Dopamine Sensitive ELISA Assay Utilized in Recent Publication
The Eagle Bioscience’s Calprotectin ELISA Assay Kit was utilized in a recent publication that explored intestinal microbiome and metabolome signatures in patients with chronic granulomatous disease. Check out the full text and abstract below!


Background

Chronic granulomatous disease (CGD) is caused by defects in any 1 of the 6 subunits forming the nicotinamide adenine dinucleotide phosphate oxidase complex 2 (NOX2), leading to severely reduced or absent phagocyte-derived reactive oxygen species production. Almost 50% of patients with CGD have inflammatory bowel disease (CGD-IBD). While conventional IBD therapies can treat CGD-IBD, their benefits must be weighed against the risk of infection. Understanding the impact of NOX2 defects on the intestinal microbiota may lead to the identification of novel CGD-IBD treatments.

Objective

We sought to identify microbiome and metabolome signatures that can distinguish individuals with CGD and CGD-IBD.

Methods

We conducted a cross-sectional observational study of 79 patients with CGD, 8 pathogenic variant carriers, and 19 healthy controls followed at the National Institutes of Health Clinical Center. We profiled the intestinal microbiome (amplicon sequencing) and stool metabolome, and validated our findings in a second cohort of 36 patients with CGD recruited through the Primary Immune Deficiency Treatment Consortium.

Results

We identified distinct intestinal microbiome and metabolome profiles in patients with CGD compared to healthy individuals. We observed enrichment for Erysipelatoclostridium spp, Sellimonas spp, and Lachnoclostridium spp in CGD stool samples. Despite differences in bacterial alpha and beta diversity between the 2 cohorts, several taxa correlated significantly between both cohorts. We further demonstrated that patients with CGD-IBD have a distinct microbiome and metabolome profile compared to patients without CGD-IBD.

Conclusion

Intestinal microbiome and metabolome signatures distinguished patients with CGD and CGD-IBD, and identified potential biomarkers and therapeutic targets.

Chandrasekaran, Prabha, et al. “Intestinal microbiome and metabolome signatures in patients with chronic granulomatous disease.” Journal of Allergy and Clinical Immunology, 2023.


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Dopamine Sensitive ELISA Assay Utilized in Recent Publication

The Eagle Bioscience’s Serotonin ELISA Assay was utilized in a recent publication that explored the modification of the serotonergic systems and phenotypes by gestational micronutrients. Check out the full text and abstract below.


Abstract

Micronutrients consumed in excess or imbalanced amounts during pregnancy may increase the risk of metabolic diseases in offspring, but the mechanisms underlying these effects are unknown. Serotonin (5-hydroxytryptamine, 5-HT), a multifunctional indoleamine in the brain and the gut, may have key roles in regulating metabolism. We investigated the effects of gestational micronutrient intakes on the central and peripheral serotonergic systems as modulators of the offspring’s metabolic phenotypes. Pregnant Wistar rats were fed an AIN-93G diet with 1-fold recommended vitamins (RV), high 10-fold multivitamins (HV), high 10-fold folic acid with recommended choline (HFolRC), or high 10-fold folic acid with no choline (HFolNC). Male and female offspring were weaned to a high-fat RV diet for 12 weeks. We assessed the central function using the 5-HT2C receptor agonist, 1-(3-chlorophenyl)piperazine (mCPP), and found that male offspring from the HV- or HFolRC-fed dams were less responsive (P < 0.05) whereas female HFolRC offspring were more responsive to mCPP (P < 0.01) at 6 weeks post-weaning. Male and female offspring from the HV and HFolNC groups, and male HFolRC offspring had greater food intake (males P < 0.001; females P < 0.001) and weight gain (males P < 0.0001; females P < 0.0001), elevated colon 5-HT (males P< 0.01; females P < 0.001) and fasting glucose concentrations (males P < 0.01; females P < 0.01), as well as body composition toward obesity (males P < 0.01; females P < 0.01) at 12 weeks post-weaning. Colon 5-HT was correlated with fasting glucose concentrations (males R2=0.78, P < 0.0001; females R2=0.71, P < 0.0001). Overall, the serotonergic systems are sensitive to the composition of gestational micronutrients, with alterations consistent with metabolic disturbances in offspring.

Chen, Vicki, et al. “Modification of the Serotonergic Systems and Phenotypes by Gestational Micronutrients.” Journal of Endocrinology, vol. 257, no. 2, 2023, https://doi.org/10.1530/joe-22-0305.


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FluoBolt- KLOTHO Fluorescence Immunoassay

High Sensitivity; Single Step Immunoassay for α-KLOTHO in Human Serum and Plasma

Eagle Biosciences is excited to highlight the FloBolt- KLOTHO Fluorescence Immunoassay from Fianostics! This assay detects only α-KLOTHO and does not cross-react with β-KLOTHO. No interference of recombinant FGF-23 with the assay’s signal up to a 100-fold molar excess was monitored. Check out the assay background and highlights below!


Background

α-KLOTHO is expressed in kidney, small intestine, placenta and prostate. The soluble peptide can be found in serum and cerebrospinal fluid. It may play a role in the calcium/ phosphorus homeostasis regulation by e.g. inhibiting active vitamin D synthesis. Further, it is also known as an antiaging-hormone by extending life span by inhibiting insulin/ IGF1 signaling pathway, as experiments in mice showed. KLOTHO is a co-receptor of fibroblast growth factor 23 (FGF-23). Research has investigated association of altered serum KLOTHO levels with chronic kidney disease and failure, renal and hepatocellular carcinomas, osteoporosis or cardiovascular diseases.

α-KLOTHO can be found either as a membrane bound or a secreted form. The membrane bound form consists of 1012 amino acids (aa), starting with a 56 aa long signaling sequence and followed by two glycosyl hydrolase 1 regions (position 57-506 and 515-953). Both glycosyl hydrolase 1 regions lack one essential Glu active site residue. Thus, it is inactive in vivo as a glycosidase although it belongs to the glycosyl hydrolase 1 family. KLOTHO’s secreted isoform, which predominates over the membrane bound form, consists of 549 amino acids (aa). It is produced by alternative splicing and differs from the membrane bound form by aa 550 to 1012 missing.


FluoBolt- KLOTHO Fluorescence Immunoassay Highlights

  • High Sensitivity
  • Single Step Procedure
  • No Washing Steps
  • No Enzyme Substrate required
  • Long Term Stable Signal

If you have any questions about this kit or any of our other offerings, contact us here.

Dopamine Sensitive ELISA Assay Utilized in Recent Publication

The Eagle Bioscience’s Cortisol Saliva ELISA was highlighted in a recent publication that focused on peripheral brain-derived neurotrophic factor (BDNF) and salivary cortisol levels in college students with different levels of academic stress. Check out the full text and abstract below!


Abstract

Introduction

Brain-derived neurotrophic factor (BDNF) is essential for brain physiological processes influencing memory and learning. BDNF levels can be affected by many factors, including stress. Stress increase serum and salivary cortisol levels. Academic stress is of the chronic type. BDNF levels can be measure from serum, plasma or platelets, and there is still no standard methodology, which is relevant to ensure reproducibility and comparability between studies.

Hypothesis

(i) BDNF concentrations in serum show greater variability than in plasma. (ii) In college students with academic stress, peripheral BDNF decreases and salivary cortisol increases.

General Objective

To standardize plasma and serum collection for BDNF levels and to determine whether academic stress affects peripheral BDNF and salivary cortisol levels.

Castillo-Navarrete, Juan-Luis, et al. “Peripheral Brain-Derived Neurotrophic Factor (BDNF) and Salivary Cortisol Levels in College Students with Different Levels of Academic Stress. Study Protocol.” PLOS ONE, vol. 18, no. 2, 2023.


If you have any questions about the Cortisol Saliva ELISA or our other offerings, please contact us here.

Dopamine Sensitive ELISA Assay Utilized in Recent Publication

The Eagle Bioscience’s Total FGF-21 ELISA Assay was highlighted in a recent publication that focused on increased fibrosis in white adipose tissue. Check out the full text and abstract below.


Abstract

Fibrosis is a pathological state caused by excess deposition of extracellular matrix proteins in a tissue. Male bovine growth hormone (bGH) transgenic mice experience metabolic dysfunction with a marked decrease in lifespan and with increased fibrosis in several tissues including white adipose tissue (WAT), which is more pronounced in the subcutaneous (Sc) depot. The current study expanded on these initial findings to evaluate WAT fibrosis in female bGH mice and the role of transforming growth factor (TGF)-β in the development of WAT fibrosis. Our findings established that female bGH mice, like males, experience a depot-dependent increase in WAT fibrosis, and bGH mice of both sexes have elevated circulating levels of several markers of collagen turnover. Using various methods, TGF-β signaling was found unchanged or decreased—as opposed to an expected increase—despite the marked fibrosis in WAT of bGH mice. However, acute GH treatments in vivo, in vitro, or ex vivo did elicit a modest increase in TGF-β signaling in some experimental systems. Finally, single nucleus RNA sequencing confirmed no perturbation in TGF-β or its receptor gene expression in any WAT cell subpopulations of Sc bGH WAT; however, a striking increase in B lymphocyte infiltration in bGH WAT was observed. Overall, these data suggest that bGH WAT fibrosis is independent of the action of TGF-β and reveals an intriguing shift in immune cells in bGH WAT that should be further explored considering the increasing importance of B cell–mediated WAT fibrosis and pathology.

Bell, Stephen, et al. “Increased Fibrosis in White Adipose Tissue of Male and Female BGH Transgenic Mice Appears Independent of TGF-β Action.” Endocrinology, vol. 164, no. 5, 2023.


If you have any questions about our Total FGF-21 ELISA Assay or our other offerings, please contact us here.

Dopamine Sensitive ELISA Assay Utilized in Recent Publication

The Eagle Bioscience’s Ferritin ELISA Assay was highlighted in a recent publication that focused on the examination of functional properties, protein quality, and iron bioavailability of low-phytate in pea protein ingredients. Check out the full text and abstract below.


Abstract

The effect of seed phytate content (regular and low) on the composition (protein and mineral content), protein quality [in vitro protein digestibility-corrected amino acid score (IVPDCAAS)], iron bioavailability, and functionality (solubility, oil/water holding capacity, foaming capacity and stability, and emulsion stability) of pea flours and extracted protein isolates was investigated. There was 37–45% less phytate in the flours of the low-phytate varieties compared to the regular varieties and approximately 39% less for the isolates. Upon extraction of protein, phytate increased over threefold, but for the mineral ions, this was selective in that Fe2+ ions increased more than threefold, while Ca2+ content halved. The phytate content did not influence the IVPDCAAS of the flours or isolates. The functional properties of the isolates and flours were largely similar between the low and regular phytate varieties. For each variety, iron was more bioavailable in the flours (10.5–22.0 ng ferritin/mg protein) than in the isolates (2.9–16.5 ng/mg). The low-phytate flours (20.6 ng/mg) had overall higher iron bioavailability than the regular phytate pea flours (10.7 ng/mg). For the isolates, this trend was not significant, possibly due to high intra-variety variation and the limited number of samples; however, the mean iron bioavailability value of the three low-phytate isolates was three times greater than that of the two regular phytate isolates. In conclusion, protein isolates extracted from low-phytate varieties did not show deleterious or positive impacts on the functional characteristics or protein quality; more evidence is required for iron bioavailability.

Chigwedere, C.M., Stone, A., Konieczny, D. et al. Examination of the functional properties, protein quality, and iron bioavailability of low-phytate pea protein ingredients. Eur Food Res Technol (2023).


If you have any questions about our Ferritin ELISA Assay or our other offerings, please contact us here.

Dopamine Sensitive ELISA Assay Utilized in Recent Publication

The Eagle Bioscience’s Anti-dsDNA ELISA Assay was utilized in a recent publication that focused on anti-double stranded DNA antibodies. Check out the full text and abstract below.


Abstract

This work reports the first amperometric biosensor for the simultaneous determination of the single or total content of the most relevant human immunoglobulin isotypes (hIgs) of anti-dsDNA antibodies, dsDNA-hIgG, dsDNA-hIgM, dsDNA-hIgA and dsDNA-three hIgs, which are considered relevant biomarkers in prevalent autoimmune diseases such as systemic lupus erythematosus (SLE) as well as of interest in neurodegenerative diseases such as Alzheimer’s disease (AD). The bioplatform involves the use of neutravidin-functionalized magnetic microparticles (NA-MBs) modified with a laboratory-prepared biotinylated human double-stranded DNA (b-dsDNA) for the efficient capture of specific autoantibodies that are enzymatically labeled with horseradish peroxidase (HRP) enzyme using specific secondary antibodies for each isotype or a mixture of secondary antibodies for the total content of the three isotypes. Transduction was performed by amperometry (−0.20 V vs. the Ag pseudo-reference electrode) using the H2O2/hydroquinone (HQ) system after trapping the resulting magnetic bioconjugates on each of the four working electrodes of a disposable quadruple transduction platform (SP4CEs). The bioplatform demonstrated attractive operational characteristics for clinical application and was employed to determine the individual or total hIgs classes in serum from healthy individuals and from patients diagnosed with SLE and AD. The target concentrations in AD patients are provided for the first time in this work. In addition, the results for SLE patients and control individuals agree with those obtained by applying ELISA tests as well as with the clinical ranges reported by other authors, using individual detection methodologies restricted to centralized settings or clinical laboratories.

Arévalo, Beatriz, et al. “Anti-Double Stranded DNA Antibodies: Electrochemical Isotyping in Autoimmune and Neurological Diseases.” Analytica Chimica Acta, vol. 1257, 2023, p. 341153.


If you have any questions about our Anti-dsDNA ELISA Assay or our other offerings, please contact us here.

Dopamine Sensitive ELISA Assay Utilized in Recent Publication

The Eagle Bioscience’s Serotonin Sensitive ELISA Kit was highlighted in a recent publication that focused on dietary tryptophan deficiency. Check out the full text and abstract below.


Abstract

Micronutrient deficiency is a major cause of disease throughout the world. Yet, how perturbations influence the immune-microbiome interface remains poorly understood. Here, we report that loss of dietary tryptophan (Trp) reshapes intestinal microbial communities, including the depletion of probiotic L. reuteri, drives tran- scriptional changes to immune response genes in the intestinal ileum, and reshapes the regulatory T cell (Treg) compartment. Dietary Trp deficiency promotes expansion of RORgt+ Treg cells and the loss of Gata3+ Tregs in a microbiota-dependent manner. In the absence of dietary Trp, provision of the AhR ligand indole-3-carbinol is sufficient to restore the Treg compartment. Together, these data show that dietary Trp deficiency perturbs the interaction between the host and its bacterial symbionts to regulate Treg homeosta- sis via the deprivation of bacterially derived Trp metabolites. Our findings highlight an essential role for im- mune-microbiome crosstalk as a key homeostatic regulator during nutrient deficiency.

Rankin, Lucille C., et al. “Dietary Tryptophan Deficiency Promotes Gut Rorγt+ Treg Cells at the Expense of GATA3+ Treg Cells and Alters Commensal Microbiota Metabolism.” Cell Reports, vol. 42, no. 3, 2023, p. 112135.


If you have any questions about the Serotonin Sensitive ELISA Kit or our other offerings, please contact us here.

The Eagle Bioscience’s Calprotectin ELISA Assay was utilized in a recent publication that explored how fecal keratin 8 is a noninvasive and specific marker for intestinal injury. Check out the full text and abstract below!


Abstract

Specific biomarkers of intestinal injury associated with necrotizing enterocolitis (NEC) are needed to diagnose and monitor intestinal mucosal injury and recovery. This study aims to develop and test a modified enzyme-linked immunosorbent assay (ELISA) protocol to detect the total keratin 8 (K8) in the stool of newborns with NEC and investigate the clinical value of fecal K8 as a marker of intestinal injury specifically associated with NEC. We collected fecal samples from five newborns with NEC and five gestational age-matched premature neonates without NEC at the Lucile Packard Children’s Hospital Stanford and Washington University School of Medicine, respectively. Fecal K8 levels were measured using a modified ELISA protocol and Western blot, and fecal calprotectin was measured using a commercial ELISA kit. Clinical data, including gestational age, birth weight, Bell stage for NEC, feeding strategies, total white blood cell (WBC) count, and other pertinent clinical variables, were collected and analyzed. Fecal K8 levels were significantly higher in the pre-NEC group (1–2 days before diagnosis of NEC) and NEC group than those in the non-NEC group. Moreover, fecal K8 was relatively higher at the onset of NEC and declined after the resolution of the disease. Results with similar trends to fecal K8 were also seen in fecal calprotectin, but not seen in total WBC count. In conclusion, a modified ELISA protocol for the total K8 protein was successfully developed for the detection of fecal K8 in the clinical setting of premature newborns with NEC. Fecal K8 is noted to be significantly increased in premature newborns with NEC and may, therefore, serve as a noninvasive and specific marker for intestinal epithelial injury associated with NEC.

Wang, Kewei, et al. “Fecal Keratin 8 Is a Noninvasive and Specific Marker for Intestinal Injury in Necrotizing Enterocolitis.” Journal of Immunology Research, vol. 2023, 2023, pp. 1–8.


If you have any questions about our Calprotectin ELISA Assay or any of our other offerings, contact us here.

Dopamine Sensitive ELISA Assay Utilized in Recent Publication

The Eagle Bioscience’s Histamine ELISA Assay was highlighted in a recent publication that explored how exocytic machineries differentially control mediator release from allergen-triggered RBL-2H3 cells. Check out the full text and abstract below.


Background

Mast cells utilize SNAREs (soluble-N-ethyl-maleimide sensitive factor attachment protein receptors) and SM (Sec1/Munc18) proteins to secrete/exocytose a variety of proinflammatory mediators. However, whether a common SNARE-SM machinery is responsible remains unclear.

Methods

Four vesicle/granule-anchored SNAREs (VAMP2, VAMP3, VAMP7, and VAMP8) and two Munc18 homologs (Munc18a and Munc18b) were systematically knocked down or knocked out in RBL-2H3 mast cells and antigen-induced release of β-hexosaminidase, histamine, serotonin, and TNF was examined. Phenotypes were validated by rescue experiments. Immunofluorescence studies were performed to determine the subcellular distribution of key players.

Results

The reduction of VAMP8 expression inhibited the exocytosis of β-hexosaminidase, histamine, and serotonin but not TNF. Unexpectedly, however, confocal microscopy revealed substantial co-localization between VAMP8 and TNF, and between TNF and serotonin. Meanwhile, the depletion of other VAMPs, including knockout of VAMP3, had no impact on the release of any of the mediators examined. On the other hand, TNF exocytosis was diminished specifically in stable Munc18bknockdown cells, in a fashion that was rescued by exogenous, RNAi-resistant Munc18b. In line with this, TNF was co-localized with Munc18b (47%) to a much greater extent than with Munc18a (13%).

Conclusion

Distinct exocytic pathways exist in mast cells for the release of different mediators.

Adhikari, P., Ayo, T.E., Vines, J.C. et al. Exocytic machineries differentially control mediator release from allergen-triggered RBL-2H3 cells. Inflamm. Res. 72, 639–649 (2023).


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