Development of bead based multiplexed immunoassay for evaluation of midkine, syndecan-1, and ANGPTL4 in patient serum.

BACKGROUND: Angiogenesis is associated with tumor progression in a range of malignancies. Herein, we develop custom immunobead assays for several mechanistically important targets and evaluated these against sera from cohorts of non-small cell lung cancer (NSCLC) patients. METHODS: Antigen "capture" antibodies for midkine, syndecan-1, and ANGPTL4 were independently conjugated to MagPlex® Microspheres using standard carbodiimide/NHS-based chemistry. These reagents served as the basis for quantitative sandwich assay assembly using biotinylated detection antibodies and R-phycoerythrin-conjugated streptavidin reporter system. Standard curves were created using dilution series of recombinant target proteins with assay performance characteristics calculated, accordingly. Finally, we evaluated a range of serum samples from NSCLC patients (n = 32) to verify assay performance. RESULTS: Multiplexed assays for midkine, syndecan-1, and ANGPTL4 were developed with three orders of magnitude in dynamic range, excellent intra- and inter-assay precision, and accuracy parameters (<10%, and <15% variability, respectively). Detection and quantifications limits were suitable for the three assays to efficiently evaluate sera across a range of disease stages with a four-fold dilution factor. CONCLUSION: We successfully developed and analytically validated a 3-plex immunobead assay for quantifying midkine, syndecan-1, and ANGPTL4 in patient sera. This multiplexed assay will provide an important tool for future studies delineating the role of angiogenesis in lung cancer progression.

Zucker Diabetic-Sprague Dawley Rats Have Impaired Peri-Implant Bone Formation, Matrix Composition, and Implant Fixation Strength.

An increasing number of patients with type 2 diabetes (T2DM) will require total joint replacement (TJR) in the next decade. T2DM patients are at increased risk for TJR failure, but the mechanisms are not well understood. The current study used the Zucker Diabetic-Sprague Dawley (ZDSD) rat model of T2DM with Sprague Dawley (SPD) controls to investigate the effects of intramedullary implant placement on osseointegration, peri-implant bone structure and matrix composition, and fixation strength at 2 and 10 weeks post-implant placement. Postoperative inflammation was assessed with circulating MCP-1 and IL-10 2 days post-implant placement. In addition to comparing the two groups, stepwise linear regression modeling was performed to determine the relative contribution of glucose, cytokines, bone formation, bone structure, and bone matrix composition on osseointegration and implant fixation strength. ZDSD rats had decreased peri-implant bone formation and reduced trabecular bone volume per total volume compared with SPD controls. The osseointegrated bone matrix of ZDSD rats had decreased mineral-to-matrix and increased crystallinity compared with SPD controls. Osseointegrated bone volume per total volume was not different between the groups, whereas implant fixation was significantly decreased in ZDSD at 2 weeks but not at 10 weeks. A combination of trabecular mineral apposition rate and postoperative MCP-1 levels explained 55.6% of the variance in osseointegration, whereas cortical thickness, osseointegration mineral apposition rate, and matrix compositional parameters explained 69.2% of the variance in implant fixation strength. The results support the growing recognition that both peri-implant structure and matrix composition affect implant fixation and suggest that postoperative inflammation may contribute to poor outcomes after TJR surgeries in T2DM patients. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Development of a Novel Circulating Autoantibody Biomarker Panel for the Identification of Patients with 'Actionable' Pulmonary Nodules.

Due to poor compliance and uptake of LDCT screening among high-risk populations, lung cancer is often diagnosed in advanced stages where treatment is rarely curative. Based upon the American College of Radiology's Lung Imaging and Reporting Data System (Lung-RADS) 80-90% of patients screened will have clinically "non-actionable" nodules (Lung-RADS 1 or 2), and those harboring larger, clinically "actionable" nodules (Lung-RADS 3 or 4) have a significantly greater risk of lung cancer. The development of a companion diagnostic method capable of identifying patients likely to have a clinically actionable nodule identified during LDCT is anticipated to improve accessibility and uptake of the paradigm and improve early detection rates. Using protein microarrays, we identified 501 circulating targets with differential immunoreactivities against cohorts characterized as possessing either actionable (n = 42) or non-actionable (n = 20) solid pulmonary nodules, per Lung-RADS guidelines. Quantitative assays were assembled on the Luminex platform for the 26 most promising targets. These assays were used to measure serum autoantibody levels in 841 patients, consisting of benign (BN; n = 101), early-stage non-small cell lung cancer (NSCLC; n = 245), other early-stage malignancies within the lung (n = 29), and individuals meeting United States Preventative Screening Task Force (USPSTF) screening inclusion criteria with both actionable (n = 87) and non-actionable radiologic findings (n = 379). These 841 patients were randomly split into three cohorts: Training, Validation 1, and Validation 2. Of the 26 candidate biomarkers tested, 17 differentiated patients with actionable nodules from those with non-actionable nodules. A random forest model consisting of six autoantibody (Annexin 2, DCD, MID1IP1, PNMA1, TAF10, ZNF696) biomarkers was developed to optimize our classification performance; it possessed a positive predictive value (PPV) of 61.4%/61.0% and negative predictive value (NPV) of 95.7%/83.9% against Validation cohorts 1 and 2, respectively. This panel may improve patient selection methods for lung cancer screening, serving to greatly reduce the futile screening rate while also improving accessibility to the paradigm for underserved populations.

Dynamic Monitoring of Seroconversion using a Multianalyte Immunobead Assay for Covid-19.

Multiplex technologies for interrogating multiple biomarkers in concert have existed for several decades; however, methods to evaluate multiple epitopes on the same analyte remain limited. This report describes the development and optimization of a multiplexed immunobead assay for serological testing of common immunoglobulin isotypes (e.g., IgA, IgM, and IgG) associated with an immune response to SARS-CoV-2 infection or vaccination. Assays were accomplished using a flow-based, multiplex fluorescent reader with dual-channel capability. Optimizations focused on analyte capture time, detection antibody concentration, and detection antibody incubation time. Analytical assay performance characteristics (e.g., assay range (including lower and upper limits of quantitation); and intra- and inter-assay precision) were established for either IgG/IgM or IgA/IgM serotype combination in tandem using the 'dual channel' mode. Analyte capture times of 30 min for IgG, 60 min for IgM, and 120 min for IgA were suitable for most applications, providing a balance of assay performance and throughput. Optimal detection antibody incubations at 4 µg/mL for 30 min was observed and are recommended for general applications, given the overall excellent precision (percent coefficient of variance (%CV) ≤ 20%) and sensitivity values observed. The dynamic range for the IgG isotype spanned several orders of magnitude for each assay (Spike S1, Nucleocapsid, and Membrane glycoproteins), which supports robust titer evaluations at a 1:500 dilution factor for clinical applications. Finally, the optimized protocol was applied to monitoring Spike S1 seroconversion for subjects (n = 4) that completed a SARS-CoV-2 vaccine regimen. Within this cohort, Spike S1 IgG levels were observed to reach maximum titers at 14 days following second dose administration, at a much higher (~40-fold) signal intensity than either IgM or IgA isotypes. Interestingly, we observed highly variable Spike S1 IgG titer decay rates that were largely subject-dependent were observed, which will be the topic of future studies.

Expression of Immunomodulatory Checkpoint Molecules in Drug-Resistant Neuroblastoma: An Exploratory Study.

Neuroblastoma is a common childhood cancer with poor prognosis when at its advanced stage. Checkpoint molecule inhibition is successful in treating multiple advanced adult cancers. We investigated PD-L1 and other checkpoint molecule expression to determine their roles in drug resistance and usefulness as targets for drug therapy. We developed three doxorubicin-resistant (DoxR) cell lines from parental cell lines. Matrigel in vitro invasion assays were used to compare invasiveness. Western blot assays were used to compare PD-L1 expression. Immuno-oncology checkpoint protein panels were used to compare concentrations of 17 checkpoint molecules both cellular and soluble. PD-L1 and 12 other checkpoint molecules were present in all cell lysates of each cell line without significantly different levels. Three were solubilized in the media of each cell line. PD-L1 is expressed in all DoxR and parental neuroblastoma cells and may be a potential target for drug therapy although its role in drug resistance remains unclear. Benchmarking checkpoint molecules provides the basis for future studies identifying targets for directed therapy and biomarkers for cancer detection or prognosis.

Bulk IgG glycosylation predicts COVID-19 severity and vaccine antibody response.

Although vaccination efforts have expanded, there are still gaps in our understanding surrounding the immune response to SARS-CoV-2. Measuring IgG Fc glycosylation provides insight into an infected individual's inflammatory state, among other functions. We set out to interrogate bulk IgG glycosylation changes from SARS-CoV-2 infection and vaccination, using plasma from mild or hospitalized COVID-19 patients, and from vaccinated individuals. Inflammatory glycans are elevated in hospitalized COVID-19 patients and increase over time, while mild patients have anti-inflammatory glycans that increase over time, including increased sialic acid correlating with RBD antibody levels. Vaccinated individuals with low RBD antibody levels and low neutralization have the same IgG glycan traits as hospitalized COVID-19 patients. In addition, a small vaccinated cohort reveals a decrease in inflammatory glycans associated with peak IgG concentrations and neutralization. This report characterizes the bulk IgG glycome associated with COVID-19 severity and vaccine responsiveness and can help guide future studies into SARS-CoV-2 protective immunity.

Expression of programmed death ligand 1 in drug-resistant osteosarcoma: An exploratory study.

BACKGROUND: Inhibition of the programmed death ligand 1, programmed death 1 pathway has been successfully used for treatment of multiple advanced adult cancers. However, its use in pediatric osteosarcoma is still in its infancy. In this study, we investigated programmed death ligand 1 and other checkpoint molecules' expression to determine the potential usefulness as targets for drug therapy. METHODS: We incubated human wild-type osteosarcoma cells with incremental concentrations of doxorubicin to create a doxorubicin-resistant cell line. Matrigel in vitro invasion assays were used to compare invasiveness. Comparative programmed death ligand 1 expression was evaluated by Western blot assays. An immuno-oncology checkpoint protein panel was used to compare concentrations of 16 other checkpoint molecules. Chi-square tests and Wilcoxon rank-sum tests were used to determine significant differences. RESULTS: A doxorubicin-resistant cell line was successfully created and was significantly more invasive than wild-type cells (0.47 vs 0.07, P < .001). On Western blot assay, doxorubicin-resistant but not wild-type cells expressed programmed death ligand 1. Doxorubicin-resistant cells had significantly higher levels of T-cell immunoglobulin-3 and cluster of differentiation 86 and higher cluster of differentiation 27, cluster of differentiation 40, lymphocyte-activation gene-3, cluster of differentiation 80, programmed death ligand 1, programmed death ligand 2, and inducible T-cell costimulatory expression than wild-type cells. Both lines expressed B- and T-lymphocyte attenuator, cluster of differentiation 28, herpesvirus entry mediator, and programmed death 1. Herpesvirus entry mediator, cluster of differentiation 40, and programmed death ligand 2 were also present in the culture media of both cell lines. CONCLUSION: Doxorubicin-resistant osteosarcoma seems to express higher programmed death ligand 1 than nonresistant wild-type cells. Benchmarking checkpoint molecules may provide the basis for future studies that elucidate pathways of drug resistance and tumor metastasis, biomarkers for cancer prognosis or recurrence, and future targets for directed drug therapy.

Relationship between circulating tumor-associated autoantibodies and clinical outcomes in advanced-stage NSCLC patients receiving PD-1/-L1 directed immune checkpoint inhibition.

BACKGROUND: Durable tumor regressions are observed in a subset of advanced-stage non-small cell lung cancer (NSCLC) patients receiving PD-1/-L1 targeted immune checkpoint inhibitors (or 'immunotherapy') alone or in combination with chemotherapy. However, the majority of advanced NSCLC patients receiving these agents do not experience long-term disease control. Existing methods to identify patients most likely to gain clinical benefit from PD-1/-L1 immunotherapy have limitations, creating a need for improved methods to guide treatment selection, particularly for those likely to benefit from single-agent immunotherapy. Here, we describe the development of a series of novel assays for tumor-associated autoantibodies as part of an exploratory study intended to determine if these biomarkers have potential prognostic value in this setting. METHOD: A selection of recombinant tumor autoantigens previously characterized for their diagnostic utility were developed and preliminarily evaluated by this study. These include: Fumarate Dehydrogenase (FH), Hydroxysteroid 17-Beta Dehydrogenase 10 (HSD17B10), Inosine Monophosphate Dehydrogenase 2 (IMPDH2), New York Esophageal Squamous Cell Carcinoma-1 (NY ESO-1), Phosphoglycerate Mutase 1 (PGAM1), and Vimentin. Custom Luminex immunobead assays were developed for these targets to quantitatively assess autoantibody levels in individual patient sera. Assays were erected as indirect immunoassays on MagPlex® Microspheres using standard carbodiimide/NHS-based chemistries, utilizing a biotin-conjugated secondary (i.e. anti-human IgG) antibody and R-phycoerythrin-conjugated streptavidin reporter system. Standard curves were created for quantitative purposes using commercially-available anti-antigen antibodies and permitted analytical performance characteristics to be calculated. These assays were used to preliminarily evaluate a series of pretreatment serum samples from stage IV NSCLC patients receiving anti PD-1/-L1 therapy after failure of at least one prior line of therapy (n = 40) and their classification efficiency calculated based on 12 months overall survival (OS) threshold. RESULTS: Six assays were developed that each showed dynamic ranges of four orders of magnitude and provided more than 90% classification accuracy based on the observed clinical outcome data. Inter- and intra-assay precision was assessed within these standards and overall %CVs of ≤7% and ≤ 10%, respectively, were calculated. Generally, the baseline level of autoantibodies were significantly (p < 0.05) lower in the ≥12 months survival group relative to the <12 months survival groups. Serum titers of FH, HSD170B, NY-ESO-1, and vimentin were significantly correlated with ≥12 month survival (p-value 0.0038, 0.0061, 0.0073, and 0.022, respectively). IMPDH2 and PGAM1 were found to have marginal significance (p-value 0.08 and 0.076, respectively). CONCLUSION: This study demonstrates an efficient and promising means for assessing circulating autoantibody titers that could be useful in selecting advanced NSCLC patients for PD-1/-L1 directed immunotherapy. Further exploration and validation of this paradigm is warranted to further refine current treatment selection methods for this therapeutic strategy.

Neutrophil-to-Lymphocyte Ratio Is a Predictive Biomarker in Patients with Epidermal Growth Factor Receptor (EGFR) Mutated Advanced Non-Small Cell Lung Cancer (NSCLC) Treated with Tyrosine Kinase Inhibitor (TKI) Therapy.

BACKGROUND: First-line treatment for patients with non-small cell lung cancer (NSCLC) with a sensitizing epidermal growth factor receptor (EGFR) mutation is a tyrosine kinase inhibitor (TKI). Despite higher response rates and prolonged progression free survival (PFS) compared with platinum doublet chemotherapy, a subset of these patients do not receive prolonged benefit from these agents. We investigate if the neutrophil-to-lymphocyte ratio (NLR) and other markers of cachexia and chronic inflammation correlate with worse outcomes in these patients. METHODS: This study is a retrospective review of 137 patients with advanced EGFR-mutated NSCLC treated with TKIs at Rush University Medical Center and University of Chicago Medicine from August 2011 to July 2019, with outcomes followed through July 2020. The predictive value of NLR and body mass index (BMI) was assessed at the start of therapy, and after 6 and 12 weeks of treatment by univariable and multivariable analyses. RESULTS: On univariable analysis, NLR ≥ 5 or higher NLR on a continuous scale were both associated with significantly worse PFS and overall survival (OS) at treatment initiation, and after 6 or 12 weeks of treatment. On multivariable analysis, NLR ≥ 5 was associated with increased risk of death at 12 weeks of therapy (HR 3.002, 95% CI 1.282-7.029, p = 0.011), as was higher NLR on a continuous scale (HR 1.231, 95% CI 1.063-1.425, p = 0.0054). There was no difference in PFS and OS and amongst BMI categories though number of disease sites and Eastern Cooperative Oncology Group (ECOG) performance status was associated with worse PFS and OS. CONCLUSIONS: Patients with NLR ≥ 5 have a worse median PFS and median OS than patients with NLR < 5. NLR may have value as a predictive biomarker and may be useful for selecting patients for therapy intensification in the front-line setting either at diagnosis or after 12 weeks on therapy. NLR needs to be validated prospectively.

Angiogenesis Biomarkers May Be Useful in the Management of Patients With Indeterminate Pulmonary Nodules.

BACKGROUND: Low-dose computed tomography (CT) lung cancer screening is known to have a high false positive rate. This study aims to survey biomarkers of angiogenesis for those capable of assigning clinical significance to indeterminate pulmonary nodules detected through CT imaging studies. METHODS: An institutional database and specimen repository was used to identify 193 patients with stage I non-small cell lung cancer (T1N0M0) and 110 patients with benign solitary pulmonary nodules detected by CT imaging studies. All specimens were evaluated in a blinded manner for 17 biomarkers of angiogenesis using multiplex immunoassays. Biomarker performance was calculated through the Mann-Whitney rank sum U test and a receiver operator characteristic analysis. These data were used to refine our previously reported multi-analyte classification panel, which was then externally validated against an independent patient cohort (n = 80). RESULTS: A total of 303 patients were screened for 17 biomarkers of angiogenesis. Median nodule size was 1.2 cm for benign cases and 1.8 cm for non-small cell lung cancer, whereas median smoking histories were 25 and 40 pack-years, respectively. Differences in serum concentrations of heparin-binding epidermal growth factor (HB-EGF), epidermal growth factor (EGF), vascular (V)EGF-A, VEGF-C, and VEGF-D were strongly significant (p ≤ 0.001) while follistatin, placental growth factor (PLGF), and bone morphogenic protein (BMP)-9 were significant (p ≤ 0.05) between patients with benign and malignant nodules. Our previously reported multi-analyte classification panel was refined to include interleukin (IL)-6, IL-10, IL-1 receptor antagonist (RA), tumor necrosis factor (TNF)-α, insulin-like growth factor binding protein (IGFBP)-5, IGFBP-4, IGF-2, stromal cell-derived factor (SDF)-1(α+ß), HB-EGF, and HGF resulting in improved accuracy and a validated negative predictive value of 96.4%. CONCLUSIONS: Angiogenesis biomarkers may be useful in discriminating stage I NSCLC from benign pulmonary nodules.