Multiple battles are being fought in the war against the SARS-CoV-2 coronavirus that causes COVID-19. Currently, there are nearly 3,000 clinical trials listed in the World Health Organization (WHO) database, either underway or in the recruiting stage, for vaccines and antiviral drugs. Two recent announcements of data from phase 3 vaccine trials, by Pfizer/BioNTech and Moderna, have offered some hope for global efforts to fight the pandemic. At the time of writing, Pfizer and BioNTech had submitted an application for emergency use authorization (EUA) to the Food and Drug Administration (FDA), and Moderna had planned to do so shortly.
Both vaccines are mRNA-based, as opposed to most conventional vaccines against established diseases that are protein-based. Typically, the key ingredient in viral vaccines is either part of an inactivated virus, or one or more expressed proteins (antigens) that are a part of the virus. These protein antigens are responsible for eliciting an immune response that will fight future infection by the actual virus. Another approach is to use a replication-deficient viral vector (such as adenovirus) to deliver the gene encoding the antigen into human cells. This method was used for the coronavirus vaccine developed by Oxford University in collaboration with AstraZeneca; phase 3 interim data were announced on the heels of the Pfizer/BioNTech and Moderna announcements. All three vaccines target the SARS-CoV-2 spike protein, because it is the key that unlocks a path of entry into the host cell.
If you are the “family scientist” you may find yourself answering questions about things like antibodies, immunity and serology from friends and family curious about the COVID-19 pandemic and all of the news they are seeing. Whether you are an oceanographic cartographer or a seasoned immunologist, we hope that this infographic about antibody testing helps.
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.
Over a hundred years ago William B Coley, the “Father of Immunotherapy”, discovered that injection of bacteria or bacterial toxins into tumors could cause those tumors to shrink. The introduction of bacteria had the side-effect of stimulating the immune system to attack the tumor. The field of cancer immunotherapy research—which today includes many different approaches for generating anti-tumor immune responses—originated with these early experiments.
Use of bacteria is one way to stimulate the immune system to attack cancer cells, others include use of cytokines, immune checkpoint blockades and vaccines. This Nature animation provides a simple overview of these methods.
There’s likely a percentage of the readers of this blog who, if presented with a photo montage of George Clooney, Brad Pitt, Javier Bardem, Daniel Craig, Denzel Washington, Ryan Gosling and other celebrity heartthrobs, might have to take a moment (or several) just to sit back, breathe deeply and appreciate the view. And who could blame us? They’re manly men, all. Easy on the eyes, fairly dripping with testosterone, make our hearts go pitter-pat, maybe make our loins jump just a little with subconscious fantasies of beautiful Clooney babies. What? It’s only natural! It’s biology!
But a recent research effort, published in the February 21 edition of the journal Nature Communications, asserts that our twitterpation (or Brad Pitterpation, as it were) may not be so much for these guys’ handsome faces, strong jawlines, broad shoulders, six-pack abs, that spot in the crook of their neck that probably smells really good…