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Covid Immune Response Study Revealing Potential Reason Some People Avoid Infection 

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In a new study from the University College London, scientists have discovered potential differences in immune responses that could reveal why some individuals avoid infection from Covid-19. 

The study, according to The Guardian, intentionally gave healthy adults a small nasal dose of Covid-19. The results showed that specialized immune cells in the nose could fight off the virus in the early stages of development before a full infection can form. 

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“These findings shed new light on the crucial early events that either allow the virus to take hold or rapidly clear it before symptoms develop. We now have a much greater understanding of the full range of immune responses, which could provide a basis for developing potential treatments and vaccines that mimic these natural protective responses,”  said Dr Marko Nikolić, senior author and honorary consultant in respiratory medicine. 

36 healthy adult volunteers without a previous history of having Covid and were unvaccinated were given a small dose of the virus through the nose. The study was done in 2021 at the height of the pandemic. 

16 of the volunteers were monitored specifically within the immune cells of the blood and the lining of the nose.

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“These participants were found to fall into three distinct groups: six people developed a sustained infection and became ill; three people became transiently positive but without developing a full infection; and seven experienced an ‘abortive infection.’ This subset never tested positive, but the tests showed they had mounted an immune response,” according to Hannah Devlin, a Science Correspondent for the Guardian. 

The abortive and transient groups had samples taken pre-exposure, and showed high activity levels in a gene called HLA-DQA2. 

“These cells will take a little bit of the virus and show it to immune cells and say: ‘This is foreign: you need to go and sort it out,’” said Dr Kaylee Worlock of UCL, first author of the study.

The study suggested that those with high levels of activity of the gene may have a more efficient immune response to Covid, however, they were not completely immune. 

The study could provide a basis for developing further and more effective treatments and vaccine options that can replicate the initial immune response that the cells in the nose provide.

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

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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.

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“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. 

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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.

Two Positive Covid Tests

New Study Shows Covid-19 Immunity Wearing Off In Patients Who Were Positive

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A study of hundreds of thousands of individuals in the United Kingdom suggests that immunity to the coronavirus is gradually wearing off in some individuals. Researchers sent out finger-prick tests to more than 365,000 randomly selected households in England and found that over the course of three months, Covid-19 antibody presence in the UK decreased by more than 26%. 

The research team behind the study recently spoke to the press about the findings that were taken after three-rounds of national surveillance. They sent out the tests 12, 18, and 24 weeks after the first peak of infections in England and observed a significant decline in detectable antibodies as time progressed. 

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“This is consistent with evidence that immunity to seasonal coronaviruses declines over 6 to 12 months after infection and emerging data that also detected a decrease over time in antibody levels in individuals followed in longitudinal studies.”

The study was published on Monday by Imperial College London and Ipsos Mori, a market research company. The initial data in the study was recorded in June, and found that 6% of individuals who took the tests had an antibody response to the coronavirus. By September that percentage had dropped down to 4.4%.

Antibodies are the proteins in your body that are created to fight infection. The type of test the group used to find these antibodies is called an IgG test, and they’re specially designed to only detect one kind of antibody; the coronavirus. This way if the test detects one of the other antibodies your body just naturally produces it won’t flag it for the study. 

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The results also confirm that asymptomatic individuals are likely to lose their detectable antibodies sooner when compared to symptomatic individuals who had more severe infections. Younger people who have recovered from the virus had a slower loss of antibodies compared to individuals aged 75 or older. 

It’s important to note also that even if an individual has Covid-19 antibodies in their system, it’s still unknown how immune an individual will be from potential reinfection and how long that immunity will last. The study also had its limits as well, as the samples weren’t taken from the same individuals every time, but instead just focused on the UK population in general. 

“This very large study has shown that the proportion of people with detectable antibodies is falling over time. It is essential that everyone continues to follow guidance to reduce the risk to themselves and others.”

Immune responses are being heavily studied as well throughout the world. This study is showing that the virus acts like a cold, in the sense that once an individual is infected they’re not immune from getting a cold again, however, they’re body will have a stronger immune response the next time they’re infected. Also like a cold, individuals with more robust immune systems will likely have a quicker response time and are more likely to carry antibodies after the fact. 

If anything, the researchers behind this study want the world to realize that if you get the virus and survive, you are not in the clear yet, and we all must remain diligent in the way we protect ourselves and our loved ones from potential infection.