Posts

T-Cells From Common Colds Could Help Create A ‘Variant-Proof’ Covid Vaccine 

According to new research from the Imperial College London, T-cells that are generated as part of the body’s natural immune response to the common cold could help protect against serious Covid-19 illness, and potentially lead to a vaccine that would be effective against new variants of the virus. 

The recently published study began back in September 2020 and followed 52 household contacts of people who had tested positive for Covid-19. The data showed that 26 people who were exposed to the virus, but didn’t show any symptoms, had significantly higher cross-reactive T-cells, which were generated by previous common colds.

Embed from Getty Images

“The conclusion should not be that if you’ve had a common cold you don’t need to worry about contracting COVID-19. This is so for a number of reasons, including that not all colds are caused by coronaviruses, and T-cells’ ability to fight off symptomatic infections wanes over time,” Professor Aljit Lalvani, one of the authors of the study, explained. 

“What the study tells us is that there is a mechanism, a natural mechanism of natural protective immunity, that is triggered by previous common cold coronavirus infections, so we want to harness that naturally occurring protective immunity to develop better vaccines.”

Lalvani explained that the majority of the current Covid-19 vaccines out there specifically target the virus’ spike protein, as that’s the part that attacks healthy human cells. The vaccines then cause the body to produce antibodies and T-cells that can respond to that protein. 

Embed from Getty Images

He then explained how the new research found that T-cells created after a common cold caused by other coronaviruses (which are common) can attack a type of protein that remains similar among all the known Covid-19 variants. These proteins are what give the virus the ability to replicate itself. 

“The fact that the T-cells can attack the internal proteins of each of these related COVID-19 variants means that they give what’s called a broad cross-protection. That’s in sharp contrast to the surface spike protein, which is the target of antibodies induced by vaccines.”

“Clearly, SARS-CoV-2 is under huge, intense pressure in the global population because most people now have these antibodies, whether induced by vaccination or infection, so the virus is trying naturally to evade that immunity through mutation, and that’s why Omicron has such a high number of mutations in the spike protein. But the internal proteins are relatively unchanged,” Lalvani stated. 

“We’re very fortunate to have found what immunologists refer to as the ‘Holy Grail,’ so we’re keen for people to understand this and to see that, at last, there is a path towards dealing with future variants.”

“This is now a definitive green light to move forward and develop a T-cell inducing vaccine to internal core proteins, which should protect against current and future variants,” he said.

Senior Couple

Super Immune Cells Found In World’s Oldest People

If you know someone who has defied the laws of time and is now living as a 110 year old or older, scientists may have figured out why these individuals are able to remain alive and normally functioning for so long. The term for someone who lives to 110 years old is known as a “supercentenarian,” according to a research study on these individuals performed by scientists in Japan.

“[Supercentenarians] have higher-than-typical concentrations of a particularly rare type of T helper cell in their blood. These immune cells might protect the oldest of the old against viruses and tumors, leaving them in remarkably fine health throughout their long life spans. The key will be to understand what is [the cells’] their natural target, which may help to reveal what is needed for a healthy, long life,” study co-authors Kosuke Hashimoto, Nobuyoshi Hirose and Piero Carninci wrote in a joint email to Live Science Magazine.

Embed from Getty Images

The three co-authors who wrote and performed this study all are based in Japan. They are the first group of scientists to actually analyze the immune cells of supercentenarians. Life expectancy and longevity rates are generally very high in Japan so it makes sense that this is the location where the study occurred, as it most likely offered the greatest pool of subjects to be involved. However, they all noted that even in Japan, where life expectancy is on average 81 years for men and 87 years for women (based on government statistics) individuals who live to or past 110 years old are quite rare. The same government statistics/census data showed that there are, on average, 61,000 people over the age of 100 living in the country, but only 146 of that 61,000 are 110 or older. 

With such a small pool of individuals to choose from for this study, it obviously made the research difficult. According to the co-authors in the study, they used a group of seven supercentenarians and five control participants to compare and contrast the data. The control participants ranged in age from 50 to 80. The researchers focused on the immune cells in the subjects blood samples. 

“The scientists then used an advanced method called single-cell transcriptomics to find out what each of the immune cells was doing — individually. This method measures the messenger RNA produced by the hundreds of thousands of genes within a cell. Messenger RNA is the go-between that translates the genetic instructions of DNA to the nucleus of the cell, which uses those instructions to build proteins. By essentially reading the messages of the messenger RNA, researchers can determine the activities of each cell, effectively identifying it and its function,” according to Live Science

Embed from Getty Images

What they found through this process was quite astounding. Not only did the samples taken from the seven supercentenarians indicate that each subject had more than 40,000 immune cells present in their bloodstream, but compared to the control group, that’s around an average of 20,000 more cells than the younger subjects. The main piece of recorded data that surprised a lot of the researchers, however, was the presence of an immune cell group known as “CD4 CTL.” This grouping is basically a type of helper T cell (the cells in our immune system that attack viruses) that directly attacks and kills other cells almost immediately, according to the study

Why this finding is so surprising is because CD4 cells in general are quite rare, and when they are present in our immune systems they don’t really fight other cells, that’s typically just the T cell’s job. These cells normally act like “nerves” for our immune system and simply communicate with other cells when negative foreign bodies have entered the bloodstream, and then they let the T cells do their job and destroy them. However, it’s already been known that these cells have the ability to attack other cells, they just typically don’t. This abundance of immune cell soldiers could lead us to understanding how once an individual passes a certain point in aging that they lead healthy lives until they eventually pass from old age. 

Due to the small sample size of recorded data, the researchers can’t make a concrete connection between these cells and the longevity of life in the subjects, however, it’s a great start. These cells in the past have been proven to kill tumor cells in mice subjects, so it’s a great indication at the possibility of how supercentenarians are even a real thing. For now, the group will continue their research in hopes to unlock more answers about our bodies complex immune systems.