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The Eagle Bioscience’s MedFrontier Intact FGF23 Assay highlighted in a recent publication that focused on the determination of FGF23 Levels for the diagnosis of FGF23-mediated hypophosphatemia. Check out the full text and abstract below.

Abstract

Fibroblast growth factor-23 (FGF23) measurement is a critical tool in the evaluation of patients with disordered phosphate homeostasis. Available laboratory reference ranges for blood FGF23 were developed using samples from normophosphatemic individuals. Reliance on such values can lead to misdiagnosis in patients with FGF23-mediated hypophosphatemia, such as X-linked hypophosphatemia (XLH) and tumor-induced osteomalacia (TIO), in whom pathology-driving FGF23 levels can be in the “normal range.” To determine FGF23 levels that are diagnostic for the identification of patients with FGF23-mediated hypophosphatemic disorders, we studied 149 patients with various disorders of FGF23-mediated and FGF23-independent hypophosphatemia and defined cut-off levels for both intact FGF23 (iFGF23) and C-terminal FGF23 (cFGF23) that can accurately distinguish between FGF23-mediated and FGF23-independent hypophosphatemia. In addition, to demonstrate the relationship between FGF23 and phosphate across the spectrum of human physiology, we assessed blood levels of FGF23 and phosphate in 434 patients with various forms of hypophosphatemia, hyperphosphatemia, and normophosphatemia. An intact FGF23 cut point of 27 pg/mL was 100% sensitive and specific in distinguishing FGF23-mediated from FGF23-independent hypophosphatemia, and a cFGF23 cut point of 90 RU/mL was 100% sensitive and specific in distinguishing specifically TIO from FGF23-independent hypophosphatemia. There was overlap in the cFGF23 range of 45–90 RU/mL between genetic forms of FGF23 excess and FGF23-independent hypophosphatemia, substantiating the superiority of iFGF23 over cFGF23 in making the diagnosis of FGF23-mediated hypophosphatemia. In this cohort, using the laboratory upper limit of normal for cFGF23 (180 RU/mL) would result in a misdiagnosis in more than half of patients with FGF23-mediated hypophosphatemia. In this, the largest study of FGF23 in chronic hypophosphatemia to date, we established iFGF23 and cFGF23 cut-off values to assist in the evaluation and diagnosis of hypophosphatemic conditions. © 2022 American Society for Bone and Mineral Research (ASBMR). This article has been contributed to by US Government employees and their work is in the public domain in the USA.

Hartley, Iris R., et al. “Determination of FGF23 Levels for the Diagnosis of FGF23‐Mediated Hypophosphatemia.” Journal of Bone and Mineral Research, vol. 37, no. 11, 2022, pp. 2174–2185., https://doi.org/10.1002/jbmr.4702.

If you have any questions about the MedFrontier Intact FGF23 Assay or our other offerings, please contact us here.

The Eagle Bioscience’s BI-CAT Adrenaline & Noradrenaline ELISA was highlighted in a recent publication focusing matrix metalloproteinases and stress hormones in lung cancer progression. Check out the full text and abstract below.

Abstract

Several matrix metalloproteinases (MMPs) and psychological stress are associated with poor cancer prognosis. The current work goal was to determine MMPs’ and stress hormones’ blood concentrations from lung adenocarcinoma (LAC) patients. Patients were divided into the following groups: tobacco smokers (TS), wood smoke-exposed (W), passive smokers (PS), TS exposed to wood smoke (TW), and patients with no recognizable risk factor (N). MMPs, tissue inhibitors of metalloproteinases (TIMPs), adrenaline, noradrenaline, and cortisol blood concentrations were measured by ELISA. Zymography and Western blot assays were performed to determine MMP-2 and MMP-9 active and latent forms. MMP-2, MMP-3, MMP-9, and TIMP-1 blood concentrations, and MMP-9 gelatinase activity were augmented, while MMP-12, MMP-14, and TIMP-2 were diminished in LAC patients. Cortisol was increased in LAC samples. Adrenaline concentrations were higher in W, TS, and TW, and noradrenaline was increased in W and N groups. Positive correlations were observed among cortisol and TIMP-1 () and TIMP-2 () in the W group and between noradrenaline and MMP-2 () in the N group. MMPs’ blood concentration increments can be considered as lung cancer progression markers. Although stress hormones were also augmented, only weak correlations were observed between them and MMPs and TIMPs.

Gonzalez-Avila, Georgina, et al. “Matrix Metalloproteinases and Stress Hormones in Lung Cancer Progression.” Journal of Oncology, vol. 2022, 2022, pp. 1–13., https://doi.org/10.1155/2022/5349691.

If you have any questions about the BI-CAT Adrenaline & Noradrenaline ELISA or our other offerings, please contact us here.

The Eagle Bioscience’s Calprotectin ELISA Assay Kit was highlighted in a recent publication focusing on the determination of serum lactate and fecal calprotectin for assessing intestinal inflammation. Check out the full text and abstract below.

Abstract

Since past decades probiotics have been consistently reported to exhibit various health benefits. Probiotics are considered to stabilize the intestinal barrier and epithelial tight junction by modulating the immune functions and further hampering increased permeability disorder observed in inflammatory diseases. Several serological biomarkers such as serum lactate are utilized for determining the conditions of clinical sepsis and intestinal inflammation. Similarly, calprotectin which is also a abundant neutrophil protein found in fecal and plasma sample is responsible for elevating infectious and inflammatory conditions within the patients and rodents. The fecal calprotectin is also used for determining the underlying inflammatory response within the host upon probiotic administration. Both serum lactate and calprotectin serve as markers for the intestinal inflammation for assessing the safety of the probiotic use in the host. The main objective of this chapter is to provide the detailed experimental methods which can be considered while maintaining growth conditions and administration of probiotics within animal models and assessing the serum lactate and calprotectin levels through spectrophotometer, HPLC, and ELISA.

Shah, Firdosh, and Mitesh Kumar Dwivedi. “Determination of Serum Lactate and Fecal Calprotectin for Assessing the Intestinal Inflammation.” Methods and Protocols in Food Science, 2022, pp. 267–275., https://doi.org/10.1007/978-1-0716-2509-5_28.

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

The value of assay-ready cells in providing biologically relevant data for robust therapeutic development.

One of our suppliers, Svar Life Science, was recently featured in an editorial Select Science! This exclusive interview was with Dr. Peter Betz Wolff of the Analytical Development department at AGC Biologics. Dr. Wolff works to implement and develop a range of cell-based assays to meet specific client needs. He shares how his team recommends the use of assay-ready cells to provide the valuable biologically relevant data required for robust pharmaceutical development.

“Compared to non-cell-based approaches, the biggest advantage with cell-based systems is that they are a biologically relevant system, as they include data concerning internal signal cascades.” says Dr. Peter Betz Wolff. “This is of considerable interest to the authorities when reviewing potential new biologics coming to market.”

Check out the full article here.

iLite® Assay Ready Cells are developed by our partners at Svar Life Science. Their iLite technology is based upon a reporter gene assay format, modified and adapted for applications during the whole drug development cycle as well as for monitoring of biological drugs. These cell lines can be developed for any biopharmaceutical target and assays for drug potency, i.e. drug activity, and neutralizing antibodies (NAbs) can easily be set-up using the same cell line. The Assay Ready cells are genetically engineered to be used with a reporter gene assay technique for detection the the drug potency and the NAbs.

Check out our full portfolio of iLite Assay Ready Cells here.

The Eagle Bioscience’s Mouse Albumin ELISA Assay was utilized in a recent publication that focused on how REDD1 ablation attenuates the development of renal complications in diabetic mice. Check out the full text and abstract below.

Abstract

Chronic hyperglycemia contributes to development of diabetic kidney disease by promoting glomerular injury. In this study, we evaluated the hypothesis that hyperglycemic conditions promote expression of the stress response protein regulated in development and DNA damage response 1 (REDD1) in the kidney in a manner that contributes to the development of oxidative stress and renal injury. After 16 weeks of streptozotocin-induced diabetes, albuminuria and renal hypertrophy were observed in wild-type (WT) mice coincident with increased renal REDD1 expression. In contrast, diabetic REDD1 knockout (KO) mice did not exhibit impaired renal physiology. Histopathologic examination revealed that glomerular damage including mesangial expansion, matrix deposition, and podocytopenia in the kidneys of diabetic WT mice was reduced or absent in diabetic REDD1 KO mice. In cultured human podocytes, exposure to hyperglycemic conditions enhanced REDD1 expression, increased reactive oxygen species (ROS) levels, and promoted cell death. In both the kidney of diabetic mice and in podocyte cultures exposed to hyperglycemic conditions, REDD1 deletion reduced ROS and prevented podocyte loss. Benefits of REDD1 deletion were recapitulated by pharmacological GSK3β suppression, supporting a role for REDD1-dependent GSK3β activation in diabetes-induced oxidative stress and renal defects. The results support a role for REDD1 in diabetes-induced renal complications.

Sunilkumar, Siddharth, et al. “Redd1 Ablation Attenuates the Development of Renal Complications in Diabetic Mice.” 2022, https://doi.org/10.2337/figshare.20503266.v1.

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

The Eagle Bioscience’s Mouse PD-L1 ELISA Kit was highlighted in a recent publication that explored gene guided OX40L expression on tumor cells to initiate tumor “self-killing”. Check out the full text and abstract below.

Abstract

The low objective response rates and severe side effects largely limit the clinical outcomes of immune checkpoint blockade (ICB) therapy. Here, a tumor “self-killing” therapy based on gene-guided OX40L anchoring to tumor cell membrane was reported to boost ICB therapy. We developed a highly efficient delivery system HA/PEI-KT (HKT) to co-deliver the OX40L plasmids and unmethylated CG-enriched oligodeoxynucleotide (CpG). On the one hand, CpG induced the expression of OX40 on T cells within tumors. On the other hand, OX40L plasmids achieved the OX40L anchoring on the tumor cell membrane to next promote T cells responses via OX40/OX40L axis. Such synergistic tumor “self-killing” strategy finally turned “cold” tumors to “hot”, to sensitize tumors to programmed cell death protein 1/programmed cell death ligand 1 (PD-1/PD-L1) blockade therapy, and promoted an immune-mediated tumor regression in both B16F10 and 4T1 tumor models, with prevention of tumor recurrence and metastasis. To avoid the side effects, the gene-guided OX40L anchoring and PD-L1 silencing was proposed to replace the existing antibody therapy, which showed negligible toxicity in vivo. Our work provided a new possibility for tumor “self-killing” immunotherapy to treated various solid tumors.

Lin, Lin, et al. “Gene-Guided OX40L Anchoring to Tumor Cells for Synergetic Tumor ‘Self-Killing’ Immunotherapy.” Bioactive Materials, 2022, https://doi.org/10.1016/j.bioactmat.2022.07.008.

If you have any questions about the Mouse PD-L1 ELISA Kit or our other offerings, please contact us here.