. We also identified surface antigens with roles in the immune response to the parasite. This first evaluation of the B. microti proteome in erythrocytes provides information for the study of intracellular survival and development of diagnostic tools using mass spectrometry.

Urine lipoarabinomannan glycan in HIV-negative patients with pulmonary tuberculosis correlates with disease severity

An accurate urine test for pulmonary tuberculosis (TB), affecting 9.6 million patients worldwide, is critically needed for surveillance and treatment management. Past attempts failed to reliably detect the mycobacterial glycan antigen lipoarabinomannan (LAM), a marker of active TB, in HIV-negative, pulmonary TB–infected patients’ urine (85% of 9.6 million patients). We apply a copper complex dye within a hydrogel nanocage that captures LAM with very high affinity, displacing interfering urine proteins. The technology was applied to study pretreatment urine from 48 Peruvian patients, all negative for HIV, with microbiologically confirmed active pulmonary TB. LAM was quantitatively measured in the urine with a sensitivity of >95%and a specificity of >80% (n = 101) in a concentration range of 14 to 2000 picograms per milliliter, as compared to non-TB, healthy and diseased, age-matched controls (evaluated by receiver operating characteristic analysis; area under the curve, 0.95; 95% confidence interval, 0.9005 to 0.9957). Urinary LAM was elevated in patients with a higher mycobacterial burden (n = 42), a higher proportion of weight loss (n = 37), or cough (n = 50). The technology can be configured in a variety of formats to detect a panel of previously undetectable very-low-abundance TB urinary analytes. Eight of nine patients who were smear-negative and culture-positive for TB tested positive for urinary LAM. This technology has broad implications for pulmonary TB screening, transmission control, and treatment management for HIV-negative patients.

Proteomic analysis of cerebrospinal fluid from children with central nervous system tumors identifies candidate proteins relating to tumor metastatic spread

Central nervous system (CNS) tumors are the most common solid tumors in childhood. Since the sensitivity of combined cerebrospinal fluid (CSF) cytology and radiological neuroimaging in detecting meningeal metastases remains relatively low, we sought to characterize the CSF proteome of patients with CSF tumors to identify biomarkers predictive of metastatic spread. CSF samples from 27 children with brain tumors and 13 controls (extra-CNS non-Hodgkin lymphoma) were processed using core-shell hydrogel nanoparticles, and analyzed with reverse-phase liquid chromatography/electrospray tandem mass spectrometry (LC-MS/MS). Candidate proteins were identified with Fisher's exact test and/or a univariate logistic regression model. Reverse phase protein array (RPPA), Western blot (WB), and ELISA were used in the training set and in an independent set of CFS samples (60 cases, 14 controls) to validate our discovery findings. Among the 558 non-redundant proteins identified by LC-MS/MS, 147 were missing from the CSF database at http://www.biosino.org. Fourteen of the 26 final top-candidate proteins were chosen for validation with WB, RPPA and ELISA methods. Six proteins (type 1 collagen, insulin-like growth factor binding protein 4, procollagen C-endopeptidase enhancer 1, glial cell-line derived neurotrophic factor receptor α2, inter-alpha-trypsin inhibitor heavy chain 4, neural proliferation and differentiation control protein-1) revealed the ability to discriminate metastatic cases from controls. Combining a unique dataset of CSFs from pediatric CNS tumors with a novel enabling nanotechnology led us to identify CSF proteins potentially related to metastatic status.

Affinity enrichment for mass spectrometry: improving the yield of low abundance biomarkers

INTRODUCTION

Mass spectrometry (MS) is the premier tool for discovering novel disease-associated protein biomarkers. Unfortunately, when applied to complex body fluid samples, MS has poor sensitivity for the detection of low abundance biomarkers (≪10 ng/mL), derived directly from the diseased tissue cells or pathogens. Areas covered: Herein we discuss the strengths and drawbacks of technologies used to concentrate low abundance analytes in body fluids, with the aim to improve the effective sensitivity for MS discovery. Solvent removal by dry-down or dialysis, and immune-depletion of high abundance serum or plasma proteins, is shown to have disadvantages compared to positive selection of the candidate biomarkers by affinity enrichment. A theoretical analysis of affinity enrichment reveals that the yield for low abundance biomarkers is a direct function of the binding affinity (Association/Dissociation rates) used for biomarker capture. In addition, a high affinity capture pre processing step can effectively dissociate the candidate biomarker from partitioning with high abundance proteins such as albumin. Expert commentary: Properly designed high affinity capture materials can enrich the yield of low abundance (0.1-10 picograms/mL) candidate biomarkers for MS detection. Affinity capture and concentration, as an upfront step in sample preparation for MS, combined with MS advances in software and hardware that improve the resolution of the chromatographic separation can yield a transformative new class of low abundance biomarkers predicting disease risk or disease latency.

The development of episodic future thinking in middle childhood

The ability to imagine future events (episodic future thinking-EFT) emerges in preschoolers and further improves during middle childhood and adolescence. In the present study, we focused on the possible cognitive factors that affect EFT and its development. We assessed the ability to mentally project forward in time of a large cohort of 135 6- to 11-year-old children through a task with minimal narrative demands (the Picture Book Trip task adapted from Atance and Meltzoff in Cogn Dev 20(3):341-361. doi:10.1016/j.cogdev.2005.05.001, 2005) in order to avoid potential linguistic effects on children's performance. The results showed that this task can be used to assess the development of EFT at least until the age of 8. Furthermore, EFT scores correlated with measures of phonological short-term and verbal working memory. These results support the possibility that cognitive factors such as working memory play a key role in EFT.

Brief Report: Self-Based and Mechanical-Based Future Thinking in Children with Autism Spectrum Disorder

This brief report is a partial replication of the study by Jackson and Atance (J Dev Disabil 14:40-45, 2008) assessing nonverbal Self-based and Mechanical-based future thinking (FT) in children with Autism Spectrum Disorder (ASD). In a first step, these tasks were administered to 30 children with ASD. The two Self-based tasks were then modified as a verbal component could not be completely ruled out. Consequently, 77 children with ASD and 77 children with typical development received the modified Self-based FT tasks and the Mechanical-based FT tasks. We partially replicated the previous findings. Participants with ASD had impaired FT in both kinds of tasks and both groups performed better on tasks assessing Mechanical-based FT than Self-based FT. These results suggest that impairments of FT in ASD are not limited to Self-Projection.

Application of Hydrogel Nanoparticles for the Capture, Concentration, and Preservation of Low-Abundance Biomarkers

In the recent years, a lot of emphasis has been placed on the discovery and detection of clinically relevant biomarkers. Biomarkers are crucial for the early detection of several diseases, and they play an important role in the improvement of current treatments, thus reducing patient mortality rate. Because biofluids account to 60% of the body mass, they represent a goldmine of significant biomarkers. Unfortunately, because of their low concentration in body fluids, their lability, and the presence of high abundance proteins (i.e., albumin and immunoglobulins), low abundance biomarkers are difficult to detect with mass spectrometry or immunoassays. Nanoparticles made of poly(N-isopropylacrylamide) (NIPAm) and functionalized with affinity reactive baits allow researchers to overcome these physiological barriers and in one single step capture, concentrate, and preserve labile biomarkers in complex body fluids (i.e. urine, blood, sweat, CSF). Although hydrogel nanoparticles have been largely studied and used as a drug delivery tool, our application focuses on their capturing abilities instead of the releasing of specific drug molecules. Once the functionalized nanoparticles are incubated with a biological fluid, small biomarkers are captured by the affinity baits while unwanted high abundance analytes are excluded. The potentially relevant biomarkers are then concentrated into small volumes. The concentration factor (up to 10,000-fold) successfully enhances the detection sensitivity of mass spectrometry and immunoassays allowing the detection of previously invisible proteins.

Abstract 1874: Investigation of the cerebrospinal fluid proteome from central nervous system pediatric tumors using bait loaded hydrogel nanoparticles and mass spectrometry

Central nervous system (CNS) tumors are the second common pediatric malignancies, accounting for approximately 25% of all childhood neoplasms. Cerebrospinal fluid (CSF) is a very valuable source of biomarkers for brain tumors and represents a potential indicator of pathological processes that happen in the CNS. CSF biomarker discovery poses some physiological and technical challenges: low protein levels (total protein concentration 0.3 to 0.7 mg/mL), dynamic range (up to approximately 12 order of magnitude), and the presence of highly abundant proteins masking the less abundant ones. In order to overcome these challenges, we used core-shell capturing hydrogel nanoparticles that can capture, preserve and concentrate candidate low molecular weight, low abundance proteins in solution in one step improving the effective sensitivity of mass-spectrometry by several orders of magnitude. CSF samples from pediatric brain cancer patients (14 medulloblastoma, 4 high-grade glioma, 6 ependimoma, 4 PNET, 2 atypical teratoid rhabdoid tumor) either at initial diagnosis (n=27) or at tumor recurrence (n=3) and 21 non-brain pediatric oncology controls (extra-CNS non Hodgkin lymphoma) were processed with core-shell hydrogel nanoparticles and then analyzed with reverse-phase liquid chromatography/electrospray tandem mass spectrometry (MS/MS). We identified 559 non redundant proteins, 147 (26%) of those not present in the public comprehensive CSF proteome database (www.biosino.org). Functional classification analysis performed with IPA Ingenuity System showed that CSF contained proteins normally involved in neurological diseases, developmental disorders, cellular movement, cellular growth and proliferation. Several candidate proteins that show a statistical difference (p-value <0.05, Fisher test) between brain tumor and non-brain oncology controls, were involved in the process of extracellular matrix (ECM) remodeling which has a key role in the transition to invasive cancer and is often an indicator of worse prognosis. Two examples were a) the ECM protein collagen XVIII, which was previously identified in meningioma tissue with a fast progression, and b) procollagen C-endopeptidase enhancer, an extracellular matrix glycoprotein related to tumor growth and angiogenesis. Statistical analysis between non-metastatic and metastatic patient samples also highlighted potentially relevant proteins such as GDNF family receptor α-2 (GFRα2); two other family members GFRα1 and GFRα3 were reported to have a role in tumor growth and invasiveness. In conclusion, combining a unique dataset of CSF from pediatric cancer patients with a novel enabling nanotechnology allowed us to identify important insights for diagnosis, prognosis and molecular stratification of CNS pediatric tumors.

Citation Format: Ruben Magni, Paolo Verderio, Lance Liotta, Filippo Spreafico, Maura Massimino, Alessandra Luchini, Italia Bongarzone. Investigation of the cerebrospinal fluid proteome from central nervous system pediatric tumors using bait loaded hydrogel nanoparticles and mass spectrometry. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1874. doi:10.1158/1538-7445.AM2014-1874

Hydrogel nanoparticle harvesting of plasma or urine for detecting low abundance proteins

Novel biomarker discovery plays a crucial role in providing more sensitive and specific disease detection. Unfortunately many low-abundance biomarkers that exist in biological fluids cannot be easily detected with mass spectrometry or immunoassays because they are present in very low concentration, are labile, and are often masked by high-abundance proteins such as albumin or immunoglobulin. Bait containing poly(N-isopropylacrylamide) (NIPAm) based nanoparticles are able to overcome these physiological barriers. In one step they are able to capture, concentrate and preserve biomarkers from body fluids. Low-molecular weight analytes enter the core of the nanoparticle and are captured by different organic chemical dyes, which act as high affinity protein baits. The nanoparticles are able to concentrate the proteins of interest by several orders of magnitude. This concentration factor is sufficient to increase the protein level such that the proteins are within the detection limit of current mass spectrometers, western blotting, and immunoassays. Nanoparticles can be incubated with a plethora of biological fluids and they are able to greatly enrich the concentration of low-molecular weight proteins and peptides while excluding albumin and other high-molecular weight proteins. Our data show that a 10,000 fold amplification in the concentration of a particular analyte can be achieved, enabling mass spectrometry and immunoassays to detect previously undetectable biomarkers.

Abstract 1080: Nanotechnology-enhanced proteomics analysis of a unique prospective collection of blood samples for the discovery and validation of early detection biomarkers for Non-Small Cell Lung Cancer (NSCLC)

BACKGROUND. Early identification of individuals at high risk to develop lung cancer would be a crucial requirement for a successful prevention strategy. The novelty of this study lies in our ability to discover and validate biomarkers for subclinical disease in blood samples obtained from healthy individuals up to 25 years prior to lung cancer diagnosis. Plasma samples were collected from healthy individuals who later developed Non-Small Cell Lung Cancer (NSCLC) (cases) matched with individuals who did not develop cancer after the same period of follow up (controls). We studied the influence of smoking status (non-smokers, smokers and former smokers) on the pattern of blood borne biomarkers in order to test the hypothesis that the developing tumor might have distinct molecular origins in the three classes.

METHODS. Study subjects were drawn from the longitudinal Physicians’ Health Study (PHS). We analyzed plasma samples from 42 cases and 42 controls (16 to 284 month follow up). Small proteins and peptides were purified from plasma using N-isopropylacrylamide (NIPAm) core shell hydrogel particles functionalized with Cibacron blue F3GA and vinylsulfonic acid as chemical baits. Proteins eluted from the particles were analyzed using LTQ-Orbitrap mass spectrometer (Thermo Fisher).

RESULTS. 67, 83 and 75 candidate biomarkers of early NSCLC were identified for non-smokers, former smokers and smokers, respectively. An optimal combination of predictive biomarkers was selected for each group. Receiver-operating characteristic (ROC) curves were utilized to evaluate the predictive value of selected biomarkers. In non-smokers, a panel of 8 proteins including Keratin 6B and endostatin had 82% sensitivity and 91% specificity (AUC 0.926) in predicting an individual developing cancer. In former smokers, a combination of 8 proteins (including malic enzyme 2 and mitochondrial malate dehydrogenase) had 88% sensitivity and 82% specificity (AUC 0.901). In smokers, 10 selected biomarkers (including fructose-bisphosphate aldolase A and glyceraldehyde-3-phosphate dehydrogenase) had 75% sensitivity and 75% specificity (AUC 0.833). Differential plasma protein profiles of smokers or former smokers that developed cancer included a high number of proteins involved in the response to high oxidative stress. Oxidative stress, together with inflammation, could be the driving pre requisite for lung cancer development in individuals exposed to smoke. Interestingly, endostatin (a known inhibitor of angiogenesis) was over-represented (Chi-Square p < 0.031) in cases versus controls independent of smoking status. The predictive value of identified candidate biomarkers will be verified in a larger cohort of independent blinded samples from the same prospective collection study.

Citation Format: Claudia Fredolini, Alessandra Luchini, Luisa Paris, Ruben Magni, Emanuel F. Petricoin, Salima Darakjy, J. Michael Gaziano, Howard D. Sesso, Lance A. Liotta, Frederica P. Perera. Nanotechnology-enhanced proteomics analysis of a unique prospective collection of blood samples for the discovery and validation of early detection biomarkers for Non-Small Cell Lung Cancer (NSCLC). [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1080. doi:10.1158/1538-7445.AM2013-1080

A tag-less method for direct isolation of human umbilical vein endothelial cells by gravitational field-flow fractionation

The analysis of cellular and molecular profiles represents a powerful tool in many biomedical applications to identify the mechanisms underlying the pathological changes. The improvement of cellular starting material and the maintenance of the physiological status in the sample preparation are very useful. Human umbilical vein endothelial cells (HUVEC) are a model for prediction of endothelial dysfunction. HUVEC are enzymatically removed from the umbilical vein by collagenase. This method provides obtaining a good sample yield. However, the obtained cells are often contaminated with blood cells and fibroblasts. Methods based on negative selection by in vitro passages or on the use of defined marker are currently employed to isolate target cells. However, these approaches cannot reproduce physiological status and they require expensive instrumentation. Here we proposed a new method for an easy, tag-less and direct isolation of HUVEC from raw umbilical cord sample based on the gravitational field-flow fractionation (GrFFF). This is a low-cost, fully biocompatible method with low instrumental and training investments for flow-assisted cell fractionation. The method allows obtaining pure cells without cell culture procedures as starting material for further analysis; for example, a proper amount of RNA can be extracted. The approach can be easily integrated into clinical and biomedical procedures.

Application of Analyte Harvesting Nanoparticle Technology to the Measurement of Urinary HGH in Healthy Individuals

Urine represents a valuable biofluid for noninvasive measurement of Human Growth Hormone (HGH) secretion. Unfortunately, currently available commercial HGH immunoassays do not achieve the sensitivity needed for urinary HGH measurement in the low picogram per milliliter range, the expected normal concentration range of HGH in urine. A nanotechnology based sample preprocessing step was used to extract and concentrate HGH in urine so that urinary HGH could be measured with a clinical grade standard immunoassay designed for serum (Immulite 1000, Siemens). We applied the nanoparticle enhanced immunoassay to evaluate the baseline value of urinary HGH in a population of healthy young adults (age 18-30, N=33, median 21, M: F=39%:61%, with no reported medical therapies). Nanoparticle sample preprocessing effectively improved the lower limit of detection of the Immulite HGH assay by more than 50 fold, shifting the linear range of the assay to encompass the expected value of urinary HGH. The full process between run and within run CV% was 7.9 and 9.0%, respectively. On 33 healthy volunteers, the 95% reference values for hGH in spot urine normalized to specific gravity were 0.64 - 16.85 pg/mL (0.05-5.82 ng/g creatinine). Nanoparticle preprocessing constitutes a reliable means of measuring urinary HGH with a clinical grade immunoassay, now establishing a normal baseline value for HGH in urine. Nanoparticles can be used to study the kinetics of HGH excretion in urine, and the factors that influence urinary HGH secretion and HGH isoform proportions.

Electro-oculographic abnormality in eyes with uveal melanoma

PURPOSE

To seek out correlations between preoperative electro-oculogram (EOG) recordings with different types of uveal melanomas, after surgery.

METHODS

We analysed the EOG recordings of 120 patients with uveal melanomas, histologically verified, 100 in the choroid and 20 in the iris and ciliary body. The EOG data were correlated with the site, size and histological type of the tumor.

RESULTS

In 100 eyes with choroidal melanoma the Arden Index (AI) was less than in fellow eyes (mean 126.6, SD +/- 23.8 and 202.9, SD +/- 47.0; p=0.01). The EOG values were not different with respect to the histological type, site and size of tumor. In cases with iris and ciliary body melanomas the AI were not significantly different from the fellow eyes (mean 180.6, SD +/- 23.6 and 203.2, SD +/- 38.7; p=0.07).

CONCLUSIONS

Since the EOG is abnormal in eyes with choroidal melanoma, it can be considered a powerful auxiliary for diagnosing these tumors.

Unilateral retinitis pigmentosa: clinical and electrophysiological report of four cases

Unilateral retinitis pigmentosa (URP) is a rare tapetoretinal dystrophy affecting only one eye. The François and Verriest criteria are necessary to make a correct diagnosis of URP: exclude all infective etiologies, check that the clinical signs of retinitis are present in the affected eye and ensure the total absence of any signs or symptoms of retinitis pigmentosa in the fellow eye. The standard electroretinogram and standard electro-oculogram are very useful for the correct diagnosis. Other pigmentary retinopathies simulating retinitis pigmentosa have to be excluded, such as previous retinal inflammatory diseases like syphilis, rubeola, other viral diseases and onchocerciasis. In this paper, 4 cases of URP are reported.

Electronystagmographic investigation in X-linked ocular albinism

Albinism represents the most frequent cause of nystagmus induced by visual sensory disorders. We studied five patients aged between three and five years with ocular albinism with the aim of identifying the characteristics of nystagmic oscillations. The patients underwent complete ophthalmological examination and electronystagmography (ENG). ENG revealed either pendular or jerk waveforms (or both) with the same complex effects of fixation seen in those with idiopathic congenital nystagmus. Three children presented face turn due to reduced severity of nystagmus in lateroversion. Latent nystagmus was not observed.

Effect of myopic excimer laser photorefractive keratectomy on the electrophysiologic function of the retina and optic nerve

PURPOSE

To assess by electrophysiologic testing the effect of photorefractive keratectomy (PRK) on the retina and optic nerve.

SETTING

Eye Clinic, S. Salvatore Hospital, L'Aquila University, Italy.

METHODS

Standard pattern electroretinograms (P-ERGs) and standard pattern visual evoked potentials (P-VEPs) were done in 25 eyes of 25 patients who had myopic PRK for an attempted correction between 5.00 and 15.00 diopters (D) (mean 8.00 D). Testing was done preoperatively and 3, 6, 12, and 18 months postoperatively. The contralateral eyes served as controls. During the follow-up, 3 patients (12%) developed steroid-induced elevated intraocular pressure (IOP) that resolved after corticosteroid therapy was discontinued.

RESULTS

No statistically significant differences were seen between treated and control eyes nor between treated eyes preoperatively and postoperatively.

CONCLUSION

Myopic excimer laser PRK did not seem to affect the posterior segment. The transient steroid-induced IOP rise did not seem to cause functional impairment.

Homonymous Bilateral Hemianopsia: Electrophysiological Study of a Case

Described is a case of bilateral homonymous hemianopsia with macular sparing, resulting from head trauma. The case presented lesions of the occipital visual areas which involved entirely the left hemisphere and only partially the right hemisphere. VEP were obtainable only from electrodes placed on the right hemisphere with both right eye and left eye stimulation. VEP mapping showed that each eye projects macular fibres towards functional areas of the right occipital hemisphere.

Electrophysiological examination confirmed objectively and for the first time in man the theory of “double cortical macular representation”.

Clinical implications of this finding are discussed.

Assessment of visual contrast sensitivity in hyperbaric oxygen

Hyperbaric oxygen therapy is used in ophthalmology in ischemic pathologies of the anterior and posterior segments. Our experiment was done on a healthy group of volunteers aged between 10 and 50 yr. We examined the subject's vision before and after acute HBO exposure (60 min at 2.5 atm abs with pure oxygen) to verify whether vasoconstriction induced by hyperoxemia can influence eyesight. We measured the psychophysical determination of the threshold contrast according to Maione-Maffei's zebra test. The results demonstrated that contrast sensitivity is significantly improved for almost all the studied frequencies in normal subjects after acute HBO exposure. We hypothesize that the visual system has a reserve which is activated by an improvement of retinal oxygenation.

Single-sweep analysis using an autoregressive with exogenous input (ARX) model

Single-sweep visual evoked potential analysis would be useful in clinical electrophysiology practice because it would make possible the evaluation of transient phenomena, but recording single-sweep visual evoked potentials is difficult because of the low signal-noise ratio. To increase this ratio we used a filter based on an autoregressive with exogenous input model. We studied a group of 12 diabetic patients matched with a control group of 14 normal subjects. The model, in most cases, allowed us to extrapolate the P100 component from each single sweep of visual evoked potential. The visual evoked potential values obtained by means of averaging were not significantly different in the groups studied, but single-sweep analysis showed different distribution of the P100 component amplitude. The preliminary results of our study evidenced differences in the amplitude and latency distribution of normal and diabetic subjects, thus confirming the power of this new technique and its ability to obtain some information that is masked by the averaging method.

Electroretinographic findings in congenital oculomotor apraxia (Cogan's syndrome)

We performed visual evoked potential testing and electroretinography in five patients with Cogan's oculomotor apraxia. The visual evoked potentials were normal, confirming previously reported data. Electroretinograms were abnormal in two of the five patients examined. A previous study showed normal electroretinogram responses bilaterally in one patient. Our findings suggest the existence of two variants of the syndrome; the one with electroretinogram anomalies has a worse visual prognosis.

Best's multiple vitelliform degeneration

Best's disease with multifocal lesions is rare. The authors describe four cases of multifocal vitelliform disease. The fluorescein angiographic features of macular and extramacular lesions are considered. Different stages of evolution may be present between central and extramacular lesions.

Corneal endothelial anomalies in the fetal alcohol syndrome

The fetal alcohol syndrome involves various neural crest-derived structures thus causing systemic and ocular malformations. This study investigated anomalies of the corneal endothelium, a neural crest-derived tissue, in eight children affected by fetal alcohol syndrome without known anterior segment anomalies. We performed specular biomicroscopy on the central corneal endothelium. The data were then compared with those from 80 age-matched healthy children, applying the same methods. Significant differences were found between patients with fetal alcohol syndrome and healthy subjects for mean cell density (P = .032), polymegethism (P = .000), and percentage of hexagonal cells (P = .000). We also found a close correlation between endothelial anomalies and auditory dysfunction in the patients with fetal alcohol syndrome. These alterations may be a consequence of alcohol-induced toxic effects on neural crest cells destined to form both the corneal endothelium and the organ of Corti in the same embryogenic period.

Microphthalmos with colobomatous orbital cyst in trisomy 13

The authors describe a case of trisomy 13 with microphthalmos and colobomatous cyst of the optic nerve and of the chorioretina with orbital extension, in a six-month-old female patient. The colobomatous cyst has been studied by means of computerized axial tomography and ultrasonography in order to follow its evolution. The orbital cyst has not increased in size.

Carotid occlusive disease: an electrophysiological macular investigation

Thirteen patients with carotid stenosis were studied by the authors by the measuring the Visual Evoked Potentials (VEPs) before and after thromboendarterectomy. This test of retinal function measures the recovery time of the amplitude of the major positive peak (P100) after photostress. When compared to that we observed in controls, we found, a significant increase of the P100 recovery time in patients suffering from carotid disease with severe stenosis. The method proved suitable for the functional evaluation of the vascular reconstruction of the carotid area, since four weeks after surgery a physiological recovery of the amplitude of VEP was observed. This method is proposed by the authors for the long-term functional evaluation of patients subjected to carotid thromboendarterectomy for tight stenosis of the carotid bifurcation.

VEP pattern after photostress: an index of macular function

Eighty-seven subjects were examined by means of visual evoked potentials (VEPs) to evaluate the recovery time of the amplitude of the pattern VEP after photostress. Twenty-eight subjects were normal and 59 patients were affected by carotid occlusive disease, vascular retinopathies with and without macular involvement, and connective tissue diseases treated with antimalarial drugs. This examination method emphasizes visual dysfunction in a stage where ophthalmological changes are absent or minimal and therefore may be a useful test for the investigation of macular function.