Ten Things to Know about Inducible T Cell Co-stimulators (ICOS)

The term ICOS —inducible T cell co-stimulators— has been prominent in my work as a science writer at Promega, recently. Here is a brief look at ICOS, how it works, and how it can be used in therapeutics research and development.

T cells do amazing things, like driving or blocking production of B cells and their related antibodies and antibody maturation, and they are the primary drivers of innate immunity. T cells have a variety of surface molecules, the primary and omnipresent T cell receptor (TCR), as well as CD3.

Schematic diagram of a T cell receptor TCR. The TCR interacts with ICOS in the immune response.

In the past 15 years or so, researchers have identified other, inducible receptors on T cells. These receptors appear when T cells are stimulated, enabling interactions with other cell types. The following information is summarized from a Frontiers in Immunology review by Wikenheiser et al.

What is ICOS (inducible T cell co-stimulators)?

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Celebrating 30 Years of “Glo-ing” Research

This post is written by guest blogger, Amy Landreman, PhD, Sr. Product Manger at Promega Corporation.

In December of 1990, Promega first discussed the use of firefly luciferase (luc) as an emerging reporter technology in the article, Firefly Luciferase: A New Tool for Molecular Biologists. At the time, the gene coding chloramphenicol acetyltransferase (cat)  was most commonly used by researchers, but it was thought that the bioluminescent properties of firefly luciferase, extreme sensitivity and rapid simple detection, could make a significant difference in how molecular biologists tackled their research. Several months later, the first firefly luciferase reporter vectors and detection reagents became available as products, making this new technology more broadly accessible to the research community. Today firefly luciferase is no longer a “new tool”, with it and many other bioluminescent reporter technologies being standard elements of the modern research toolbox.

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Intranasal COVID-19 Vaccines: What the Nose Knows

COVID-19 vaccine distribution efforts are underway in several countries. Recently, the Serum Institute of India celebrated the nationwide rollout of its Covishield vaccine, kicking off the country’s largest ever vaccination program. Meanwhile, many other vaccines against the coronavirus that causes COVID-19 are in either preclinical studies or clinical trials. At present, 19 vaccine candidates are in Phase 3 clinical trials, while 8 vaccines have been granted emergency use authorization (EUA) in at least one country.

intranasal covid-19 vaccine coronavirus

In the US, mRNA vaccines from Pfizer/BioNTech and Moderna are in distribution. Adenoviral vector vaccines authorized for distribution include Oxford/AstraZeneca AZD1222 in the UK (Covishield in India) and Gamaleya Sputnik V in Russia. A third type of vaccine consists of inactivated coronavirus particles, such as those developed by Sinopharm and Sinovac in China.

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Bioluminescence and Biotechnology: Shining Nature’s Cool Light on Biology

Imagine you’re taking a refreshing night swim in the warm blue waters of Vieques in Puerto Rico. You splash into the surf and head out to some of the deeper waters of the bay, when what to your wondering eyes should appear, but blue streaks of light in water that once was clear. Do you need to get your eyes checked? Are you hallucinating? No! You’ve just happened upon a cluster of dinoflagellates, harmless bioluminescent microorganisms called plankton, that emit their glow when disturbed by movement. These dinoflagellates are known to inhabit waters throughout the world but are generally not present in large enough numbers to be noticed. There are only five ecosystems in the world where these special bioluminescent bays can be seen, and three of them are in Puerto Rico. 

Bioluminescent plankton exhibit a blue glow when disturbed.
Bioluminescent plankton in the ocean

But you don’t have to travel to Puerto Rico or swim with plankton to see bioluminescence. There are bioluminescent organisms all over the world in many unexpected places. There are bioluminescent mushrooms, bioluminescent sea creatures—both large and small (squid, jellyfish, and shrimp, in addition to the dinoflagellates)—and bioluminescent insects, to name a few. Bioluminescence is simply the ability of living things to produce light.

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Exploring the Virtual iGEM Giant Jamboree with iGEM Concordia

Today’s guest blog about the 2020 virtual iGEM Giant Jamboree is written by Lancia Lefebvre, Team Leader of iGEM Concordia.

AstroBio database for differential gene expression

After a year of full-time work, I joined our team of 16 undergraduate students to live-stream the virtual iGEM Giant Jamboree from the isolation of our respective apartments. Together in a separate zoom call and Facebook chat, we fired off messages as awards were announced. ‘OMG Toulouse won best poster! Did you see Aachen’s project?’ Then came the Software Track award, our track, and boom! “Concordia-Montreal are the Software Track Winners for iGEM Giant Jamboree 2020!”

Firework and heart emojis exploded in our chat and on my zoom call, mouths gaped in shock and pride. Our AstroBio database for differential gene expression in microgravity conditions had won! Innumerable lines of code; hours of consultation with NASA bioinformaticians, bioethicists and coding pros; detailed graphic design; and most of all passionate teamwork had brought us this distinction. A gold medal and an inclusion nomination soon followed. This nomination we hold close to our heart as we continuously collaborate on a safe, warm and welcoming team structure. Supporting each other and working together are core iGEM values, which lead to collaborative and stronger solutions to world problems through the application of synthetic biology solutions.

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Barking Up the Right Tree: Using NanoLuc to Screen for Canine Distemper Antivirals

Canine distemper virus (CDV) is a highly contagious pathogen that is the etiological agent responsible for canine distemper (CD), a systemic disease that affects a broad spectrum of both domestic dogs and wild carnivores. While there are commercially available vaccines for CDV that can provide immunity in vivo and protect canines from contracting CD, there is a strong demand for effective canine distemper antivirals to combat outbreaks. Such drugs remain unavailable to date, largely due to the laborious, time-consuming nature of methods traditionally used for high-throughput drug screening of anti-CDV drugs in vitro. In a recent study published in Frontiers in Veterinary Science, researchers demonstrated a new tool for rapid, high-throughput screening of anti-CDV drugs: a NanoLuc® luciferase-tagged CDV.

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Targeting Glioblastoma Cells by Packaging a Lentiviral Vector Inside a Zika Virus Coat

A recent article published in Cancers demonstrates a new method for targeting glial cells using a lentiviral packaging system that incorporated Zika virus envelope proteins. By using the reporter gene firefly luciferase, researchers demonstrated that a pseudotyped virus could infect cultured glioblastoma cells.

Introduction

Space-fill drawing of the outside of one Zika virus particle, and a cross-section through another as it interacts with a cell. The two main proteins of the viral envelope, the envelope proteins and membrane proteins, are shown in red and purple respectively. The lipid membrane of the envelope is shown in light lavender.The capsid proteins, in orange, are shown interacting with the RNA genome, in yellow, at the center of the virus. The cell-surface receptor proteins are in green, the cytoskeleton in blue, and blood plasma proteins in gold. Drawn by David Goodsell.
Space-fill drawing of the outside of one Zika virus particle, and a cross-section through another as it interacts with a cell. The two main proteins of the viral envelope, the envelope proteins and membrane proteins, are shown in red and purple respectively. The lipid membrane of the envelope is shown in light lavender. The capsid proteins, in orange, are shown interacting with the RNA genome, in yellow, at the center of the virus. The cell-surface receptor proteins are in green, the cytoskeleton in blue, and blood plasma proteins in gold. Drawn and copyright owned by David Goodsell.

Viruses enjoy a fearsome reputation. SARS-CoV-2 is only the latest infectious agent that has garnered attention by becoming a worldwide pandemic. Even the viral name suggests that SARS-CoV-2 was not the first of its type [SARS-CoV is the virus behind the severe acute respiratory syndrome (SARS) that spread worldwide in the early 2000s]. There are many different families of viruses (e.g., coronavirus for SARS-CoV-2 or lentiviruses for HIV-1) and each show a preference to the cell types they want to infect. By investigating the life cycle of viruses to better understand their mechanisms, researchers can discover new opportunities that may be exploited.

In 2015 and 2016, the virus that concerned health authorities was Zika virus (ZIKV). While this virus generally caused mild disease, the babies of women who were infected during pregnancy were at increased risk for microcephaly and other brain defects. These defects were traced back to Zika virus infecting nerve tissue, specifically, glial cells. This discovery provided an opportunity to explore how Zika virus might affect the brain tumor, glioblastoma multiforme (GMB), especially the glioblastoma stem cells (GSCs) that resist conventional treatment and contribute to the poor prognosis for GMB. Studies suggested that Zika virus infection prolonged survival in animal glioma models and selectively killed GSC with minimal effects on normal cells. In fact, the molecules used by ZIKV to enter cells were predominantly found on tumors, not normal cells. Knowing that the ZIKV envelope proteins prM and E provide the target specificity for glial cells, Kretchmer et al. wanted to explore if ZIKV envelope proteins substituted in lentivirus packaging systems would be able to enter glioblastoma cells.

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Ramping Up COVID-19 Testing with the Maxwell® HT Viral TNA Kit

COVID-19 testing with Maxwell HT

John Longshore admits that he was not a big Promega customer before the COVID-19 pandemic. His team uses a wide variety of suppliers to assemble the types of testing protocols needed to serve over 50 hospitals. However, when he began to face supply chain disruptions in early 2020, he needed a supplier he could depend on to support the rapid scale-up of COVID-19 testing, and Promega rose to the occasion.

“When we started working with Promega for bulk isolation reagents, our ask was, ‘Can you supply us with 15,000 isolation reagents per week?’” John says. “The answer was yes, and we have gotten everything we’ve asked for on the dates that it was promised.”

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Adenoviral Vector Vaccines for COVID-19: A New Hope?

The global war against the coronavirus that causes COVID-19 rages on, spearheaded by efforts to develop effective and safe vaccines. At the time of writing, over 100 COVID-19 vaccine clinical trials were listed in the clinicaltrials.gov database. Recent attention has focused on mRNA vaccines developed by Pfizer/BioNTech and Moderna. If licensed, they would become the first mRNA vaccines for human use.

Other vaccine development efforts are relying on more conventional techniques—using an adenoviral vector to deliver a DNA molecule that encodes the SARS-CoV-2 spike (S) protein. Examples of these adenoviral vector vaccines include the vaccines from Oxford University/AstraZeneca (the UK), Cansino Biologics (China), Sputnik V (Russia) and Janssen Pharmaceuticals/Johnson & Johnson (the Netherlands and USA).

sars-cov-2 coronavirus covid-19 infection with antibodies from a vaccine attacking the virus; several vaccines are in development including adenoviral vector vaccines
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