Luminex xMAP Research Articles

Postnatal Dysregulation of Androgens in Extremely Preterm Male Infants.

Neurodevelopmental impairments are common among survivors of extremely preterm birth, particularly in males. Hyperactivation of the hypothalamic-pituitary-gonadal (HPG) axis has been suggested as an underlying cause, but this has been poorly investigated. Establish levels and temporal changes in circulating androgens in extremely preterm infant males. Observational cohort study analyzing cord blood serum (n = 25) and postnatal plasma (n = 13) collected from day 0 until week 11 from infant males born at 22.8-27.9 weeks gestational age. Testosterone and dihydrotestosterone (DHT) were determined using gas chromatography mass spectrometry, sex hormone-binding globulin (SHBG) with an enzyme-linked immunosorbent assay, and follicle-stimulating hormone (FSH) and luteinizing hormone (LH) with the Luminex xMAP multiplex assay. Testosterone and DHT levels were higher on day 0 (median 4.27 and 0.30 ng/mL) than in cord blood (0.15 and 0.01 ng/mL) (P < .001 for both). Levels of the hormones then declined rapidly until day 5 (median 0.16 and 0.12 ng/mL), then remained relatively constant throughout the study period. Median levels of testosterone and DHT across the whole study period were approximately 6-fold higher than reported in utero levels. FSH and LH showed similar postnatal patterns as the androgens. SHBG steadily increased over time, and, as a result, the fraction of bioavailable testosterone declined with infant postnatal age. The HPG axis is activated immediately after birth in extremely preterm infant males, resulting in an androgen pulse occurring several months earlier than during a normal pregnancy. The long-term implications of high androgen exposure during a sensitive neurodevelopmental period warrant further studies.

Multiple cytokine analysis of aqueous humor in uveitis with or without secondary glaucoma

To assess the level of both pro-inflammatory and anti-inflammatory cytokines in the aqueous humor (AH) of patients suffering from uveitis, with or without coexisting glaucoma, and compare them with patients diagnosed with primary open-angle glaucoma (POAG) and those with age-related cataract (ARC). By using Luminex xMAP® multiplex assays analyses, we assessed levels of 11 cytokines and chemokines, and compared them across groups, including uveitis-secondary glaucoma (USG) (n = 16), uveitis without glaucoma (UwoG), (n = 16), POAG (n = 16), and ARC (n = 16) to explore the correlation between these cytokines and the presence of uveitis, as well as intraocular pressure (IOP). Pro-inflammatory factors MCP-1, MIP-1β, IL-6, IL-8, and transforming growth factors TGF-β1 and TGF-β2 were significantly elevated in the AH of USG eyes. In the case of enhanced anti-inflammatory in the perioperative period, the pro-inflammatory factors remained notably elevated in the USG group compared to the UwoG group (P < 0.01). The levels of IL-6, IL-8, and MCP-1 in the AH of the USG group and POAG group had the same trend, which markedly surpassed those of the ARC group (P < 0.01). Significantly increased levels of MCP-1, MIP-1β, IL-6, IL-8, TGF-β1, and TGF-β2 were found in the AH of USG patients, implying a potential role for these mediators in the progression of glaucomatous manifestations within patients with uveitis. Besides the analysis revealed no discernible statistical disparity in cytokine concentrations within the AH of USG eyes whether the preoperative baseline IOP was greater than 30 mmHg or not, indicating that the safety of antiglaucoma surgery in USG patients even with baseline high IOP.

GET73 modulates lipopolysaccharide- and ethanol-induced increase in cytokine/chemokine levels in primary cultures of microglia of rat cerebral cortex.

- Alcohol-induced pro-inflammatory activation might influence cellular and synaptic pathology, thus contributing to the behavioral phenotypes associated with alcohol use disorders. In the present study, the possible anti-inflammatory properties of N-[(4-trifluoromethyl)-benzyl]4-methoxybutyramide (GET73), a promising therapeutic agent for alcohol use disorder treatment, were evaluated in primary cultures of rat cortical microglia. - Primary cultures of cerebral cortex microglial cells were treated with 100 ng/ml lipopolysaccharide (LPS; 8h, 37°C) or 75 mM ethanol (EtOH; 4 days, 37°C) alone or in the presence of GET73 (1-30 µM). At the end of the incubation period, multiparametric quantification of cytokines/chemokines was performed by using the xMAP technology and Luminex platform. Furthermore, cultured microglial cell viability following the treatment with EtOH and GET73, alone or in combination, has been measured by a colorimetric assay (i.e. MTT assay). - GET73 (10 and 30 µM) partially or fully prevented the LPS-induced increase of IL-6, IL-1β, RANTES/CCL5 protein and MCP-1/CCL2 levels. On the contrary, GET73 failed to attenuate the TNF-α level increase induced by LPS. Furthermore, GET73 treatment (10-30 µM) significantly attenuated or prevented the EtOH-induced increase of TNF-α, IL-6, IL-1β and MCP-1/CCL2 levels. Finally, at all the concentrations tested (1-30 µM), the GET73 treatment did not alter the EtOH-induced reduction of microglial cell viability. - The current results provide the first in vitro evidence of GET73 protective properties against EtOH-induced neuroinflammation. These data add more information on the complex and multifactorial profile of action of the compound, further supporting the significance of developing GET73 as a therapeutic tool for the treatment of individuals with alcohol use disorders.

Neuropsychiatric symptoms in cognitive decline and Alzheimer’s disease: biomarker discovery using plasma proteomics

Background and objectivesNeuropsychiatric symptoms (NPS) are common in older people with cognitive impairment and Alzheimer’s disease (AD). No biomarkers to detect the related pathology or predict the clinical evolution of...

Prevalence and genotype distribution of human papillomavirus infection among 66000 women from 2014 to 2023 in the plateau region of Southwest China

BackgroundPersistent infection with high-risk human papillomavirus (HR-HPV) plays a key role in the onset of cervical cancer. This study was designed to examine the epidemiological trends and genotype distribution of HPV from 2014 to 2023 in the plateau region of Southwest China.MethodsThe findings could offer valuable insights for clinical screening of cervical cancer and the formulation of HPV vaccination policies. This retrospective study analyzed 66,000 women who received HPV-DNA testing at the First People’s Hospital of Qujing, Yunnan, China, between 2014 and 2023. The cohort consisted of 33,512 outpatients, 3,816 inpatients, and 28,672 individuals undergoing health examinations. Cervical cells were collected for DNA extraction, and PCR amplification along with Luminex xMAP technology were used to detect 27 HPV genotypes. The data analysis was conducted using GraphPad Prism and IBM SPSS Statistics 27 software.ResultsThe overall HPV infection rate at the First People’s Hospital of Qujing declined from 24.92% in 2014 to 16.29% in 2023, averaging 16.02%. Specific infection rates were 18.50% among outpatients, 12.97% among inpatients, and 13.53% for health examination attendees. The predominant high-risk HPV genotypes identified were HPV52 (2.61%), HPV16 (2.06%), HPV58 (1.81%), HPV53 (1.55%), and HPV39 (1.09%). Meanwhile, the most frequent low-risk HPV genotypes were HPV6 (1.30%), HPV61 (1.21%), and HPV11 (0.85%). In HPV-positive cases, the distribution of single, double, triple, and quadruple or more infections were 79.90%, 15.17%, 3.59%, and 1.33%, respectively. The proportions of pure LR-HPV, pure HR-HPV, and mixed infections were 22.16%, 67.82%, and 10.02%, respectively. Age-specific analysis revealed a bimodal distribution of HPV infection, with the infection rate rapidly decreasing from 44.02% in the ≤ 19 age group to 19.55% in the 20–29 age group and 13.84% in the 30–39 age group, followed by a gradual increase to 14.64% in the 40–49 age group, 16.65% in the 50–59 age group, and 22.98% in the ≥ 60 age group. The coverage rates of the three available vaccines are all below 50%. The results of this study indicated a declining trend in HPV prevalence in the plateau region of Southwest China over the period from 2014 to 2023, especially in the reduction of genotypes targeted by vaccines.ConclusionThere were significant variations in the genotypes prevalent among different age groups, years, and patient sources within the same region. The underwhelming vaccination rates emphasize the critical need for developing either a multivalent vaccine or a personalized vaccine that targets the HPV genotypes common in the Chinese population. Furthermore, vaccinating adolescents to curb HPV infection and ensuring regular cervical cancer screenings for postmenopausal women are crucial steps.

Molecular circadian clock disruption in the leukocytes of individuals with type 2 diabetes and overweight, and its relationship with leukocyte–endothelial interactions

Aims/hypothesisAlterations in circadian rhythms increase the likelihood of developing type 2 diabetes and CVD. Circadian rhythms are controlled by several core clock genes, which are expressed in nearly every cell, including immune cells. Immune cells are key players in the pathophysiology of type 2 diabetes, and participate in the atherosclerotic process that underlies cardiovascular risk in these patients. The role of the core clock in the leukocytes of people with type 2 diabetes and the inflammatory process associated with it are unknown. We aimed to evaluate whether the molecular clock system is impaired in the leukocytes of type 2 diabetes patients and to explore the mechanism by which this alteration leads to an increased cardiovascular risk in this population.MethodsThis is an observational cross-sectional study performed in 25 participants with type 2 diabetes and 28 healthy control participants. Clinical and biochemical parameters were obtained. Peripheral blood leukocytes were isolated using magnetic bead technology. RNA and protein lysates were obtained to assess clock-related gene transcript and protein levels using real-time PCR and western blot, respectively. Luminex XMAP technology was used to assess levels of inflammatory markers. Leukocyte–endothelial interaction assays were performed by perfusing participants’ leukocytes or THP-1 cells (with/without CLK8) over a HUVEC monolayer in a parallel flow chamber using a dynamic adhesion system.ResultsParticipants with type 2 diabetes showed increased BMAL1 and NR1D1 mRNA levels and decreased protein levels of circadian locomotor output cycles kaput (CLOCK), cryptochrome 1 (CRY1), phosphorylated basic helix-loop-helix ARNT like 1 (p-BMAL1) and period circadian protein homologue 2 (PER2). Correlation studies revealed that these alterations in clock proteins were negatively associated with glucose, HbA1c, insulin and HOMA-IR levels and leukocyte cell counts. The leukocyte rolling velocity was reduced and rolling flux and adhesion were enhanced in individuals with type 2 diabetes compared with healthy participants. Interestingly, inhibition of CLOCK/BMAL1 activity in leukocytes using the CLOCK inhibitor CLK8 mimicked the effects of type 2 diabetes on leukocyte–endothelial interactions.Conclusions/interpretationOur study demonstrates alterations in the molecular clock system in leukocytes of individuals with type 2 diabetes, manifested in increased mRNA levels and decreased protein levels of the core clock machinery. These alterations correlated with the impaired metabolic and proinflammatory profile of the participants with type 2 diabetes. Our findings support a causal role for decreased CLOCK/BMAL1 activity in the increased level of leukocyte–endothelial interactions. Overall, our data suggest that alterations in core clock proteins accelerate the inflammatory process, which may ultimately precipitate the onset of CVD in patients with type 2 diabetes.Graphical

CX3CL1 release during immunogenic apoptosis is associated with enhanced anti-tumour immunity.

Immunogenic cell death (ICD) has emerged as a novel option for cancer immunotherapy. The key determinants of ICD encompass antigenicity (the presence of antigens) and adjuvanticity, which involves the release of damage-associated molecular patterns (DAMPs) and various cytokines and chemokines. CX3CL1, also known as neurotactin or fractalkine, is a chemokine involved in cellular signalling and immune cell interactions. CX3CL1 has been denoted as a "find me" signal that stimulates chemotaxis of immune cells towards dying cells, facilitating efferocytosis and antigen presentation. However, in the context of ICD, it is uncertain whether CX3CL1 is an important mediator of the effects of ICD. In this study, we investigated the intricate role of CX3CL1 in immunogenic apoptosis induced by mitoxantrone (MTX) in cancer cells. The Luminex xMAP technology was used to quantify murine cytokines, chemokines and growth factors to identify pivotal regulatory cytokines released by murine fibrosarcoma MCA205 and melanoma B16-F10 cells undergoing ICD. Moreover, a murine tumour prophylactic vaccination model was employed to analyse the effect of CX3CL1 on the activation of an adaptive immune response against MCA205 cells undergoing ICD. Furthermore, thorough analysis of the TCGA-SKCM public dataset from 98 melanoma patients revealed the role of CX3CL1 and its receptor CX3CR1 in melanoma patients. Our findings demonstrate enhanced CX3CL1 release from apoptotic MCA205 and B16-F10 cells (regardless of the cell type) but not if they are undergoing ferroptosis or accidental necrosis. Moreover, the addition of recombinant CX3CL1 to non-immunogenic doses of MTX-treated, apoptotically dying cancer cells in the murine prophylactic tumour vaccination model induced a robust immunogenic response, effectively increasing the survival of the mice. Furthermore, analysis of melanoma patient data revealed enhanced survival rates in individuals exhibiting elevated levels of CD8+ T cells expressing CX3CR1. These data collectively underscore the importance of the release of CX3CL1 in eliciting an immunogenic response against dying cancer cells and suggest that CX3CL1 may serve as a key switch in conferring immunogenicity to apoptosis.

Development of an algorithm combining blood-based biomarkers, fecal immunochemical test, and age for population-based colorectal cancer screening

Implementation of screening modalities have reduced the burden of colorectal cancer (CRC), but high false positive rates pose a major problem for colonoscopy capacity. We aimed to create a tailored screening algorithm that expands the fecal immunochemical test (FIT) with a blood specimen and current age to improve selection of individuals for diagnostic colonoscopy. In this prospective multi-center study, eight blood-based biomarkers (CEA, Ferritin, hsCRP, HE4, Cyfra21-1, Hepsin, IL-8 and OPG) were investigated in 1,977 FIT positive individuals from the Danish national CRC screening program undergoing follow-up colonoscopy. Specimens were analyzed on ARCHITECT i2000®, ARCHITECT c8000® or Luminex xMAP® machines. FIT analyses and blood-based biomarker data were combined with clinical data (i.e., age and colonoscopy findings) in a cross-validated logistic regression model (algorithm) benchmarked against a model solely using the FIT result (FIT model) applying different cutoffs for FIT positivity. The cohort included individuals with CRC (n = 240), adenomas (n = 938) or no neoplastic lesions (n = 799). The cross-validated algorithm combining the eight biomarkers, quantitative FIT result and age performed superior to the FIT model in discriminating CRC versus non-CRC individuals (AUC 0.77 versus 0.67, p < 0.001). When discriminating individuals with either CRC or high- or medium-risk adenomas versus low-risk adenomas or clean colorectum, the AUCs were 0.68 versus 0.64 for the algorithm and FIT model, respectively. The algorithm presented here can improve patient allocation to colonoscopy, reducing colonoscopy burden without compromising cancer and adenomas detection rates or vice versa.

A three-dimensional cell culture approach to investigate cytotoxic effects and production of inflammatory mediators by epoxy resin-based and calcium silicate-based endodontic sealer.

The aim of the present study was to assess the cytocompatibility of epoxy resin-based AH Plus Jet (Dentsply De Trey, Konstanz, Germany), Sealer Plus (MK Life, Porto Alegre, Brazil), calcium silicate-based Bio-C Sealer (Angelus, Londrina, PR, Brazil), Sealer Plus BC (MK Life) and AH Plus BC (Dentsply) through a tridimensional (3D) culture model of human osteoblast-like cells. Spheroids of MG-63 cells were produced and exposed to fresh root canal sealers extracts by 24h, and the cytotoxicity was assessed by the Lactate Dehydrogenase assay (LDH). The distribution of dead cells within the microtissue was assessed by fluorescence microscopy, and morphological effects were investigated by histological analysis. The secreted inflammatory mediators were detected in cell supernatants through flow luminometry (XMap Luminex). Cells incubated with AH Plus Jet, AH Plus BC, Sealer Plus BC and Bio-C Sealer extracts showed high rates of cell viability, while the Sealer Plus induced a significant reduction of cell viability, causing reduction on the spheroid structure. Sealer Plus and Seaker Plus BC caused alterations on 3D microtissue morphology. The AH Plus BC extract was associated with the downregulation of secretion of pro-inflammatory cytokines IL-5, IL-7, IP-10 and RANTES. The new AH Plus BC calcium silicate-based endodontic sealer did not reduce cell viability in vitro, while led to the downregulation of pro-inflammatory cytokines. Choosing the appropriate endodontic sealer is a crucial step. AH Plus BC demonstrated high cell viability and downregulation of pro-inflammatory cytokines, appearing reliable for clinical use, while Sealer Plus presented lower cytocompatibility.

Abstract A006: Bladder cancer risk stratification with the Oncuria 10 plex bead-based urinalysis assay using three different Luminex xMAP instrumentation platforms

Abstract Introduction and Objectives Oncuria® is a bead-based multiplex fluorescence immunoassay that coordinately measures 10 protein biomarkers in urine samples. The current study compared assay performance and output when urine samples were evaluated with the Oncuria assay using three different fluorescence-analyzing instruments commonly used in diagnostic laboratories worldwide. Methods We compared the performance of the clinically validated Oncuria bladder cancer (BC) multiplex immunoassay when data output was generated on three different analyzer systems. Voided urine samples from 36 subjects (18 with BC and 18 Controls) were reacted with Oncuria test reagents in three 96 well microtiter plates, and consecutively evaluated on the LED/image based MagPix, and laser/flow based Luminex 200 and FlexMap 3D (all xMAP instruments from Luminex Corp., Austin, TX). The BC assay uses magnetic bead based fluorescence technology (xMAP, Multi-analyte profiling; Luminex) to simultaneously quantify 10 protein analytes in urine specimens [i.e., angiogenin (ANG), apolipoprotein E (ApoE), carbonic anhydrase IX (CA9), CXCL8/interleukin-8 (IL-8), matrix metalloproteinase-9 (MMP-9), matrix metalloproteinase-10 (MMP-10), serpin A1/alpha-1 anti-trypsin (A1AT), serpin E1/plasminogen activator inhibitor-1 (PAI-1), CD138/syndecan-1 (SDC1), and vascular endothelial growth factor-A (VEGF-A)]. Results All three platforms categorized all 10 analytes in identical samples at nearly identical concentrations, with variance across systems typically &amp;lt;5%. While the most contemporary instrument, the FlexMap 3D, output higher raw fluorescence values than the two comparator systems, standard curve slopes and analyte concentrations determined in urine samples were concordant across all three units. Forty-four percent of BC samples registered ≥1 analyte above the highest standard concentration, i.e., A1AT (n=7/18), IL-8 (n=5), and/or ANG (n=2). In Controls, A1AT was higher in one sample. Conclusions In conclusion, the Oncuria BC assay performed similarly well across three different flow analysis platforms for all 10 analytes simultaneously evaluated in urine samples. This agreement across instruments indicates that the test is amenable to standardized performance in laboratories using existing xMAP, without requiring costly outlays for new equipment. Citation Format: Toru Sakatani, Sunao Tanaka, Kaoru Murakami, Richard Waldron, Wayne Hogrefe, Charles Rosser, Hideki Furuya. Bladder cancer risk stratification with the Oncuria 10 plex bead-based urinalysis assay using three different Luminex xMAP instrumentation platforms [abstract]. In: Proceedings of the AACR Special Conference on Bladder Cancer: Transforming the Field; 2024 May 17-20; Charlotte, NC. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(10_Suppl):Abstract nr A006.

GDNF and miRNA-29a as biomarkers in the first episode of psychosis: uncovering associations with psychosocial factors.

Schizophrenia involves complex interactions between biological and environmental factors, including childhood trauma, cognitive impairments, and premorbid adjustment. Predicting its severity and progression remains challenging. Biomarkers like glial cell line-derived neurotrophic factor (GDNF) and miRNA-29a may bridge biological and environmental aspects. The goal was to explore the connections between miRNAs and neural proteins and cognitive functioning, childhood trauma, and premorbid adjustment in the first episode of psychosis (FEP). This study included 19 FEP patients who underwent clinical evaluation with: the Childhood Trauma Questionnaire (CTQ), the Premorbid Adjustment Scale (PAS), the Positive and Negative Syndrome Scale (PANSS), and the Montreal Cognitive Assessment Scale (MoCA). Multiplex assays for plasma proteins were conducted with Luminex xMAP technology. Additionally, miRNA levels were quantitatively determined through RNA extraction, cDNA synthesis, and RT-qPCR on a 7500 Fast Real-Time PCR System. Among miRNAs, only miR-29a-3p exhibited a significant correlation with PAS-C scores (r = -0.513, p = 0.025) and cognitive improvement (r = -0.505, p = 0.033). Among the analyzed proteins, only GDNF showed correlations with MoCA scores at the baseline and after 3 months (r = 0.533, p = 0.0189 and r = 0.598, p = 0.007), cognitive improvement (r = 0.511, p = 0.025), and CTQ subtests. MIF concentrations correlated with the PAS-C subscale (r = -0.5670, p = 0.011). GDNF and miR-29a-3p are promising as biomarkers for understanding and addressing cognitive deficits in psychosis. This study links miRNA and MIF to premorbid adjustment and reveals GDNF's unique role in connection with childhood trauma.

ShinyMBA: a novel R shiny application for quality control of the multiplex bead assay for serosurveillance studies

The multiplex bead assay (MBA) based on Luminex xMAP technology can be used as a tool to measure seroprevalence as part of population immunity evaluations to multiple antigens in large-scale serosurveys. However, multiplexing several antigens presents challenges for quality control (QC) assessments of the data because multiple parameters must be evaluated for each antigen. MBA QC parameters include monitoring bead counts and median fluorescence intensity (MFI) for each antigen in plate wells, and performance of assay controls included on each plate. Analyzing these large datasets to identify plates failing QC standards presents challenges for many laboratories. We developed a novel R Shiny application, shinyMBA, to expedite the MBA QC processes and reduce the risk of user error. The app allows users to rapidly merge multi-plate assay outputs to evaluate bead count, MFI, and performance of assay controls using statistical process control charts for all antigen targets simultaneously. The utility of the shinyMBA application and its various outputs are demonstrated using data from 32 synthetic xPONENT files with 3 multiplex antigens and two population serosurveillance studies that evaluated 1200 and 3871 samples, respectively, for 20 multiplexed antigens. The shinyMBA open-source code is available for download and modification at https://github.com/CDCgov/shinyMBA. Incorporation of shinyMBA into Luminex serosurveillance workflows can vastly improve the speed and accuracy of QC processes.

Abstract 7631: Protein Plus BCT: A novel blood collection tube for stabilizing plasma proteins of interest in ambient whole blood storage

Abstract Introduction: Many of the soluble plasma proteins (e.g., cytokines) that are crucial for cancer diagnosis, prognosis, and prediction of cancer immunotherapy outcomes are found in blood cells such as platelets and leukocytes. During blood collection and sample storage, ex vivo platelet activation, hemolysis, and blood cell degradation can occur, which causes the release of blood cell-secreted proteins into the plasma. The contamination of these proteins may confound true in vivo levels of plasma proteins of interest, resulting in inaccurate or inconsistent assay results. Protein Plus BCT is a new blood collection tube that maintains accurate plasma protein levels during ambient whole blood storage. Methods: Blood samples from self-proclaimed healthy donors were drawn into Protein Plus BCT, EDTA, and ACD-A tubes. All the samples were stored at ambient temperature for up to 5 days. Plasma was isolated using a general double-spin protocol and frozen at -80 °C until use. Plasma levels of protein biomarkers were measured by Ella Simple Plex Assays (Bio-Techne) and Luminex xMAP® Technology Assays (Bio-Techne, samples tested by LuminexPLORE Lab) following manufacturers’ dilution and processing recommendations. Results: Over 50 key plasma proteins like cytokines, cancer, and immuno-oncology checkpoint markers in samples collected into Protein Plus BCT were analyzed by immunoassays and compared side-by-side to those collected in EDTA and ACD-A tubes. EDTA and ACD-A samples exhibited a substantial elevation in the plasma concentration of many, such as IL-8, IL-1β, HGF, VEGF, MMP-9, CCL5/RANTES and TGF-β1 post draw, indicating platelet activation and blood cell degradation during ambient temperature storage. Samples collected into Protein Plus BCT displayed limited ex vivo platelet activation and minimal contamination by blood cell-secreted proteins, maintaining the draw-time plasma levels of proteins of interest for up to 5 days in whole blood at ambient temperature. Conclusions: The novel Protein Plus BCT maintains draw-time plasma protein levels during extended whole blood storage at room temperature by limiting ex vivo platelet activation, hemolysis, and blood cell degradation. Protein Plus BCT ensures sample integrity and minimizes preanalytical variables, providing cancer researchers and clinical assay developers greater flexibility in sample handling and improved confidence in downstream plasma protein analysis. Protein Plus BCT is for Research Use Only. Not for use in diagnostic procedures. Citation Format: Jing Li, Nicholas M. George, Sama Mehta, Jordan LaRue, Eunju Seong, Nursen Binbuga, Rachel Miller, Karl Bisselou. Protein Plus BCT: A novel blood collection tube for stabilizing plasma proteins of interest in ambient whole blood storage [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7631.

Abstract 3773: Bladder cancer risk stratification with the Oncuria 10 plex bead-based urinalysis assay using three different Luminex xMAP instrumentation platforms

Abstract Introduction and Objectives: Oncuria® is a bead-based multiplex fluorescence immunoassay that coordinately measures 10 protein biomarkers in urine samples. The current study compared assay performance and output when urine samples were evaluated with the Oncuria assay using three different fluorescence-analyzing instruments commonly used in diagnostic laboratories worldwide. Methods: We compared the performance of the clinically validated Oncuria bladder cancer (BC) multiplex immunoassay when data output was generated on three different analyzer systems. Voided urine samples from 36 subjects (18 with BC and 18 Controls) were reacted with Oncuria test reagents in three 96 well microtiter plates, and consecutively evaluated on the LED/image based MagPix, and laser/flow based Luminex 200 and FlexMap 3D (all xMAP instruments from Luminex Corp., Austin, TX). The BC assay uses magnetic bead based fluorescence technology (xMAP, Multi-analyte profiling; Luminex) to simultaneously quantify 10 protein analytes in urine specimens [i.e., angiogenin (ANG), apolipoprotein E (ApoE), carbonic anhydrase IX (CA9), CXCL8/interleukin-8 (IL-8), matrix metalloproteinase-9 (MMP-9), matrix metalloproteinase-10 (MMP-10), serpin A1/alpha-1 anti-trypsin (A1AT), serpin E1/plasminogen activator inhibitor-1 (PAI-1), CD138/syndecan-1 (SDC1), and vascular endothelial growth factor-A (VEGF-A)]. Results: All three platforms categorized all 10 analytes in identical samples at nearly identical concentrations, with variance across systems typically &amp;lt;5%. While the most contemporary instrument, the FlexMap 3D, output higher raw fluorescence values than the two comparator systems, standard curve slopes and analyte concentrations determined in urine samples were concordant across all three units. Forty-four percent of BC samples registered ≥1 analyte above the highest standard concentration, i.e., A1AT (n=7/18), IL-8 (n=5), and/or ANG (n=2). In Controls, A1AT was higher in one sample. Conclusions: In conclusion, the Oncuria BC assay performed similarly well across three different flow analysis platforms for all 10 analytes simultaneously evaluated in urine samples. This agreement across instruments indicates that the test is amenable to standardized performance in laboratories using existing xMAP, without requiring costly outlays for new equipment. Citation Format: Sunao Tanaka, Toru Sakatani, Kaoru Murakami, Richard T. Waldron, Walter Morales, Wayne Hogrefe, Charles J. Rosser, Hideki Furuya. Bladder cancer risk stratification with the Oncuria 10 plex bead-based urinalysis assay using three different Luminex xMAP instrumentation platforms [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3773.

Abstract 6642: Exploring the x-ray psoralen activated cancer therapy mechanism of action in a genetically engineered mouse model of soft tissue sarcoma

Abstract BACKGROUND: Psoralen is a natural ultraviolet activated compound that has been used for over 70 years to treat skin cancer, psoriasis, and vitiligo. Recently, to expand its use beyond external treatment, a novel therapeutic called X-PACT (X-ray psoralen activated cancer therapy) was created to treat internal tumors. A combination of 8-methoxypsoralen and phosphors that convert low doses of x-ray radiation to ultraviolet (UV) light are injected into solid tumors and subsequently activated by x-ray photons with considerable antineoplastic effect. Notably, canine clinical trials have observed significant abscopal effects of X-PACT therapy on metastatic lesions throughout patients, but the immunomodulatory mechanisms of action are unclear (Nolan et al, in submission). Here, we present preliminary data investigating the immune response to X-PACT therapy in a murine soft tissue sarcoma (STS) model. METHODS: Six mice of the inducible KrasG12D/+; p53flox/flox (KP) murine STS model with palpable, gastrocnemius tumors were used in this initial study. Four mice underwent treatment with X-PACT. In this group, psoralen was mixed with energy converters and injected into the tumor. The mice then received low-level radiation to activate the drug. Treatment was performed five times over a 15-day period and the animals were sacrificed within 48 hours of final treatment. The other two mice with induced tumors received no treatment prior to sacrifice. For both groups, a cardiac blood draw was performed at the time of sacrifice to obtain plasma serum for analysis. Luminex xMAP technology was used for multiplexed quantification of 45 mouse cytokines, chemokines and growth factors. RESULTS: There were five markers that showed significantly different levels between the treated and control groups. Results indicated significantly higher (p = 0.006) plasma concentrations of macrophage derived chemokine (MDC) following five rounds of treatment with X-PACT therapy. Additionally, the treated mice displayed significantly lower concentrations of granulocyte colony-stimulating factor (G-CSF, p = 0.003), eotaxin (p = 0.016), tissue inhibitor of matrix metalloproteinase 1 (TIMP1, p = 0.024), and interleukin-1β (IL-1β, p = 0.033) compared to untreated mice with STS. CONCLUSION: In humans, MDC levels are associated with longer survival and lower cancer severity. G-CSF, eotaxin, TIMP1, and IL-1β are upregulated in cancer patients and correlate with disease severity. Together, the lower concentrations of G-CSF, Eotaxin, TIMP1, and IL-1β suggest a softening of cancer severity following X-PACT treatment. Further studies and larger sample sizes are necessary to confirm and expand upon these preliminary findings. Citation Format: Beatrice Schleupner, Alexandra Hunter Aitchison, Elle MacAlpine, Nicole Cantor, Jason Somarelli, Brian Brigman, Julia Visgauss, Michael Monument, William Eward. Exploring the x-ray psoralen activated cancer therapy mechanism of action in a genetically engineered mouse model of soft tissue sarcoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6642.

Exploring cell-free assays for COVID-19 serosurvey

Serosurveys to monitor immunity toward COVID-19 in the population are primarily performed using an ELISA to screen samples for SARS-CoV-2 antibodies, followed by confirmation by a virus neutralization test, which is considered the Gold Standard. However, virus neutralization test may not be feasible for some laboratories because of the requirement for specific facilities and trained personnel. In an attempt to address this limitation, we evaluated three cell-free methods as potential alternatives for assessing SARS-CoV-2 seroprevalence in human population from plasma. We report the establishment of two inhibition ELISAs designed to detect anti-Spike RBD IgG antibodies and a microsphere quantitative suspension array technology assay, based on the Luminex xMAP platform, to measure the presence of antibodies against various SARS-CoV-2 antigens, including anti-RBD. These methods were also compared to a commercial chemiluminescent immunoassay designed for anti-RBD antibodies detection and to the combined ELISA + virus neutralization test strategy. These cell-free assays performed equally to estimate the percentage of positive and negative samples and could be used to determine the prevalence of SARS-CoV-2 antibodies in human population, at least in cohort with high-expected prevalence, without the use of seroneutralization assay.

Antigen-specific chemokine profiles as biomarkers for detecting Mycobacterium tuberculosis infection.

Latent tuberculosis (TB) infection can progress to active TB, which perpetuates community transmission that undermines global TB control efforts. Clinically, interferon-γ release assays (IGRAs) are commonly used for active TB case detection. However, low IGRA sensitivity rates lead to false-negative results for a high proportion of active TB cases, thus highlighting IGRA ineffectiveness in differentiating MTB-infected individuals from healthy individuals. Participants enrolled at Beijing Chest Hospital from May 2020-April 2022 were assigned to healthy control (HC), LTBI, IGRA-positive TB, and IGRA-negative TB groups. Screening cohort MTB antigen-specific blood plasma chemokine concentrations were measured using Luminex xMAP assays then were verified via testing of validation cohort samples. A total of 302 individuals meeting study inclusion criteria were assigned to screening and validation cohorts. Testing revealed significant differences in blood plasma levels of CXCL9, CXCL10, CXCL16, CXCL21, CCL1, CCL19, CCL27, TNF-α, and IL-4 between IGRA-negative TB and HC groups. Levels of CXCL9, CXCL10, IL-2, and CCL8 biomarkers were predictive for active TB, as reflected by AUC values of ≥0.9. CXCL9-based enzyme-linked immunosorbent assay sensitivity and specificity rates were 95.9% (95%CI: 91.7-98.3) and 100.0% (92.7-100.0), respectively. Statistically similar AUC values were obtained for CXCL9 and CXCL9-CXCL10 assays, thus demonstrating that combined analysis of CXCL10 and CXCL9 levels did not improve active TB diagnostic performance. The MTB antigen stimulation-based CXCL9 assay may compensate for low IGRA diagnostic accuracy when used to diagnose IGRA-negative active TB cases and thus is an accurate and sensitive alternative to IGRAs for detecting MTB infection.

Sex-related differences in serum biomarker levels predict the activity and efficacy of immune checkpoint inhibitors in advanced melanoma and non-small cell lung cancer patients

BackgroundImmune Checkpoint Inhibitors (ICIs) lead to durable response and a significant increase in long-term survival in patients with advanced malignant melanoma (MM) and Non-Small Cell Lung Cancer (NSCLC). The identification of serum cytokines that can predict their activity and efficacy, and their sex interaction, could improve treatment personalization.MethodsIn this prospective study, we enrolled immunotherapy-naïve patients affected by advanced MM and NSCLC treated with ICIs. The primary endpoint was to dissect the potential sex correlations between serum cytokines (IL-1β, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, GM-CSF, MCP-1, TNF-ɑ, IP-10, VEGF, sPD-L1) and the objective response rate (ORR). Secondly, we analyzed biomarker changes during treatment related to ORR, disease control rate (DCR), progression free survival (PFS) and overall survival (OS). Blood samples, collected at baseline and during treatment until disease progression (PD) or up to 2 years, were analyzed using Luminex xMAP or ELLA technologies.ResultsSerum samples from 161 patients (98 males/63 females; 92 MM/69 NSCLC) were analyzed for treatment response. At baseline, IL-6 was significantly lower in females (F) versus males (M); lower levels of IL-4 in F and of IL-6 in both sexes significantly correlated with a better ORR, while higher IL-4 and TNF-ɑ values were predictive of a lower ORR in F versus M. One hundred and sixty-five patients were evaluable for survival analysis: at multiple Cox regression, an increased risk of PD was observed in F with higher baseline values of IL-4, sPD-L1 and IL-10, while higher IL-6 was a negative predictor in males. In males, higher levels of GM-CSF predict a longer survival, whereas higher IL-1β predicts a shorter survival. Regardless of sex, high baseline IL-8 values were associated with an increased risk of both PD and death, and high IL-6 levels only with shorter OS.ConclusionsSerum IL-1β, IL-4, IL-6, IL-10, GM-CSF, TNF-ɑ, and sPD-L1 had a significant sex-related predictive impact on ORR, PFS and OS in melanoma and NSCLC patients treated with ICIs. These results will potentially pave the way for new ICI combinations, designed according to baseline and early changes of these cytokines and stratified by sex.

Cecropin A: investigation of a host defense peptide with multifaceted immunomodulatory activity in a chicken hepatic cell culture.

Host defense peptides (HDPs) are increasingly referred to as promising candidates for the reduction of the use of conventional antibiotics, thereby combating antibiotic resistance. As HDPs have been described to exert various immunomodulatory effects, cecropin A (CecA) appears to be a potent agent to influence the host inflammatory response. In the present study, a chicken primary hepatocyte-non-parenchymal cell co-culture was used to investigate the putative immunomodulatory effects of CecA alone and in inflammatory conditions evoked by polyinosinic-polycytidylic acid (Poly I:C). To examine the viability of the cells, the extracellular lactate dehydrogenase (LDH) activity was determined by colorimetric assay. Inflammatory markers interleukin (IL)-8 and transforming growth factor-ß1 (TGF-ß1) were investigated using the ELISA method, whereas concentrations of IL-6, IL-10, and interferon-γ (IFN-γ) were assayed by Luminex xMAP technology. Extracellular H2O2 and malondialdehyde levels were measured by fluorometric and colorimetric methods, respectively. Results of the lower concentrations suggested the safe application of CecA; however, it might contribute to hepatic cell membrane damage at its higher concentrations. We also found that the peptide alleviated the inflammatory response, reflected by the decreased production of the pro-inflammatory IL-6, IL-8, and IFN-γ. In addition, CecA diminished the levels of anti-inflammatory IL-10 and TGF-ß1. The oxidative markers measured remained unchanged in most cases of CecA exposure. CecA displayed a multifaceted immunomodulatory but not purely anti-inflammatory activity on the hepatic cells, and might be suggested to maintain the hepatic inflammatory homeostasis in Poly I:C-triggered immune response. To conclude, our study suggests that CecA might be a promising molecule for the development of new immunomodulatory antibiotic-substitutive agents in poultry medicine; however, there is still a lot to clarify regarding its cellular effects.

Modulation of secretory factors by lipofundin contributes to its anti‑neuroinflammatory effects.

As the global population ages, the prevalence of neuroinflammatory diseases such as Alzheimer's disease, Parkinson's disease and stroke continues to increase. Therefore, it is necessary to develop preventive and therapeutic methods against neuroinflammatory diseases. Lipofundin is a lipid emulsion commonly used in clinical anesthetic solvents and nutritional supplements. Lipid emulsions have been shown to possess anti-inflammatory properties. However, the potential beneficial effect of lipofundin against neuroinflammation requires elucidation. In the present study, two cell models were used to investigate the efficacy of lipofundin against neuroinflammation. In the first model, BV2 mouse microglial cells were treated with lipopolysaccharide (LPS) to induce nitric oxide (NO) production as a model of neuroinflammation. In the second model, HMC3 human microglial were activated by LPS, and changes in the secretion of factors associated with inflammation were analyzed using Luminex xMAP® technology. Griess assay results revealed that lipofundin significantly prevented and treated LPS-induced NO production. An anti-neuroinflammatory effect was also observed in HMC3 cells, where lipofundin exhibited excellent preventive and therapeutic properties by reducing the LPS-induced expression and secretion of interleukin-1β. Notably, lipofundin also promoted the secretion of certain growth factors, suggesting a potential neuroprotective effect. These results demonstrate that, in addition to its role as a solvent for drugs and nutritional support, lipofundin may also have beneficial effects in alleviating the progression of neuroinflammation. These findings may serve as an important reference for future translational medicine applications.