For Cytokine Profiling, xMAP® Technology Outperforms ECL Kits

Multiplex immunoassays compared with brain cancer biomarker detection

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Accurately staging any cancer can be challenging, but assessing glioblastomas hidden in the brain is even more difficult. Scientists are working hard to discover and validate blood-based biomarkers that could provide useful prognostic and diagnostic information for these malignancies while overcoming the major accessibility issue associated with brain tumors. Cytokines are especially promising since they are released as part of the natural immune response to glioblastomas.

Recently, a team of scientists at Washington University School of Medicine aimed to evaluate the performance of two different multiplex immunoassay techniques for cytokine profiling in plasma samples from patients with brain tumors and healthy volunteers. They compared an assay on the Luminex ® Technology” href=”/xmap-technology/#overview”>xMAP Technology can streamline your workflow and expand your research, we’ve developed a free cost comparison tool that demonstrates how much time and money you can save by entering your custom lab parameters.

Read the full study from Washington University here.

For Research Use Only. Not for use in diagnostic procedures.

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Mayo Clinic Scientists Validate xMAP® SARS-CoV-2 Serological Assay with Dried Blood Spots

Dried blood spot sample type is less invasive and easier for labs to manage

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SARS-CoV-2 antibody testing has been well established, but requiring a full blood draw from each individual is invasive and requires a phlebotomist. Now, scientists at the Mayo Clinic have a solution: they validated the Luminex paper published in PLoS One, researchers note that the ability to test dried blood spots would be an important step in expanding serological testing associated with the COVID-19 pandemic. To determine whether scientists could use blood spot samples for SARS-CoV-2 antibody detection, the researchers tested nearly 160 paired samples of dried blood spots and serum specimens collected from the same person. The samples were run using the xMAP assay and two other commercially available assays for comparison.

The Mayo Clinic team had previously validated another SARS-CoV-2 serological assay with dried blood spots, but they found that its high false-positive rate necessitated confirmatory testing, which required a standard blood draw sample. To avoid this, they turned to the multiplex xMAP assay. Because this assay detects IgG for three viral antigens—the spike protein, receptor-binding domain, and nucleocapsid—it is less likely to produce false-positive or false-negative results. In addition, the low sample volume requirements for the xMAP assay make it a good fit for use with dried blood spots.

“We show excellent correlation of results between the modified Luminex xMAP assay performed on [dried blood spot] specimens and the comparator assays with FDA EUA performed on serum,” the team reports. Overall concordance was 96.9%—the authors describe it as “almost perfect agreement”—and went up to 99.4% with the implementation of pattern recognition software designed to adjust detection thresholds.

Compared to other dried blood spot tests, the scientists note that their technique requires the smallest amount of blood: just a 3 mm punch, or about 3.2 μL of whole blood. This allows “some latitude to the quality and amount of finger stick blood collected on the card, which minimizes the need for repeat collection,” they noted.

A high-throughput, reliable testing option

The modified xMAP method also scales well for labs performing high-throughput serology testing. “The extraction, processing, and analysis of 92 patient samples and 4 controls/calibrators can be completed within 6.5 hours by a single technologist,” the team notes. “This protocol allows for a throughput of 644 samples, completed by two technologists using one analyzer, within an 8-hour shift.”

“The Luminex xMAP workflow [for dried blood spots] … presents an attractive and safe means to perform community or institutional seroprevalence studies,” the scientists conclude.

To learn more about the xMAP SARS‑CoV‑2 Multi-Antigen IgG Assay (EUA)—a comprehensive multiplex assay that enables rapid and reliable detection of SARS-CoV-2 antibodies—please visit our here.

Learn more about the xMAP SARS-CoV-2 Multi-Antigen IgG Assay (EUA) here.

(EUA) In Vitro Diagnostic Use Under Emergency Use Authorization. This test has not been FDA cleared or approved. This test has been authorized by the FDA under an EUA for use by authorized laboratories.

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First Impressions: New Users Get Up to Speed on xMAP® Technology

Luminex interns share what they wish people knew about multiplexing

Scientists who use To help emerging scientists bridge the gap from college to careers in the life sciences, we offer an internship program in our LuminexPLORE custom assay development lab, where we introduce our interns to xMAP Technology. They’ve already become pros in the short time they’ve been here, and they have made valuable contributions to projects while helping turn our clients’ dream assays into reality.

We recently spoke with Atharwa Mankame and Katie O’Connor, both graduating seniors at The University of Texas at Austin this spring, to learn more about their experiences and what they learned as new xMAP users. They gave us some insight into their introductions to bead-based multiplexing.

Learning about xMAP Technology

“[Multiplexing] lets you maximize the usage of each sample to make sure you’re getting the most out of what you have.”

— Katie O’Connor, LuminexPLORE Lab Intern

Both interns were unfamiliar with xMAP Technology when they started, but they got up to speed quickly and discovered the value of multiplexing. “You use less resources and you save a lot of time. Multiplexing helps you finish everything faster,” Mankame said. “If you want to test for one target in one sample on an ELISA, that takes maybe six hours. But if you have 10 targets to run in triplicate, that’s two weeks of testing versus one day for xMAP.” That capacity resonated with him since he had previously run several singleplex ELISAs in his university lab, where the process took an entire month. “With multiplexing in the LuminexPLORE lab, we’re doing four plexes every two hours,” he said.

According to O’Connor, multiplexing is “also really nice for consistency, particularly for limited volume samples. It lets you maximize the usage of each sample to make sure you’re getting the most out of what you have.” She noted that the ability to design custom assays is also valuable.

Hands-on experience in the LuminexPLORE lab

The interns learned through firsthand experience how multiplexing reduces time at the bench, freeing up each scientist to spend more time analyzing results and planning future experiments. “The best part about the LuminexPLORE lab is that it only takes an hour to prep your project, and then you have the rest of the day to analyze your data, talk to clients, and take care of other tasks,” Mankame said.

Tips and tricks from the lab

We also asked the interns about the best tricks they’d learned. “Vortex and sonicate to maintain even distribution of beads in solution and maximize contact surface area and accuracy of assays,” O’Connor told us.

“Pre-wet your tips to maintain consistency during aspiration,” Mankame said.

“The best part about the LuminexPLORE lab is that it only takes an hour to prep your project, and then you have the rest of the day to analyze your data, talk to clients, and take care of other tasks.”

— Atharwa Mankame, LuminexPLORE Lab Intern

Both interns enjoyed their time and education in the LuminexPLORE lab. “It’s been really cool working with people who developed xMAP Technology and helping to optimize assays for scientists who are using these platforms,” O’Connor said.

Whether you’re an intern or an experienced researcher, we have multiple resources to help you get started with xMAP Technology or explore custom assay development. Our xMAP Cookbook is a free collection of methods and protocols for developing your own assays, and is available for download here. To learn more about LuminexPLORE Lab, our custom services program designed to help accelerate your research, click here.

Learn more about LuminexPLORE Lab, our custom services program.

Accelerate Your Research

For Research Use Only. Not for use in diagnostic procedures.

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Selecting the Right Plate Magnet for Luminex Assays

With the introduction of MagPlex® beads, more streamlined protocols can be developed for protein and nucleic acid applications.

With magnetic beads, high throughput experiments being done in 96 well plates or higher formats no longer need to have washing and other buffer exchange steps done by spinning plates or washing beads with filter plates. Such steps increase processing times, prevent developing automated protocols, and contribute to bead loss and higher CVs. By switching MicroPlex® bead assays to MagPlex® beads, protocol times can be shortened, and lower bead loss generates more reliable and reproducible data.

Because a large number of different plate magnet designs are available, selection of the right plate magnet is critical to maximize the advantages of using MagPlex® beads. Four different plate magnets designs include 1) flat plate magnets, 2) bar magnets, 3) post magnets, and 4) Ring magnets (Table 1). Several factors need to be considered to determine which magnet design fits your needs best. One of the first factors to consider is the type of assay it is used for, a protein based assay or nucleic acid assay with PCR steps and/or heated reading.

Many protein-based assays can be done in flat bottom microtiter plates and processed manually with or without plate washers. These types of assays can use flat plate magnets—where the entire bottom of the magnet is magnetized. While this type of magnet may be suitable for low sample number experiments processed manually, higher throughput experiments employing more automated handling may require a shift to bar-, post-, or ring-type magnets—especially when they need to shift away from flat bottom plates and need plates with conical or curved wells. In this case, several other factors similar to those required for nucleic acid assays need to be considered as described below.

Most nucleic acid assays—especially those with PCR steps—can be processed manually or with semi-automated protocols. Due to the sensitivity of the PCR steps, it is crucial to prevent cross contamination between wells on the plate. As a result, whether using a manual processing protocol or automated protocol, disposable tips are required to eliminate any cross contamination between wells on the plates. In addition, the need to run reactions in a thermal cycler or analyze in the Luminex heater block requires the use of PCR plates with conical shaped wells.

During different steps in the protocols and during washing steps, these assay characteristics require the complete removal of buffers from the wells with minimal bead loss. This requires a magnet design that will pull the beads to the sides of the wells so that pipette tips can go all the way to the bottom for complete removal of reaction buffers. For PCR-based nucleic acid assays and high throughput protein assays employing conical well plates, the two following factors must to be considered.

  1. At any step in the protocol when the magnet is needed and the plate fits securely on the magnet, is the reaction volume large enough that the top of the solution is above the top of the magnet? If the top of the solution is below the top of the magnet, beads can be pulled out of the solution, dramatically altering the reliability of the assay (Figure 1).
  2. Is the magnet strong enough to pull the beads out of the way in a short period of time? Reaction solutions can have different viscosities and will require different strength magnets. So the strongest magnet that also meets the needs of requirement 1 above will be the preferred magnet—especially if it can clear the solution of beads within 2 minutes or less.

So whether you are designing a multiplex proteomic assay or nucleic acid assay, keep these guidelines in mind when selecting a plate magnet. If you need further recommendations for the best magnet for your specific Luminex application, contact Luminex technical support or your Field Application Scientist for more information.

3 New Studies Show How xMAP INTELLIFLEX® Delivers Double the Data

Get two results per analyte with our new dual reporter feature

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In the newest generation of our INTELLIFLEX® DR-SE System, we’ve added more than a few exciting features, including the unique dual reporter functionality powered by a second reporter laser. Designed to increase data output while using less sample, this new feature allows users to collect double the amount of data for each analyte in a multiplex study.

To show how this capability could make a difference in various applications, we’ve recently published a ® System” href=”/blog/new-software-offers-a-streamlined-user-experience-for-the-xmap-intelliflex-system/”>software, and more.

If you’d like to learn more about the new features in the INTELLIFLEX platform, check out the other available technical documents Read the full tech note.

For Research Use Only. Not for use in diagnostic procedures.

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At Norway-Based Genetic Analysis, Scientists Multiplex Biomarkers to Measure Gut Microbiome Health

xMAP® Technology powers a commercial assay spanning 50 biomarkers

Our research Partners are an invaluable part of our team, connecting the xMAP® community with powerful, customizable kits and application and product expertise. On our blog, we’d like to shine the spotlight on our unique Partners and the work they’re doing with Genetic Analysis offers testing to help physicians understand the health of their patients’ gut microbiomes. We profiled their team in 2017, and since then, they’ve made exciting progress in a few key areas.

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Scientists at Genetic Analysis developed the

The team started building its reference profile based on samples from healthy donors in small countries with less diverse populations: Denmark, Sweden, and Norway. “We found a set of markers that were always present in the healthy population,” Dr. Hegge said. After that, the team expanded to Germany, Spain, and Italy. “We found that those markers were also valid for those countries,” he added. Now, the company is analyzing samples collected in the much more heterogeneous United States and aims to move to China next.

Genetic Analysis Quote

As this core set of biomarkers is validated in more populations, the Genetic Analysis team is also collaborating with universities and hospitals to document how useful the test is for guiding disease treatment, monitoring disease progression, and analyzing fecal microbiota transplants.

When the dysbiosis test was initially conceived in an academic lab, it was originally based on microarray technology, but Dr. Hegge and his colleagues knew that approach wouldn’t scale for the high-throughput lab they built as the test was being commercialized. Likewise, qPCR assays couldn’t multiplex to cover 50 different biomarkers. They identified xMAP Technology as a strong candidate because it could analyze many different biomarkers in a single tube. The team also liked Luminex’s reputation. “We wanted a Partner that was bigger and stronger than ourselves,” Dr. Hegge said.

Achieving growth and increased value with a Luminex Partnership

As a Luminex research Partner, we support Genetic Analysis with their marketing and technical efforts. “Luminex understands the challenges of small companies and that things don’t always happen as planned,” Dr. Hegge said. “They are very helpful and responsive. I would definitely recommend Luminex as a Partner.”

Our Partners are a diverse group of industry leaders representing different market segments and expertise areas. To learn more about Genetic Analysis, visit their website. For more information about the benefits of becoming a Luminex Partner, you can check out our Partner page.

Learn more about the benefits of becoming a Luminex Partner here.

For Research Use Only. Not for use in diagnostic procedures.

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