Sclerostin Biomarker Spotlight

A recent systemic review and meta-analysis of studies with serum amyloid A in patients with COVID-19 published by the International Journal of Infectious Diseases has found high concentrations of serum amyloid A associated with higher COVID-19 severity and mortality. This review analyzed nineteen studies consisting of over five thousand patients with COVID-19. The pooled results showed that serum amyloid A concentrations were significantly higher in those patients with severe disease and non-survivors. This measurement could be useful for risk stratification and clinical monitoring of these patients.


A state of excessive local and systemic inflammation and immune activation are strongly associated with oxidative stress, coagulation abnormalities, and multi-organ dysfunction in patients with coronavirus disease 2019 (COVID-19). While safe and effective vaccines have been developed and are currently being rolled out, effective therapies to mitigate the clinical manifestations of COVID-19, e.g., repurposed antiviral and immunosuppressant agents, remain limited. In this context, the use of biomarkers of disease severity and clinical progression would facilitate the early identification of patients requiring aggressive management and monitoring and assist with the judicious use of healthcare resources. Given the key pathophysiological role of inflammation and immunity in the clinical progress of COVID-19, markers that reflect the activation of these pathways might be particularly useful for risk stratification and effective management.

Serum amyloid A (SAA) genes and proteins are significantly activated during the acute phase response, which comprises a number of phenomena that occur in the presence of inflammation and infection, e.g., increased temperature and hormonal and metabolic alterations. Circulating SAA concentrations, typically low under physiological circumstances (20–50 mg/l), can increase up to 1000-fold within the first 24–48 h of an acute phase response. This is the consequence of increased synthesis in the liver that is triggered by several stimuli, including tumor necrosis factor (TNF), interleukin (IL)-1β, IL-6, and interferon gamma (IFN-γ). SAA, in turn, can activate the complement system and the nucleotide-binding domain leucine-rich repeat-containing family pyrin-domain containing 3 (NLRP3) inflammasome, further increase the synthesis of TNF, IL-1β, and IL-6, and activate other proinflammatory cytokines such as IL-1α and IL-23. Notably, these mediators have been shown to contribute significantly to the onset of the cytokine storm and its adverse clinical consequences in COVID-19. Therefore, it is plausible that the acute increase in SAA concentrations in patients with COVID-19 might not only reflect the presence of an acute phase response, but also herald the development of a cytokine storm and, consequently, multi-organ failure and an increased risk of adverse outcomes.

Two systematic reviews and meta-analyses on a relatively limited number of studies, three and five, respectively, have reported a significant and positive association between SAA concentrations and COVID-19 severity. Following the publication of several additional studies, an updated systematic review and meta-analysis was conducted of the available evidence on the clinical implications of SAA concentrations in patients with COVID-19.

Read the full text here.

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Human SAA ELISA Assay Kit
Human TNF Alpha ELISA Assay
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If you have any questions about our products contacts us here.

Lipid Peroxidase Assay Kit Publication Spotlight

Eagle Biosciences Lipid Peroxidase Assay Kit was recently highlighted in two studies involving hepatic ischemia and reperfusion injuries. Hepatic ischemia is a condition where the liver does not recieve enough blood or oxygen, causing the liver cells injury. Lipid peroxidation is a well-established mechanism of cellular injury, and is used as an indicator of oxidative stress in cells and tissues. Lipid peroxides are unstable and decompose to form a complex series of compounds including reactive carbonyl compounds. Polyunsaturated fatty acid peroxides generate malondialdehyde (MDA) and 4-hydroxyalkenals (HAE) upon decomposition. The measurement of these biomolecules has been used as a indicator of lipid peroxidase.

The Eagle Biosciences’ Lipid Peroxidase Assay Kit is a highly sensitive tool for measuring MDA and HAE in biological fluids.

Read more about these studies below:

Gendy A, Elnagar MR, Soubh A, et al. Morin Alleviates Hepatic Ischemia/Reperfusion-Induced Mischief: In Vivo and In Silico Contribution of Nrf2, TLR4, and NLRP3. Biomed Pharmacother. 2021;138:111539.

Mohamed DZ, El-Sisi AE, Sokar SS, et al. Targeting Autophagy to Modulate Hepatic Ischemia/Reperfusion Injury: A Comparative Study Between Octreotide and Melatonin as Autophagy Modulators Through AMPK/PI3k/AKT/mTOR/ULK1 and Keap1/Nrf2 Signaling Pathways in Rats. Eur J Pharmacol. 2021;897:173920.

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Lipid Peroxidase Assay Kit
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Eagle Biosciences Announces Agreement with Genetic Analysis

Eagle Biosciences Announces Agreement with
Genetic Analysis AS for Distribution in North America

Eagle Biosciences, Inc., a North American distributor of assay kits and antibodies, recently announced a distribution agreement with Genetic Analysis AS, a Norwegian molecular diagnostics company. The focus of the collaboration is on the unique, patented GA-map® Dysbiosis Test which detects and characterizes imbalance in the gut microbiota (dysbiosis) in human fecal samples. Additionally, Genetic Analysis has developed a fecal COVID-19 test that is performed on the same GA-map platform and is an important research tool in the analysis of an individual’s COVID-19 status.

Genetic Analysis (GA) is a molecular diagnostics company with a core focus of providing innovative tools for studying the human microbiome. GA has developed and launched the GA-map platform for routine gut microbiome research and analysis. The first test on this groundbreaking platform is the GA-map Dysbiosis Test. The Dysbiosis Test is the first documented test to identify and characterize the gut microbiota composition. The GA-map Test platform is not based on sequencing but is a targeted probe-based assay. The precise and targeted approach makes it an easy plug and play platform as long as the targets are identified. GA’s vision is to become the company that standardizes gut microbiota testing worldwide.

“We are looking forward to working with Genetic Analysis and the opportunity to bring their products to labs in the US and Canada.”, states Eagle Biosciences President Dan Keefe. “Genetic Analysis has been a pioneer in the microbiota industry and has over ten years of experience in the field. We are especially excited about their GA-map® Dysbiosis Test because it is the first standardized, off-the-shelf biome mapping kit and can be run in any PCR lab.”

If you have any questions about the GA-map® test platform or any of Eagle Biosciences products, please contact us here.

About Genetic Analysis AS

Genetic Analysis AS (GA) is a science-based diagnostic company and pioneer in the human microbiome field with more than 10 years of expertise in research and product development. The unique GA-map® platform is based on a pre-targeted multiplex approach specialized for simultaneous analysis of a large number of bacteria in one reaction. The test results are generated by utilizing the clinically validated cutting edge GA-map® software algorithm. This enables immediate results without the need of further bioinformatics work. GA’s mission is to become the leading company for standardized gut microbiota testing worldwide, and GA is committed to help unlocking and restoring the human microbiome through its state-of-the-art technology. GA holds 22 highly qualified employees with relevant scientific backgrounds and with competence in bioinformatics, molecular biology, and bioengineering.

For more information about Genetic Analysis, click here.

About Eagle Biosciences, Inc.

Since 2010, Eagle Biosciences has been providing the highest quality and best value immunoassays, antibodies, and proteins available on the market. There are many suppliers of ELISAs and other assays and hundreds of thousands of products to choose from, but EagleBio only offers products that deliver the maximum level of performance and provide reliable and trusted results.

For more information about Eagle Biosciences, Inc., click here.

Sclerostin Biomarker Spotlight
Sclerostin is a secreted glycoprotein that functions as a potent inhibitor of Wnt signaling. It acts by binding to the Wnt-coreceptor LRP5/6 thus inhibiting bone formation by regulating osteoblast function and promoting osteoblast apoptosis. Sclerostin is primarily produced by osteocytes. It inhibits the canonical Wnt pathway and thereby osteoblasts. It also stimulates RANKL release by the osteocytes and thereby osteoclast recruitment. Inhibition of sclerostin causes stimulation of bone formation and inhibition of resorption. Read more about sclerostin’s role in bone remodeling here.

Sclerostin levels are altered in response to hormonal stimuli or due to pathophysiological conditions. The concentrations are increased in disorders such as hypoparathyroidism, Paget’s disease, multiple myeloma and in cancer induced bone diseases. Mutations in the SOST gene can cause sclerosteosis and van Buchem disease which are bone dysplasia disorders characterized by progressive skeletal overgrowth. Sclerostin levels are decreased in primary hyperparathyroidism, as well as by the mechanical stimulation of bone.

A mini-review was published in the The Journal of Clinical Endocrinology & Metabolism regarding the effect of sclerostin inhibition on the cardiovascular safety of patients. Read the full text here.

Eagle Biosciences offers a sensitive and reliable assay for the detection of sclerostin in serum and plasma samples.

Advantages of the Sclerostin ELISA Assay Kit

    • High Quality – rigorously validated according to ICH/FDA/EMEA guidelines
    • Low Sample Volume – only 20ul of sample per well
    • Easy – ready to use protocol, standards and controls included

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Osteoprotegerin ELISA Assay Kit
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If you are looking for any other specific related products, or have any questions about our offerings contact us here.

IL-6 High Sensitive ELISA Assay Kit New Product

Eagle Biosciences is excited to announce the Human IL-6 High Sensitive ELISA Assay Kit from Biomedica! This powerful kit offers a wide dynamic range with extraordinary sensitivity. It provides superior performance and reliability for all your researching needs.

About Interleukin-6 (IL-6)

IL-6 is a pleiotropic cytokine that plays a crucial role in regulating the acute phase response, inflammation, hematopoiesis, glucose metabolism, bone metabolism, and cancer progression. IL-6 is an early marker of acute inflammation. In patients with COVID-19, IL-6 levels are significantly elevated and associated with adverse clinical outcomes. Therefore, serum IL-6 is an important biomarker for severity of COVID-19 and has great potential for guiding treatment of the disease.

IL-6 can reliably be measured by ELISA ( BI-IL6) in human serum, plasma and urine samples with Biomedica’s fully validated assay kit. The kit is highly sensitive and offers a wide dynamic range. The kit incorporates ready to use standards and controls.

Features & Benefits of the Human IL-6 High Sensitive ELISA Assay Kit

√ EASY ready to use calibrators & controls included
√ High SENSITIVITY measurable values in serum and plasma
√ Full validation package – the assay is optimized for clinical samples

Related publications:

Interleukin-6 in Covid-19: A systematic review and meta-analysis. Coomes EA, Haghbayan H. Rev Med Virol. 2020 Nov;30(6):1-9. Full text.

Assessing the importance of interleukin-6 in COVID-19. Chen LYC, Hoiland RL, Stukas S, Wellington CL, Sekhon MS. Lancet Respir Med. 2021 Feb;9(2):e13. Full text.

If you have any questions about the Human Il-6 High Sensitive ELISA Assay Kit or any of our other offerings, contact us here.

ELISA for Detecting SARS-CoV-2 Mutant Strains

SARS-CoV-2, a single stranded RNA virus, has quickly become the subject of much research worldwide. Coronaviruses are composed of four primary proteins: the spike (S), envelope (E), membrane (M), and nucleocapsid (N). The spike protein (S-protein) performs two primary tasks that aid in host infection: 1) mediates the attachment between the virus and host cell surface receptors such as ACE2, and 2) facilitates viral entry into the host cell by assisting in the fusion of the viral and host cell membranes. In December of 2020 three new SARS-CoV-2 variants came to light, UK B.1.1.7, South Africa B.1.351 and Brazil P.1/P.2.

Eagle Biosciences offers a SARS CoV-2 Spike Protein Antigen Quantitative ELISA Assay Kit that is highly sensitive. Clinical studies show that this kit is effective at detecting the spike protein antigen in all three major circulating SARS-CoV-2 variant strains. Click here to learn more.

About the SARS-CoV-2 Spike Protein Antigen Quantitative ELISA Assay Kit

  • Validated for both serum and plasma samples.
  • No cross-reactivity with other respiratory pathogens.
  • Standardization and reproducibility, with lot-to-lot consistency.

Eagle Biosciences is dedicated to providing support to researchers in their studies of SAR-CoV-2 and the new variants. To hear more about our COVID-19 resources and other offerings, contact us here.

25-OH Vitamin D Kits Publication Spotlight

Eagle Biosciences’ Mouse/Rat 25-OH Vitamin D ELISA Assay Kit and 25-OH Vitamin D ELISA Assay Kit were recently utilized in two different publications. One study was looking into the mechanism of how vitamin D can help to protect the liver against non-alcoholic fatty lipid disease (NAFLD) in those with Type 2 diabetes. The other study was focused on how taking α-glucosidase inhibitors (α-GI) with a meal can affect the postprandial bone turnover in overweight or obese individuals.

Learn more about these studies and to read the full text, follow the citations below.

Lim H, Lee H, Lim Y. Effect of Vitamin D3 Supplementaion on Hepatic Lipid Dysregulation Associated with Autophagy Regulatory AMPK/Akt-mTOR Signaling in Type 2 Diabetic Mice. Exp Biol Med. 2021. Full text.

Kreitman A, Schneider SH, Hao L, et al. Reduced Postprandial Bone Resorption and Greater Rise in GLP-1 in Overweight and Obese Individuals After an Alpha-Glucosidase Inhibitor: a Double-Blinded Randomized Crossover Trial. Osteoporos Int. 2021. Full text.

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25-OH Vitamin D HPLC Assay Kit
25-OH Vitamin D HPLC Column

If you are looking for any other specific related products, or have any questions about the rest of our offerings contact us here. To view our extensive collection of other Vitamin ELISA Assay Kits click here.

RANKL and RANK Biomarker Spotlight

Receptor activator of nuclear factor kappa B ligand, RANKL, and its specific receptor RANK, are members of the tumor necrosis factor (TNF) family and are the main stimulatory factor for the formation of mature osteoclasts and are essential for their survival. The major source of RANKL are osteocytes, former osteoblasts that become embedded within the mineralized bone matrix. RANKL and its specific receptor RANK are not only key regulators of bone remodeling but also play an essential role in immunobiology, e.g. lymph node formation, establishment of the thymic microenvironment, mammary gland development during pregnancy, bone metastasis in cancer and sex-hormone, progestin-driven breast cancer, thermoregulation, and finally in the development of type 2 diabetes mellitus.

A recent study has uncovered a new role for RANKL and RANK in bone remodeling. Researchers have found that extracellular vesicles containing RANKL and RANK may have an important role in the long range signaling for bone remodeling. These signaling molecules have the potential to be targeted for therapeutics and also used diagnostically.

Click here to learn more.

Holliday LS, Patel SS, Rody WJ. RANKL and RANK in Extracellular Vesicles: Surprising New Players in Bone Remodeling. Extracell Vesicles Circ Nucleic Acids. 2021; 2:18-28.

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Free Soluble RANKL ELISA Assay Kit
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Polystreptavidin R Product Announcement

Eagle Biosciences announces new Polystreptavidin R (Polystrept R) Extraordinary high Biotin binding capacity! This reagent is for surface coating of plastics, membranes, beads and etc. with maximum biotin binding capacity. It improves the signal-noise-relation and saves material costs.

About Streptavidin

Streptavidin is a tetrameric protein (4 x 13 kDa), which binds very tightly to the small molecule Biotin. The binding constant for this interaction is extremely high (Ka ~ 1013 M-1) and turns the Streptavidin/Biotin system into a basis of many biochemical applications. Streptavidin-coated surfaces are characterized by very low nonspecific bindings. Streptavidin coating of solid phases offers a universal immobilization principle for the detection and analysis of proteins, peptides, PCR-fragments etc.

About Polystreptavidin R

Polystreptavidin R is characterized by a immensely high biotin binding capacity in combination with robustness against thermal and chemical influences. Polystreptavidin R is easy to use and suitable for coatings on membranes, beads, microplates, biochips and other plastic materials.

Polystreptavidin R at the strip test (lateral flow assay)

Polystreptavidin R shows outstanding properties when coated on nitrocellulose membranes. The very high biotin binding capacity and the very low washout effects provide a significant signal enhancement at the test line. Highly efficient immobilization of biotinylated molecules and low non-specific binding provide a high signal-to-noise ratio. Polystreptavidin R is a liquid concentrate and can be easily diluted with a neutral buffer for coating or spotting and dried at room temperature without any further production steps. If required, stabilizers can also be added. At temperatures of 2°C to 50°C Polystreptavidin R is stable for at least 24 months and supports a long shelf life.

Why use streptavidin-coated microplates and Polystrept R with lateral flow test strips?

  • Convenient method for a uniform and stable immobilization of biotinylated molecules
  • Immobilization of Biomolecules on solid phases in a directed manner, while avoiding or minimizing denaturation
  • Ready-to-use, no washing or blocking steps required
  • High signal-to-noise ratio
  • Low nonspecific binding
  • Long shelf life
  • Lower reagent consumption and especially enormous cost savings with lateral flow test stripes

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Ultra-Sensitive Streptavidin Coated Clear 96 Well Microplate
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If you have any questions about Polystreptavidin R or our other offerings, contact us here.


Eagle Biosciences’ COVID-19 IgM and IgG ELISA Assay Kits were recently highlighted in a study. This study evaluated the different tools that have become available for COVID testing and research.


Recent severe acute respiratory syndrome 2 (SARS-CoV-2) known as COVID-19, presents a deadly challenge to the global healthcare system of developing and developed countries, exposing the limitations of health facilities preparedness for emerging infectious disease pandemic. Opportune detection, confinement, and early treatment of infected cases present the first step in combating COVID-19. In this review, we elaborate on various COVID-19 diagnostic tools that are available or under investigation. Consequently, cell culture, followed by an indirect fluorescent antibody, is one of the most accurate methods for detecting SARS-CoV-2 infection. However, restrictions imposed by the regulatory authorities prevented its general use and implementation. Diagnosis via radiologic imaging and reverse transcriptase PCR assay is frequently employed, considered as standard procedures, whereas isothermal amplification methods are currently on the verge of clinical introduction. Notably, techniques such as CRISPR-Cas and microfluidics have added new dimensions to the SARS-CoV-2 diagnosis. Furthermore, commonly used immunoassays such as enzyme-linked immunosorbent assay (ELISA), lateral flow immunoassay (LFIA), neutralization assay, and the chemiluminescent assay can also be used for early detection and surveillance of SARS-CoV-2 infection. Finally, advancement in the next generation sequencing (NGS) and metagenomic analysis are smoothing the viral detection further in this global challenge.

To read more click here.

Oishee MJ, Ali T, Jahan N, et al. COVID-19 Pandemic: Review of Contemporary and Forthcoming Detection Tools. Infect Drug Resist. 2021;14:1049-1082. Published 2021 Mar 17. doi:10.2147/IDR.S289629

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