What do the workings of red blood cells, ensuring breathable air for astronauts, and scraping soil off NASA’s Viking spacecraft have in common? The sharp thinking of biochemist Emmett Chappelle.
February is Black History Month in the US—a time to reflect on the contributions of African Americans in all fields and celebrate their accomplishments while recognizing the adversity they had to overcome in American society.
2021 also marks 30 years since the first firefly luciferase reporter vectors and detection reagents became available as products. There’s no better person to highlight this month than Emmett Chappelle, whose work with the luciferase reaction is still used for many applications today.
Screen Media. Cell phones. Social media accounts. If you are a parent, you have probably discussed rules of engagement with your children about these things. All of our modern social media platforms are designed to keep us engaged with them by showing us the latest post, the next video or the people now online. Work emails give us notifications when something arrives in our Inbox. Business software platforms like Microsoft Teams send us notifications whenever someone comments in a conversation we have ever been part of. There are many siren signals pulling us toward our screens.
Enter COVID-19, the flu-like illness caused by the SARS-CoV-2 virus that has already claimed the lives of 210,000 people in the United States, and leaving countless others permanently affected by other long-term health consequences. Spread by aerosol, COVID-19 is most dangerous in places where lots of people congregate in a small area, particularly if they are talking to each other. Consequently, office buildings are empty as many of us work or go to school remotely.
Before COVID-19, if I had a day full of meetings at work, I was running from conference room to conference room, two miles, uphill, in the snow between buildings. Now, a day full of meetings means sitting in front of a computer monitor, trying to figure out how I will get any kind of break between calls. The average number of steps recorded by my pedometer has decreased markedly since March when our remote work started.
Technology has been an incredible blessing during this pandemic—allowing us to continue to work and stay connected with friends and family. Technology is the only way that some people can connect with loved ones in long-term care facilities. It allows students to continue learning through remote classrooms and chats.
But what has been the effect of the increased time spent on screens during this pandemic?
Many cell biology researchers can name their department’s or institutions’s “cell culture wizard”—the technician with 20+ years of experience whose cell cultures are always free from contamination, exhibit reliable doubling rates and show no phenotype or genotype weirdness. Cell culture takes skill and experience. Primary cell culture can be even more difficult still, and many research and pharmaceutical applications require primary cells.
Yet, among the many causes of failure to replicate study results, variability in cell culture stands out (1). Add to the normal challenges of cell culture a pandemic that shut down cell culture facilities and still limits when and how often researchers can monitor their cell culture lines, and the problem of cell culture variability is magnified further.
Treating Cells as Reagents
A good way to reduce variability in cell-based studies is to use the thaw-and-use frozen stock approach. This involves freezing a large batch of “stock” cells, then performing quality control tests to ensure they respond appropriately to treatment. Then whenever you need to perform an assay, just thaw another vial of cells from that batch and begin your assay—just like an assay reagent! This approach eliminates the need to grow your cells to a specific stage, which could take days and introduce more variability.
Developing a vaccine that is safe, effective, easily manufactured and distributed is a daunting task. Yet, that is exactly what is needed in response to the COVID-19 pandemic.
Vaccine development, safety and efficacy testing take time. The mumps vaccine is thought to be the quickest infectious disease vaccine ever produced, and its development required four years from sample collection to licensing (2). However, there are many reasons to anticipate quicker development for a COVID-19 vaccine: Researchers are collaborating in unprecedented ways, and most COVID-19 scientific publications are free for all to access and often available as preprints. As of August 11, 2020, researchers around the globe have more than 165 vaccine candidates in development, 30 of which are in some phase of human clinical trials (1). The range of vaccine formulations available to scientists has expanded to include RNA and DNA vaccines, replication-defective adenovirus vaccines, inactivated or killed vaccines and subunit protein vaccines. Equally important is that vaccine developers and researchers have greater access to powerful molecular biology tools like bioluminescent reporters that enable quicker testing and development.
Celebrating the art of science is something the University of Wisconsin-Madison Cool Science Image Contest has been doing since its inception 10 years ago as part of The Why Files. The 2020 winning images include entries as diverse as videos of neural stem cells, eye-ball licking geckos and yes, even a picture of rock: actually a thin section of tractolite, an igneous rock composed of feldspar and olivine collected near Duluth Minnesota form the Proterozoic Mid-continent Rift. This image was collected by Natalie Betz, PhD, Associate Director of the UW-Madison Master of Science in Biotechnology program and her daughter Anya Wolterman, a recent graduate of Macalester College with degrees in Geology and Physics. Natalie has a long-time connection with Promega and the BioPharmaceutical Technology Center Institute, so we reached out to her to get the perspective of a contest entrant. Natalie is answering for both her and her daughter while her daughter is away doing some trail maintenance in the Rockies and is not available for comment.
Promega Connections: Why did you decide to enter the UW Cool Science Image contest?
Photo 51 is the now-famous X-ray diffraction picture that allowed Watson and Crick to crystalize centuries work of scientific study (from Mendel to Chargaff) into a viable structural model that explained how DNA could serve as the material of the gene. The photo was painstakingly produced by Dr. Rosalind Franklin, a contemporary of Watson and Crick. Although she and her colleague R.G. Gosling did publish their work in the same issue of Nature as the Watson and Crick paper (1,2), their work did not receive the same public accolades of that of Watson and Crick.
Women scientists have been contributing to our understanding of the world around us throughout history. On this 100th anniversary of Dr. Rosalind Franklin’s birth, we want to take a little time to recognize the work that women scientists are doing at Promega.
Our skin, respiratory system and gastrointestinal tract are continually bombarded by environmental challenges from potential pathogens like SARS-CoV-2. Yet, these exposures do not often cause illness because our immune system protects us. The human immune system is complex. It has both rapid, non-specific responses to injury and disease as well as long-term, pathogen-specific responses. Understanding how the immune response works helps us understand how some pathogens get past it and how to stop that from happening. It also provides key information to help us develop safe and effective vaccines.
The immune response involves two complementary pathways: Innate Immunity and Adaptive Immunity. Innate immunity is non-specific, rapid and occurs quickly after an injury or infection. As a result of the innate immune response, cytokines (small signaling molecules) are secreted to recruit immune cells to an injury or infection site. Innate immunity does not develop “memory” of an antigen or confer long-term immunity.
The immune response involves to complementary pathways: Innate Immunity and Adaptive Immunity.
Unlike innate immunity, adaptive immunity is both antigen-dependent and antigen-specific, meaning that adaptive immune response requires the presence of a triggering antigen—something like a spike protein on the surface of a virus. The adaptive immune response is also specific to the antigen that triggers the response. The adaptive immune response takes longer to develop, but it has the capacity for memory in the form of memory B and T cells. This memory is what enables a fast, specific immune response (immunity) upon subsequent exposure to the antigen.
Monitoring the use of performance-enhancing substances among athletes is complex and the requirements for tests and assays that detect use of such substances have changed significantly over the last few decades.
The haematological (blood) module of Athlete Biological Passport was adopted December 1, 2009 (ABP) by the World Anti-Doping Agency. The module sets out standard protocols to monitor doping of professional athletes by looking at changes in biological parameters, without relying on the detection of illegal compounds in body fluids. Such biological methods eliminate the need to develop and validate a test to detect every new compound that can be used for doping. The current version of the ABP, adopted in 2014, also adds monitoring of certain steroid use indicators from urine samples.
Blood doping which aims at increasing red blood cells so that more oxygen can be transported to muscles to increase stamina or performance is particularly difficult to detect. There are typically three ways that it is accomplished: use of erythropoietin (EPO) or synthetic oxygen carriers and blood transfusions. While transfusions of large volumes of blood or use of EPO can be detected, microdosing EPO or transfusing smaller volumes of packed red blood cells is much harder to detect.
Nicolas Leuenberger and colleagues at the Swiss Laboratory for Doping Analysis have developed a method to detect blood doping. In addition to addressing the detection of blood doping, his laboratory is also concerned about easing the transport and storage requirements for samples and ensuring that sample collection does not adversely affect athlete performance.
Improving Collection and Storage of Blood Samples
Because sample collection and storage are so critical to accurate test results, any new assays developed to detect blood doping benefit from ease of collection and storage. The Leuenberger laboratory investigated the use of the TAP™ Push Button collection device, which is billed as a simple method for blood collection that is easy to use and eliminates the need for painful needle sticks or finger pricks that can affect athlete performance. After TAP collection, 20µl of blood from the device was placed on to filter paper and dried (dried blood samples; DBS), which are much easier to store and transport from collection site to laboratory.
An RNA Biomarker for Blood Doping
Blood withdrawal and autologous transfusion or recombinant human EPO injection stimulate erythropoiesis and immature red blood cells can be distinguished based on their gene expression profiles. One of the genes that is expressed by immature red blood cells is aminoleuvulinate synthase 2, a gene that encodes an enzyme ALAS2 involved in the synthesis of heme, a pathway active during RBC maturation. RNA transcripts are unstable and tend to degrade rapidly, so isolating linear RNA transcripts from a collected sample can be difficult. However circular RNAs (circRNAs) are a class of RNA molecule produced by the backsplicing of pre-mRNAs that are high in abundance, quite stable and maintain cell-type specific expression. The Leuenberger laboratory developed a method for measuring the linear and circular forms of ALAS2 RNA in DBS to monitor erythropoiesis.
One of the greatest challenges in developing this protocol was achieving efficient RNA extraction from only 20ul of dried blood. Leuenberger and his colleagues adopted a two-step purification; beginning with a phenol:chloroform extraction on the DBS followed by a further purification on the Maxwell® RSC automated instrument, using the Maxwell RSC miRNA Serum and Plasma kit. Switching from a manual to an automated method for the second step was crucial. It reduced chances of contamination as well reduced pipetting errors, without compromising good quality and yield of RNA therefore contributing to assay reproducibility. To normalize volumes within the blood spot, the protocol uses RNA produced by housekeeping genes. The work to automate the assay has been published in Bioanalysis.
This protocol is being tested to see if microdosing of EPO or small transfusions can also be detected by monitoring ALAS2 RNA expression in DBS. The Swiss laboratory of Doping Analysis is also in the process of developing a method to detect gene doping by isolating plasmid DNA from whole blood samples, using the Maxwell® RSC.
Additionally, the collection and storage methods used have implications for the clinic, especially for patients that need routine blood monitoring. The ability to isolate circular RNAs shows promise in forensic applications to identify body fluids.
Want to know more about how the Maxwell® RSC can give you the freedom to focus on the work that interests you the most? To learn more, click here.
Laboratories can be crowded places. We are used to working around other people, tossing ideas back and forth. Dark rooms, cold rooms and large equipment spaces are often shared by several labs. Some labs have shut down completely in response to the COVID-19 pandemic; others, especially those labs doing research around coronavirus biology, testing and detection and drug development are running continually. For those labs, maintaining the recommended 6-foot (2m) distance to help stem the coronavirus pandemic isn’t easy.
At Promega our operations, quality assurance, applications and research and development labs are up and running—focused on providing as much support as possible to our partners who are studying, diagnosing and developing treatments for COVID-19. At the same time, we are maximizing the safety of our employees. Here are a few ways we have found to maintain critical distances in our laboratory that might help your lab group stay productive and safe too.
This blog was written with much guidance from Jennifer Romanin, Senior Director IVD Operations and Global Service and Support, and Ron Wheeler, Senior Director, Quality Assurance and Regulatory Affairs at Promega.
A Trip Down Memory Lane
Back in the day when we all walked two miles uphill in the snow to get to our laboratories, RNA and DNA extraction was a home-brew experience. You made your own buffers, prepped your own columns and spent hours lysing cells, centrifuging samples, and collecting that fluorescing, ethidium bromide-stained band of RNA in the dark room from a tube suspended over a UV box. Just like master beer brewers tweak their protocols to produce better brews, you could tweak your methodology and become a “master isolater” of RNA. You might get mostly consistent results, but there was no guarantee that your protocol would work as well in the hands of a novice.
Enter the biotechnology companies with RNA and DNA isolation kits—kits and columns manufactured under highly controlled conditions delivering higher quality and reproducibility than your home-brew method. These systems have enabled us to design ever more sensitive downstream assays–assays that rely on high-quality input DNA and RNA, like RT-qPCR assays that can detect the presence of a specific RNA molecule on a swab containing only a few hundred cells. With these assays, contaminants from a home-brew isolation could result in false positives or false negatives or simply confused results. Reagents manufactured with pre-approved standard protocols in a highly controlled environment are critical for ultra sensitive tests and assays like the ones used to detect SARS-CoV-2 (the virus that causes COVID-19).
The Science of Manufacturing Tools for Scientists
There are several criteria that must be met if you are
producing systems that will be sent to different laboratories, used by
different people with variable skill sets, yet yield results that can be
compared from lab to lab.