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Dopamine Sensitive ELISA Assay Utilized in Recent Publication

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.

What is Stencell intended for?

Stencell is used notably for wound-healing assay & immunocytochemistry experiments. It is very helpful when you are working with super expensive reagents or very rare cell lines, and when you want to test various experimental hypothesis.

Stencell for wound-healing experiments


Stencell Designs

Each sheet is composed of 50 identical Stencells. Upon receipt of your purchase order, you will be able to choose either the same design for your 2 sheets, or 2 different designs for your 2 sheets (1 per sheet of 50).

    • Solo: 1 circular well – Diam. 12 mm
    • Quartet: 4 circular wells – Diam. 3 mm
    • Nonet: 9 circular wells – Diam. 3 mm
    • Presto: 2 oblong wells spaced by 0.35 mm
    • Allegro: 2 oblong wells spaced by 0.62 mm


    Features

    1. Design your PDMS – Our design process offers total freedom to turn your idea into a PDMS.
    2. Stack and Play – Compose flow channels and chambers, stacking different designs of Stencell.
    3. Stick it to a variety of culture labware – So far, it has been successfully stuck onto the following: glass slides, plastic dishes, Transwell(R) inserts, Polyacrylamide gels.
    4. Remove it – Stencell is not glued. It can then be removed to trigger cell migration, switch from flow chamber to open window. (Very useful for wound healing experiments)
    5. It is compatible with imaging – These thin sheets of silicone are fully transparent, without autofluorescence.
    6. Parallelized and standardized experiments – One multiwell Stencell can perform several experimental conditions.
    7. It saves samples and reagents – Only a few microliters are required.


    Key Conditions of Success

    • When you remove the inner elements of your Stencell, use 2 tweezers: 1 to remove and the other 1 to press close to the junction in order to avoid breaking the Stencell. Alternatively, you can cut the junctions with a scalpel.
    • When you put the Stencell on top of your culture substrate, softly remove the bubbles and stick the Stencell, patting it with tweezers.
    • Depending on the substrate hydrophobicity, the droplet might not completely fill the well. You can:
      • Either fill the well with the standard volume. Then, help the droplets stick to the Stencell by connecting the liquid next to the Stencell walls using the pipette tip.
      • Or, you may add an excess volume of liquid (e.g. 30 μL) and remove it afterwards (e.g. 10 μL).
    • But: do not overfill (e.g. > 30 μL) the wells, otherwise two droplets may merge.
    • When you put your substrate and cells in the incubator. Wait for 1 to 2 hours until cells spread and fully occupy the windows space. If you need to wait longer, be sure that the droplets do not completely evaporate.

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

What is it Stampwell intended for?

Stampwell is highly helpful if you have tons of 3D samples to image. The V-shape Stampwell is used to image them (2 different sizes). And the Rectangular Stampwell is designed to image Zebrafish or Medaka embryos. It avoids spending hours to locate your sample in the dish. It prevents them from slipping from one well to another when you move your dish from the incubator to the microscope. And it allows to image and observe how your biological samples grow over several weeks.


3 Shapes of wells to choose freely and best fit your experiments:

  • V Shape: 7*6 pins in V-shape – Diameter 26mm – Exists in 2 different sizes: 300 or 500u
  • Rectangular:7*5 rectangular – Diameter 26mm
  • “My Shape”: design your wells, adapted to your samples and your experimental needs!


Features of Stampwell

  1. Cross-platform – Compatible with most 35 mm dishes and 6-well plates.
  2. Reusable – Use your stamp dozens of times.
  3. Medium Culture Conditioning – U Shape: the design of a groove increases the culture medium conditioning and cell aggregates survival.
  4. Long-term imaging over weeks with V-shape and Rectangular – the sample just lays on the bottom of the well and can freely grow within it.
  5. Safe transport of 3D objects – V-shape and Rectangular keep your samples at the bottom of the wells, even when the dish is upside down.
  6. Automatized multi-position image acquisition V-shape and Rectangular – provide a constraint-free but stable and parallelized immobilization of the samples.
  7. Customize your shape – My-Shape is your own design and number of wells. Contact us for details.


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

What is Everspark intended for?

Everspark is a hassle-free buffer used to decouple the preparation of your samples and their imaging. Use it if you need to prepare your samples in your lab and image them in your core facility 3 to 4 weeks later. Everspark is also compatible with imaging that uses red, far-red and green dyes (eg. AF488). Different colors can be used either at the same time or one after the other.


Features

  1. High stability over time for repeated measurements – One mounted sample is stable over 3 to 4 weeks and can be imaged multiple times
  2. Multicolor (including green) – Compatible with green, red, and far red dyes (JF646, JF549, AF647, DL550, CF568, DL650, CF680, SulfoCy5 and mEos2)
  3. Ready to Use – Can be used directly from the vial
  4. Up to 6 months performance – Individualized packaging for optimal longevity
  5. Techniques – PALM, dSTORM, HILO, TIRF pattern
  6. Customizable – Choose the MEA concentration, pH, optical index, or even additives


Use Method:

  • Rinse the coverslip with sterile water
  • Discard water in excess
  • Prepare sealant: 1 volume of sealant catalyst + 1 volume of sealant basis in a micro-dish – do not mix
  • Open the Everspark tube and pipette right away the desired volume onto a Wilco glass bottom dish
  • Flip the coverslips face towards the slide on the cavity filled with Everspark without making bubbles
  • Absorb excess of Everspark buffer on the sides with a kimwipe
  • Mix sealant
  • Seal quickly with the reconstituted sealant
  • Wait for the sealant to polymerize on the slide before moving the slide
  • Discard the open tube of Everspark buffer (cannot be used for another slide, once already opened)
  • Gently clean the coverslip with 70% ethanol
  • Perform regular dSTORM acquisition (best to wait a couple of hours)
  • Repeat dSTORM acquisition 24 hours up to 3 weeks on the same slide providing no air bubbles were present
  • Store the slides at 4°C and in the dark before repeating dSTORM acquisition on the same slide (up to 3 weeks)

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

Circulating DKK-1 levels predict disease outcomes and mirror metabolic adaptations in patients with Covid-19

Individuals with low serum levels of DKK-1 (Dickkopf-1) are twice as likely to die from Covid-19 than those with high levels according to new research published by Nikolai Jaschke and colleagues in the Journal of Clinical Endocrinology & Metabolism.

The researchers found that circulating DKK1 levels vary in humans and change as a function of time during SARS-CoV-2 infection. The infection promotes metabolic adaptations that resembles fasting, which are mirrored by circulating DKK1 levels. DKK-1 levels predict disease outcomes in Covid-19 individuals.

The results of the study suggest a potential use of measuring circulating DKK1 as an indicator of disease severity in COVID-19 patients.


Abstract

Context and aims: Coronavirus disease 19 (COVID-19) trajectories show high interindividual variability, ranging from asymptomatic manifestations to fatal outcomes, the latter of which may be fueled by immunometabolic maladaptation of the host. Reliable identification of patients who are at risk of severe disease remains challenging. We hypothesized that serum concentrations of Dickkopf1 (DKK1) indicate disease outcomes in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected individuals.

Methods: We recruited hospitalized patients with PCR-confirmed SARS-CoV-2 infection and included 80 individuals for whom blood samples from 2 independent time points were available. DKK1 serum concentrations were measured by ELISA in paired samples. Clinical data were extracted from patient charts and correlated with DKK1 levels. Publicly available datasets were screened for changes in cellular DKK1 expression on SARS-CoV-2 infection. Plasma metabolites were profiled by nuclear magnetic resonance spectroscopy in an unbiased fashion and correlated with DKK1 data. Kaplan-Meier and Cox regression analysis were used to investigate the prognostic value of DKK1 levels in the context of COVID-19.

Results: We report that serum levels of DKK1 predict disease outcomes in patients with COVID-19. Circulating DKK1 concentrations are characterized by high interindividual variability and change as a function of time during SARS-CoV-2 infection, which is linked to platelet counts. We further find that the metabolic signature associated with SARS-CoV-2 infection resembles fasting metabolism and is mirrored by circulating DKK1 abundance. Patients with low DKK1 levels are twice as likely to die from COVID-19 than those with high levels, and DKK1 predicts mortality independent of markers of inflammation, renal function, and platelet numbers.

Conclusion: Our study suggests a potential clinical use of circulating DKK1 as a predictor of disease outcomes in patients with COVID-19. These results require validation in additional cohorts.

Check out the full article here.


Circulating DKK-1 levels were measured with the DKK-1 ELISA from Biomedica

  • Small sample volume – 20µl serum/well
  • Reliable –international validation guidelines
  • Easy – direct measurement
  • Widely cited in +170 publications

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

What is Chitozen intended for?

Chitozen is used to image bacteria both still and alive under the microscope, or it can be used to perform long-term imaging of bacteria. It can also be used if you want to change the growth condition (e.g. antibiotics, chemicals, inhibitors) during the experiment and directly observe, in real-time, the bacteria new comportment under the microscope.

E.coli monolayers on Chitosan


For what bacteria is Chitozen used for?

Chitozen has been tested with the following bacteria: E. coli, Vibrio cholerae, Myxococcus xanthus, Mycobacterium smegmatis, Bacillus subtilis, Pseudomonas aeruginosa and Pseudomonas fluorescens. More bacteria being currently tested.

Growth of E.coli on Chitozen


Simplified Protocol


Features

  1. Full compatibility with most of your conditions of experiments – Size: the coverslip dimension (25x75mm) is compatible with the most common available sticky slides and microscope stages; it is also compatible with advanced microfluidic techniques, nanolithography
  2. 6 independent channels – Either perform up to 6 experiments at the same time or use 1 channel one day, and the others later
  3. Ready and fast – Assemble it within 2 minutes, use it the same day as its prepared
  4. Long lasting – A bench-stable surface coated with chitosan, the most efficient way to immobilize your bacteria on a microscope coverslip; storable for 2 months once assembled


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

What is Actiflash intended for?

Actiflash is used to convert your inducible ERT model into a photo-inducible one. Use it if you want to control transcription (using Gal4-UAS) or induce recombination (using Cre-lox) in space and/or time for in-vivo cell tracking experiments and more. Actiflash is for research use only


Features

    1. Wide applicative scope – Technology capitalizing on the versatile use of Tamoxifen-OH for controlling functions of multiple types of proteins.
    2. Simple conditioning – Caged Cyclofen-OH is cell-permeant and can be added either in the external medium or directly injected for conditioning.
    3. Excellent chemical stability – Caged Cyclofen-OH does not generate any basal activation of protein function and it benefits from an excellent temporal resolution upon uncaging.
    4. Favorable wavelength ranges for uncaging – Uncaging requires either UV-A light or a strong IR laser. Visible light is inactive, which facilitates the experiments with biological samples.
    5. Photochemical stability – Caged Cyclofen-OH liberates Cyclofen-OH, which is photostable in contrast to Tamoxifen-OH encountering photodegradation under illumination.


Method of Use:

Calibration of the Actiflash concentration
It is advised to first establish the extent of phenotype sought for as a function of the Tamoxifen-OH concentration. Then the concentration of Actiflash used for sample conditioning is fixed at Tamoxifen-OH concentration causing 100% of the desired phenotype (in general 3-5 μM in cultured cells and zebrafish embryos).

Conditioning protocol
Incubate your samples in a serum-free medium for 90 mins, away from light.

Photoactivation
Illumination of Actiflash may be performed with UV (325-425nm range) light or multiphoton excitation (at 750 and 1064 nm with two- and three-photon excitation, respectively) to release Cyclofen-OH. You can use either benchtop UV lamps or light sources installed on microscopes.

The calibration of the photoactivation
The objective is to provide enough photons to exhaust the conversion of the Actiflash but without generating detrimental side-effects on the biological sample. Simply analyze the phenotype recovery with decreasing illumination duration. Then determine the shortest illumination duration leading to 100% uncaging of Actiflash.


5 Key Conditions of Success

  1. Actiflash is provided as a powder. Resuspend it with DMSO (warning: no water).
  2. Only unfreeze the aliquots you need for your experiment.
  3. Carefully calibrate the photoactivation of Actiflash (concentration for conditioning, power of the light source, geometry and duration of illumination). Then always work under the same conditions.
  4. Use a serum-free medium during the incubation step of the cell lines.
  5. In the dark, just before photoactivation, wash your samples (unnecessary for two-photon laser experiments).


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

Eagle Biosciences, Inc. is excited to partner with Idylle to bring you an exciting new variety of products!

Idylle is a unique company that is based in France. Their facilities include a state of the art tech transfer platform that works to bring innovation into life science workflows. They produce some of the most innovative R&D tools, side by side with researchers who design, test, and use them. Their products are easy to handle research tools that have been approved by the scientific community using Idylle’s unique ‘Test Programs’. These Test Programs are a four-week trial that allows researchers to test the products in their workflow and share their feedback.

We will be offering some of these products in a microscopy line that is intended to help improve your imaging needs. Check out the items below, and follow along in the upcoming weeks as we take a deep dive into each item.


Microscopy Products

Actiflash – Stable Tamoxifen-like photoactivable inducer.

Chitozen – The 1st functionalized microscope coverslip to image live bacteria

Everspark – Ready to use super-resolution microscopy buffer.

Stampwell – A family of stamps to democratise the 3D culture.

Stencell – The PDMS no-brainer solution for all micro-volume experiments, anywhere.


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


Eagle Biosciences, Inc. is continuing to work with BPM Biotech in the support the Fetuin A (PTM) ELISA (DNlite-DKD)!


About Fetuin A (PTM) ELISA

This Fetuin A (PTM) ELISA (DNLite-DKD) measures a unique biomarker that can have great impact on those with diabetic kidney disease (DKD). The Fetuin A post translation modifications (PRM) measured in this assay was identified in a large-scale profiling of urinary proteomics. This new biomarker can help predict the kidney condition of diabetes patients, months to years in advanced. This urine test can help predict kidney decline or complications and potentially improve a patient with diabetic kidney disease quality of care.


Check out the flyer below for a comprehensive look at this unique test!


Other Reference Materials

Instructions for Use
Acute Kidney Disease in the Outpatient Setting


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

Dopamine Sensitive ELISA Assay Utilized in Recent Publication

The Eagle Bioscience’s 25-OH Vitamin D ELISA Assay was highlighted in a recent publication that explored the relationship between vitamin D and leptin hormones in type 2 diabetes mellitus patients from Kuwait. Check out the full text and abstract below.


Abstract

Background: Type 2 diabetes mellitus (T2DM) and obesity are prevalent in Kuwait. Vitamin D (VD) deficiency and leptin resistance are risk factors for both disorders. A correlation between the two risk factors has been suggested albeit inconsistently reported. Our objective was to determine the effect and association of VD and leptin levels and their related common variants with T2DM.\

Methods: This case-control study included 203 Kuwaiti T2DM patients and 162 healthy Kuwaiti controls. Leptin and VD levels were measured using enzyme linked immunosorbent assays. Genotyping of LEP rs7799039, LEPR rs1137101, VDRrs2228570 and rs731236 was performed using Taqman genotyping assays.

Results: Leptin levels were higher in T2DM patients than controls, but vitamin D levels did not differ. No correlation was found between the levels of the two hormones. VDR rs731236G associated with T2DM risk (Odds ratio 1.66, p=0.0008). VDR haplotype analysis revealed GG/AA, GA/AA or GG/AG to associate with T2DM risk (p=0.01) and increased risk of diabetic neuropathy (p=0.002). VDR rs2228570GG associated with leptin levels in T2DM (p=0.01). Effect of LEP rs7799039 on leptin (p=0.01) and VD levels (p=0.02) was only evident in healthy controls.

Conclusions: VDR rs731236G is associated with T2DM risk in Kuwait, and a VDR haplotype of a less active, low expressing VDR is associated with T2DM and diabetic neuropathy risk. Common variants in leptin and VD related genes appear to mediate the suggested positive correlation of both hormones however their influence is disrupted in T2DM.

Lari F., Alabduljaleel T., Mojiminiyi O., et al. Exploring the Relationship Between Vitamin D and Leptin Hormones in Type 2 Diabetes Mellitus Patients from Kuwait. J Horm Mol Biol Clin Investig. 2022; 10.1515/hmbci-2021-0091


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