T cells use two pathways to recognize many different parts of a virus.
The T-cell response is key to an effective long-term immune response to a virus or a vaccine. What many may not realize is that T cells do not recognize an entire virus protein. T cells recognize little pieces of virus proteins displayed on special protein complexes called major histocompatibility complex (MHC). In this short video (no sound), I explain how infected cells or innate immune cells that take up viruses can display these little pieces of virus proteins, called antigens, to stimulate T cells.
The genes in…
There appears to be quite a bit of confusion about what immunity means for the COVID-19 vaccines that are in use in the U.S. and Europe. These are the 2 mRNA-based vaccines and the DNA-based vaccine:
3 Vaccines Protect against COVID-19.
Clinical trial results from 3 vaccines show that the vaccines have good efficacy. This means that they protect the people who receive the vaccine from getting severe COVID-19. Two of the vaccines are based on a new technology that has not been used before in approved vaccines. The technology is new, however, it is not completely different from some other vaccine technologies. The two vaccines deliver instructions (in the form of nucleic acid) for your own cells to make a protein that the virus makes, so your body will recognize when the virus is present and prevent it from infecting…
Too much histamine or prostaglandin D2 signaling or too little interferon signaling lead to increased risk for severe COVID-19.
An imbalanced immune response appears to be the key to whether a person develops severe COVID-19 with pneumonia and other complications such as coagulopathy (excessive formation of blood clots), impaired kidney function, neurological issues, and heart complications. Multiple mechanisms likely contribute to the variability in the immune response within the population and determine whether a person has asymptomatic disease, mild disease, or severe disease with potentially fatal complications. …
An available medication used in Japan for allergies could be an effective treatment for COVID-19 in the elderly and overweight.
Obesity is associated with a pro-inflammatory state. Aging is also associated with changes in the immune system. Could there be a common change in inflammatory mediators in both of these populations that contributes to the increased risk of developing severe COVID-19?
Dr. Ajay Gupta, MD, MBBS (Chief Scientific Officer of Rockwell Medical, Inc) thinks so. He thinks the connection is prostanoids, in particular prostaglandin D2 and thromboxane A2. Prostaglandin D2, in particular, increases with age and obesity, providing a potential molecular link between these two conditions and the risk of developing severe COVID-19.
It only takes one person to turn a social interaction bubble into a germ circle.
As the cold weather comes, I am beginning to plan how to socialize safely. It will be harder to do outside visits or visits with the doors and windows open to keep ventilation high. This means I need to think more carefully about who is inside my social interaction bubble. Each household that is part of the circle extends my circle.
It rapidly becomes a complex diagram of overlapping circles. It only takes one person in any of these overlapping circles to contract SARS-CoV-2, with or without symptoms of COVID-19, and the virus can get into my circle.
So, as…
Genetic variations and autoantibodies that compromise interferon signaling explain ~14% of severe COVID-19 cases.
As researchers evaluate patients that develop severe COVID-19, the disease caused by the coronavirus SARS-CoV2, they are discovering answers to why some people become so critically ill and others do not. A pair of papers in Science by international teams of scientists led by Jean-Laurent Casanova reports reasons for why ~14% of severe cases of COVID-19 occur. Importantly, this information is clinically useful and will help screen at-risk individuals, prioritize vaccination, and treat patients. Additionally, these findings support a key theory regarding why COVID-19 shows so much variability: Interferon signaling varies within the population.
Genetic Variation that Compromises Interferon Signaling
The engineered protein vaccine VLA15 induces multiple antibodies in a Phase II trial and has the potential to provide protection against the different bacteria that cause Lyme disease in North America and Europe.
Lyme disease is caused by bacteria ( Borrelia burgdorferi, Borrelia afzelii, and Borrelia garinii) that are delivered by a bite from an infected tick. Although antibiotics can treat Lyme disease, some people do not realize they have been infected. The longer a person waits to receive treatment, the worse the outcome is likely to be. Thus, an effective vaccine would be tremendously helpful for people in regions where the disease-carrying ticks are common. Indeed, the Centers for Disease Control (CDC) in the U.S. estimates ~300,000 people are infected annually.
Valneva is a company that has completed Phase II clinical trials…
CDC guidelines do not mean we know how long COVID-19 immunity lasts.
Lots of confusion out there today. Yesterday, I saw a tweet in the news part of Twitter titled, “CDC says recovered COVID-19 patients will have immunity for about three months.”
Fear of the unknown and comfort with risk
For some, the virus is just a part of the risk of life and nothing to be terribly concerned about; for others, the virus is terrifying and any risk of exposure is too much.
Several aspects of the pandemic foster fear, especially in people who are risk averse and uncomfortable with the unknown:
- A fraction of infected people will become desperately ill or even die, but we have no way of knowing who those people are in advance.
- No universally effective treatment is available for those who will become severely ill with COVID-19, so we don’t know if treatment will…
