Eagle Biosciences is excited to announce the newest product series for Host Cell Protein Detection!

Host cell proteins (HCPs) are a major class of impurities produced during biotherapeutic manufacturing. They must be removed from the final drug product to both assure patient safety and maintain drug efficacy. Our wide range of Host Cell Protein Detection Kits are easy to use and highly sensitive.

What are HCPs and why must they be removed from biologic drugs?

HCPs are proteins produced or encoded by the host organisms used to produce recombinant therapeutic proteins. Genetic engineering allows the host organism cells to be transformed to produce a protein of interest. During the recombinant protein production, host cells also coproduce proteins related to the normal cell functions such structural proteins, as well as proteins required for normal cellular growth and function, and vary in both number and concentration depending on the chosen host species and the manufacturing process being used. In general, apart from the therapeutic protein of interest, all endogenous proteins co-expressed by the host cells are called host-cell proteins.

Why must HCPs be removed from biologic drugs?

HCPs must be removed from the final biotherapeutic product to avoid adverse effects. Almost all HCPs carry safety risks as foreign proteins due to the potential to elicit immune response in humans (e.g, cytokine storm). In addition, some HCPs can also act to enhance the immune response to a drug product. Certain HCPs can also affect drug product stability and efficacy if not adequately removed or inactivated.

How are HCPs detected?

ELISAs are widely used for detecting HCPs, where they are generally configured in a sandwich assay format for improved specificity. In this scenario, a microplate-bound antibody is used for analyte capture, then a second analyte-specific antibody (that binds a different epitope on the target molecule) is added to enable detection. By incorporating a reference standard (e.g., a purified protein) into the assay design, it is possible to quantify the analyte of interest and confirm that its concentration meets regulatory requirements. Advantages of ELISA are that it is sensitive and compatible with high sample throughput – key considerations for biopharmaceutical manufacturing.

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

Eagle Biosciences is excited to bring you a wide array of more complement assays!

The complement system is an essential part of the immune system in the human body, playing a crucial role in defending against infections, clearing cellular debris, and promoting inflammation. It consists of a complex network of proteins and molecules that work together to enhance the immune response. The complement system can be activated through three main pathways, the classical pathway, the alternative pathway, the lectin pathway. The complement system is tightly regulated to prevent excessive immune responses and potential damage to host tissues. Various regulatory proteins are involved in controlling the activation and amplification of the complement cascade to maintain a delicate balance between defense and protection.

New Complement Assays

Rat Classical Complement Pathway ELISA Assay Kit
Rat Lectin Complement Pathway ELISA Assay Kit
Rat Alternative Complement Pathway ELISA Assay Kit
Mouse Classical Complement Pathway ELISA Assay Kit
Mouse Alternative Complement Pathway ELISA Assay Kit
Pig Classical Complement Pathway ELISA Assay Kit
Pig Lectin Complement Pathway ELISA Assay Kit
Pig Alternative Complement Pathway ELISA Assay Kit
Pig Complement Pathway ELISA Assay Kits
MASP1/C1-INH Complex ELISA Assay Kit
C3d ELISA Assay Kit
MASP-2 ELISA Assay Kit
Complement Factor H ELISA Assay Kit
Complement Factor D ELISA Assay Kit
Complement Factor I ELISA Assay Kit
Collectin-10 ELISA Assay Kit
Factor B ELISA Assay Kit
sCD59 ELISA Assay Kit
C1s/C1-INH Complex ELISA Assay Kit
Rat Terminal Complement Complex (TCC) ELISA Assay Kit
Mouse C3 ELISA Assay Kit
Mouse C1q ELISA Assay Kit
Mouse C3b ELISA Assay Kit
Mouse C4 ELISA Assay Kit

Find the complete complement product catalog here. If you have any questions about any of these products or our other offerings, contact us here.

Eagle Biosciences will be at AACC in Anaheim, California!

This year AACC is in Anaheim at the Anaheim Convention Center, Sunday July 23th – Thursday July 27th. We will be at booth #1147 from July 25th to July 27th! Come by to learn about the GA-Map Dybiosis Test Lx and more assays that could help you with your microbiome or other research! We will be there to answer any questions you may have, or just stop by and say hi! We love seeing our customers!

Product Highlights

GA-Map Dysbiosis Test Lx: The first and only standardized solution for microbiome profiling! The GA-Map Dysbiosis Test Lx is a simple multiplex stool assay that maps the intestinal microbiota profile for a selected set of bacteria. The GA-map® platform uses probes that target variable regions (V3 to V7) of the bacterial 16S rRNA gene to characterize and identify bacteria present. The targets are identified in a molecular multiplex assay that utilizes the Single Nucleotide Primer Extension (SNuPE) technology patented by Professor Knut Rudi (US6617138). A unique algorithm takes advantage of all the data generated by the detection of the SnuPE products to determine dysbiosis level in the sample. The algorithm is incorporated in the GA-map® Dysbiosis Analyzer software that accompanies the test.

GA-map® Dysbiosis Test Lx Procedure Quick Guide

GA-map Dysbiosis Test

If you have any other questions about these products or our other offerings, contact us here.

Eagle Bioscience’s is excited to highlight the Alpha Synuclein Preformed Fibrils (Type 1) from StressMarq!

About the Alpha Synuclein Pre-Formed Fibrils (Type 1)

StressMarq’s Alpha Synuclein Pre-formed Fibrils (Type 1) are produced with low endotoxin levels, making them the suitable choice for both in-vivo and in-vitro work. Alpha Synuclein PFFs seed the formation of new fibrils from active alpha synuclein monomers, and can be used to induce endogenous alpha synuclein phosphorylation and subsequent Lewy body inclusion formation in neuronal cell culture or for in vitro oligomerization studies.


Alpha-Synuclein (SNCA) is expressed predominantly in the brain, where it is concentrated in presynaptic nerve terminals1. Alpha-synuclein is highly expressed in the mitochondria of the olfactory bulb, hippocampus, striatum and thalamus2. Functionally, it has been shown to significantly interact with tubulin3, and may serve as a potential microtubule-associated protein. It has also been found to be essential for normal development of the cognitive functions; inactivation may lead to impaired spatial learning and working memory4. SNCA fibrillar aggregates represent the major non A-beta component of Alzheimers disease amyloid plaque, and a major component of Lewy body inclusions, and Parkinson’s disease. Parkinson’s disease (PD) is a common neurodegenerative disorder characterized by the progressive accumulation in selected neurons of protein inclusions containing alpha-synuclein and ubiquitin5, 6.

ATTO633 fluorescently-labelled alpha synuclein PFFs (SPR-322) were taken up, transported into the soma, and induced alpha synuclein aggregation in mouse neurocortical primary cells. (A) Neurites filled with fluorescently-labelled alpha synuclein seeds in a microfluidic co-culture system after 24 hours. (B) Alpha synuclein seeds within the soma and neurites of mouse neurocortical primary cells after 24 hours. Experiment and imaging courtesy of Cellectricon.


  1. “Genetics Home Reference: SNCA”. US National Library of Medicine. (2013).
  2. Zhang L., et al. (2008) Brain Res. 1244: 40-52.
  3. Alim M.A., et al. (2002) J Biol Chem. 277(3): 2112-2117.
  4. Kokhan V.S., Afanasyeva M.A., Van’kin G. (2012) Behav. Brain. Res. 231(1): 226-230.
  5. Spillantini M.G., et al. (1997) Nature. 388(6645): 839-840.
  6. Mezey E., et al. (1998) Nat Med. 4(7): 755-757.

The Alpha Synuclein Preformed Fibrils (Type 1) were utilized in the following studies:

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

What is it SpheroRuler intended for?

SpheroRuler is a monodispersed suspension of 1µm diameter spheres coated with 647-fluorophores giving a stable blinking in SMLM microscopy. Their consistent size and geometry make them very practical and reliable standards to assess the accuracy of your x-y or z measurements, 3D reconstruction methods or your image quality. Monodispersed and immobile in solution, they can also be used as rulers, for drift correction or as guides to help localize features on your biological samples.

SpheroRuler is great for dSTORM calibration experiments because you can use it on your preferred support and buffer. And because you get confident with the new biological structure to image. SpheroRuler also produces simple shapes that are easy to study when you are a dSTORM beginner!


  1. Stable Blinking – Suited for use in SMLM microscopy
  2. Consistent Size – Thoroughly characterized by electron microscopy
  3. Spherical geometry – with sharp and thin edges
  4. Immobile – Suitable for drift correction applications
  5. Bio-compatible – Resuspended in an aqueous buffer and usable along biological samples such as cells or tissue sections
  6. Easy-to-Spot – A high fluorescence intensity for practical use as demo or training tools

For more information about this product or any others from the Microscopy line, contact us here.

Eagle Biosciences is excited to highlight the Double-Stranded RNA (dsRNA) ELISA Assay Kit from Krishgen Biosystems! This kit allows sensitive and selective detection of dsRNA molecules (larger than 30-40 bp), independent of their nucleotide composition and sequence. Check out the assay background and highlights below!


Double-stranded (ds) RNA formation is a hallmark of viral infections that is essential for the induction of innate immunity. dsRNA is also involve in gene silencing and produced as a side product during in-vitro transcription-based RNA synthesis. The increasing importance of in vitro-transcribed (IVT) mRNA for synthesizing the encoded therapeutic protein in vivo demands the manufacturing of pure mRNA products. The major contaminant in the IVT mRNA is double-stranded RNA (dsRNA). The nuclei of human cells contain dsRNA that plays a role in natural biological processes however, when dsRNA enters the cells, from the extracellular milieu into their endosome or cytoplasm, it is sensed as a viral invader. All cells are capable of responding to dsRNA through sensors and effectors. Therefore, the elimination of dsRNA from the IVT mRNA is crucial to improve translation of the administered mRNA and to limit induction of cytokines.

This assay works on the sandwich-ELISA principle and uses both J2 (IgG2a) antibody to dsRNA and K2 antibody to dsRNA as capture and detection antibodies. dsRNA-recognition is independent of the sequence and nucleotide composition of the antigen.

dsRNA ELISA Kit Highlights

  • Pre-coated wells
  • Better specificity – using a direct sandwich assay protocol
  • Ready-to-Use – all components included, and prepared

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

The Eagle Bioscience’s 25-OH Vitamin D ELISA Assay Kit has been used in a number of recent publications! These studies range from exploring the effects of vitamin D on cellular responses, molecular immunity, and mycobacterial killing in cattle, to the role of vitamin D, DKK1, hepcidin, and other oxidative stress biomarkers in type 2 diabetes mellitus patients. Check them all out below!

Flores Villalva, Susana. “The Effects of Vitamin D on the Cellular Responses, Molecular Immunity, and Mycobacterial Killing in Cattle.” University College Dublin. School of Agriculture and Food Science, 2022.

Kamel, Amira A., et al. “The Role of Vitamin D, DKK1, Hepcidin and Oxidative Stress Biomarkers in Type 2 Diabetes Mellitus Patients with and without Diabetic Nephropathy.” The Egyptian Journal of Hospital Medicine, vol. 89, no. 2, 2022, pp. 7137–7146.

Blakely, L.P., et al. “Effect of Vitamin D Source and Amount on Vitamin D Status and Response to Endotoxin Challenge.” Journal of Dairy Science, vol. 106, no. 2, 2023, pp. 912–926.

Fernández-Lázaro, Diego, et al. “25-Hydroxyvitamin D Serum Levels Linked to Single Nucleotide Polymorphisms (Snps) (RS2228570, RS2282679, rs10741657) in Skeletal Muscle Aging in Institutionalized Elderly Men Not Supplemented with Vitamin D.” International Journal of Molecular Sciences, vol. 23, no. 19, 2022, p. 11846.

Kumar, Abhai, et al. “Vitamin D and Inflammatory Cytokines Association in Mild Cognitive Impaired Subjects.” Neuroscience Letters, vol. 795, 2023, p. 137044.

Stenhouse, Claire, et al. “Uptake of Phosphate, Calcium, and Vitamin D by the Pregnant Uterus of Sheep in Late Gestation: Regulation by Chorionic Somatomammotropin Hormone.” International Journal of Molecular Sciences, vol. 23, no. 14, 2022, p. 7795.

If you have any questions about our 25-OH Vitamin D ELISA Kit or any of our other offerings, contact us here.

The MedFrontier Intact FGF-23 Assay is developed and manufactured by Minaris Medical! This assay kit is a reliable test that provides a simple and quick assay procedure that yields a broad dynamic range.

What is FGF-23?

FGF-23 (Fibroblast Growth Factor 23) is a protein belonging to the fibroblast growth factor family. FGF-23 is involved in the regulation of phosphorus metabolism. FGF-23 has a molecular weight of approximately 32 kDa. FGF-23 is produced in bone cells. In vivo, FGF-23 is secreted into circulation. A full-length active FGF-23 protein may undergo proteolytic cleavage to generate an inactive c-terminal fragment. The MedFrontier Intact FGF-23 Assay measures ONLY the full-length active form (intact form).

Why Measure FGF-23?

Phosphate plays a critical role in the formation and growth of bones in children and maintaining strength in adults. If there is an imbalance of FGF-23 within the bloodstream, it can cause hyper- and hypophosphatemia. These conditions have been linked to Rickets, osteomalacia, and impaired renal function to name a few.

About the MedFrontier Intact FGF-23 Assay Kit

This is a sandwich Chemiluminescence enzyme immunoassay (CLEIA) kit by using two anti-human FGF-23 mouse monoclonal antibodies. When serum is added to a plate well coated with anti-human FGF-23 mouse monoclonal antibodies, FGF-23 is captured by the immobilized antibodies (1st reaction). After the 1st reaction, the plate is washed. Then, ALP-labeled anti-human FGF-23 mouse monoclonal 2nd antibodies against FGF-23 react to FGF-23 antigens captured by the immobilized antibodies (2nd reaction). After the 2nd reaction, the plate is washed and light detection is performed after adding the luminescence reagent. Each active well of the plate is measured using a luminescence microplate reader and relative light units (RLU) are obtained. The concentration of FGF-23 in serum is calculated with a standard curve generated using the FGF-23 Standard 1 to 6.

Check out the product flyer to learn more!

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

We are excited to bring you the newest addition to our line of Complement Assays, two new Factor P assays – one quantitative and one functional. Developed and Manufactured by Svar Life Science, these kits are designed to work optimally together. These assays are ideal for assisting in the development of next-generation complement therapies!

In addition to measuring the properdin (Factor P) concentration and determining its functionality, the Factor P assays can be easily adapted for more in-depth studies, granting a closer look at the amplification loop of the complement system.

About Factor P

Factor P (Complement P, Properdin, FP) is a positive regulator and an initiator of the alternative pathway (AP) for complement activation. It binds surface-bound C3 and C5 convertases and stabilizes them to amplify the activation cascade1. Factor P binding increases the half-life of the convertase complex approximately 10-fold2. It is suggested, however debated, that Factor P also can initiate complement activation by binding for example cell surfaces or certain biological substrates, recruiting C3b or C3(H2O) and Factor B and thus initiate the AP pathway1,3. Factor P opposes the negative regulation of Factor H that enhances the dissociation of C3b and Bb and mediates Factor I cleavage of C3b to the inactive iC3b3 (Figure 1).

Figure 1: Factor P as stabilizer and initiator of the alternative complement pathway (left) and the opposing negative regulation by Factor H3 (right).

Factor P is not produced in hepatocytes as most complement proteins, but instead by several cell types including monocytes, macrophages, T-cells and granulocytes. It is likely that transient increased concentration of Factor P enhances the AP upon local stimuli4. For example, neutrophils have Factor P-containing granules that are secreted upon stimulation and can enhance the platelet-granulocyte aggregate formation1. In plasma, Factor P is present in a concentration of approximately 4-25 µg/mL5. Factor P is an elongated 53 kDa glycoprotein that oligomerizes in vivo to dimers, trimers or tetramers (P2, P3 and P4) in a ratio of 26:54:20 (P2:P3:P4) in head to tail structures5,6. Mutations, deficiencies, protein levels as well as protein deposits of Factor P are connected to diseases and disorders summarized by Chen et al 3. Deficiencies generally increase the susceptibility for meningococcal disease and other infectious diseases7. Altered serum levels have been associated with for example C3 glomerulopathy, Lupus Nephritis, sepsis and chronic heart failure and IgA nephropathy8.


  1. Blatt, A. Z.; Pathan, S.; Ferreira, V. P. Properdin: A Tightly Regulated Critical Inflammatory Modulator. Immunol Rev 2016, 274 (1), 172–190. https://doi.org/10.1111/imr.12466.
  2. Fearon, D. T.; Austen, K. F. Properdin: Binding to C3b and Stabilization of the C3b-Dependent C3 Convertase. J Exp Med 1975, 142 (4), 856–863.
  3. Chen, J. Y.; Cortes, C.; Ferreira, V. P. Properdin: A Multifaceted Molecule Involved in Inflammation and Diseases. Mol. Immunol. 2018, 102, 58–72. https://doi.org/10.1016/j.molimm.2018.05.018.
  4. Cortes, C.; Ohtola, J. A.; Saggu, G.; Ferreira, V. P. Local Release of Properdin in the Cellular
    Microenvironment: Role in Pattern Recognition and Amplification of the Alternative Pathway of Complement. Front Immunol 2013, 3. https://doi.org/10.3389/fimmu.2012.00412.
  5. Pangburn, M. K. Analysis of the Natural Polymeric Forms of Human Properdin and Their Functions in Complement Activation. The Journal of Immunology 1989, 142 (1), 202–207.
  6. Smith, C. A.; Pangburn, M. K.; Vogel, C. W.; Müller-Eberhard, H. J. Molecular Architecture of Human Properdin, a Positive Regulator of the Alternative Pathway of Complement. J. Biol. Chem. 1984, 259 (7), 4582–4588.
  7. Fijen, C. A. P.; van den Bogaard, R.; Schipper, M. Properdin Defciency: Molecular Basis and Disease Association. Molecular Immunology 1999, 36, 863–867.
  8. Michels, M. A. H. M.; Volokhina, E. B.; van de Kar, N. C. A. J.; van den Heuvel, L. P. W. J. The Role of Properdin in Complement-Mediated Renal Diseases: A New Player in Complement-Inhibiting Therapy? Pediatr Nephrol 2019, 34 (8), 1349–1367. https://doi.org/10.1007/s00467-018-4042-z.

If you have questions about these new items, or any of our other offerings, contact us here.

We are excited to bring you the new Rat NT-proBNP ELISA Assay Kit! This product has been developed, validated, and manufactured by Biomedica in Austria. This assay extends our robust line of kits specific to cardiac biomarkers. Learn more below!

Biomarker Background

BNP is mainly expressed by the ventricular myocardium in response to volume overload and increased filling pressure. It is synthesized and secreted by cardiomyocytes. Mature BNP consists of 108 amino acids (proBNP or BNP-108). ProBNP is cleaved during secretion in a 1:1 ratio resulting in physiologically active BNP-32 and the biologically inactive 76 amino acid NT-proBNP. NT-proBNP (1-76) has greater plasma stability and a much longer biological half-life (90-120 minutes) than BNP, being considered as the preferred laboratory marker. BNP has a key role in cardiovascular homeostasis with biological actions including natriuresis, diuresis, vasorelaxation, and inhibition of renin and aldosterone secretion. A high concentration of BNP in the bloodstream is indicative of heart failure.

Rat NT-proBNP ELISA Assay Kit Features

  • Low Sample Volume Required – 10 µL/well
  • Controls Included
  • Sample Values Provided

Related Products

NT-proBNP ELISA Assay Kit
NT-proCNP ELISA Assay Kit
NT-proANP ELISA Assay Kit
BNP Fragment ELISA Kit

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