Search: “t-cell”

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Covid-19: Do many people have pre-existing immunity?

October 12, 2020 / / 0 Comments

I have already talked about the mounting evidence supporting widespread T-cell immunity against SARS-CoV-2 (Covid-19).

This study on the British Medical Journal (Covid-19: Do many people have pre-existing immunity?) is interesting because it’s one of the few places where a similar situation from 2009 is recalled. In fact, in 2009 we experienced a casedemic with H1N1, that is, a growing number of cases which however did not lead to an actual high mortality rate. I quote:

Swine flu déjà vu

In late 2009, months after the World Health Organization declared the H1N1 “swine flu” virus to be a global pandemic, Alessandro Sette was part of a team working to explain why the so called “novel” virus did not seem to be causing more severe infections than seasonal flu.12

Their answer was pre-existing immunological responses in the adult population: B cells and, in particular, T cells, which “are known to blunt disease severity.”12 Other studies came to the same conclusion: people with pre-existing reactive T cells had less severe H1N1 disease.1314 In addition, a study carried out during the 2009 outbreak by the US Centers for Disease Control and Prevention reported that 33% of people over 60 years old had cross reactive antibodies to the 2009 H1N1 virus, leading the CDC to conclude that “some degree of pre-existing immunity” to the new H1N1 strains existed, especially among adults over age 60.15

The data forced a change in views at WHO and CDC, from an assumption before 2009 that most people “will have no immunity to the pandemic virus”16 to one that acknowledged that “the vulnerability of a population to a pandemic virus is related in part to the level of pre-existing immunity to the virus.”17 But by 2020 it seems that lesson had been forgotten.

Structural stability of SARS-CoV-2 3CLpro and identification of quercetin as an inhibitor by experimental screening - ScienceDirect

October 10, 2020 / / 0 Comments

Structural stability of SARS-CoV-2 3CLpro and identification of quercetin as an inhibitor by experimental screening – ScienceDirect
— Read on www.sciencedirect.com/science/article/pii/S0141813020339970

This is on top of Quercetin also being a Zinc ionophore, which helps increasing the amount of intracellular elemental zinc, which in turns inhibits replication of RNA viruses.

Immune cells for common cold may recognize SARS-CoV-2

October 8, 2020 / / 0 Comments

More on cross-reactive T-cell immunity.

They found that of the SARS-CoV-2 and “common cold” coronavirus fragments that were most similar (at least 67% genetic similarity) 57% showed cross-reactivity by memory T cells.

The evidence for pre-existing T-cell immunity against Covid-19 keeps piling up, hence the case for a much lower threshold for herd immunity becomes stronger. Conversely, the case for a vaccine becomes way weaker.

Children develop robust and sustained cross-reactive spike-specific immune responses to SARS-CoV-2 infection | Nature Immunology

December 26, 2021 / / 0 Comments

SARS-CoV-2 infection is generally mild or asymptomatic in children but a biological basis for this outcome is unclear. Here we compare antibody and cellular immunity in children (aged 3–11 years) and adults. Antibody responses against spike protein were high in children and seroconversion boosted responses against seasonal Beta-coronaviruses through cross-recognition of the S2 domain. Neutralization of viral variants was comparable between children and adults. Spike-specific T cell responses were more than twice as high in children and were also detected in many seronegative children, indicating pre-existing cross-reactive responses to seasonal coronaviruses. Importantly, children retained antibody and cellular responses 6 months after infection, whereas relative waning occurred in adults. Spike-specific responses were also broadly stable beyond 12 months. Therefore, children generate robust, cross-reactive and sustained immune responses to SARS-CoV-2 with focused specificity for the spike protein. These findings provide insight into the relative clinical protection that occurs in most children and might help to guide the design of pediatric vaccination regimens. SARS-CoV-2 infection is milder in children, but direct comparison with adults is rare. Here the authors show that immune responses are higher in children, retained for 12 months or longer and can neutralize Alpha, Beta and Delta variants.
— Read on www.nature.com/articles/s41590-021-01089-8

Comprehensive investigations revealed consistent pathophysiological alterations after vaccination with COVID-19 vaccines | Cell Discovery

October 30, 2021 / / 0 Comments

Large-scale COVID-19 vaccinations are currently underway in many countries in response to the COVID-19 pandemic. Here, we report, besides generation of neutralizing antibodies, consistent alterations in hemoglobin A1c, serum sodium and potassium levels, coagulation profiles, and renal functions in healthy volunteers after vaccination with an inactivated SARS-CoV-2 vaccine. Similar changes had also been reported in COVID-19 patients, suggesting that vaccination mimicked an infection. Single-cell mRNA sequencing (scRNA-seq) of peripheral blood mononuclear cells (PBMCs) before and 28 days after the first inoculation also revealed consistent alterations in gene expression of many different immune cell types. Reduction of CD8+ T cells and increase in classic monocyte contents were exemplary. Moreover, scRNA-seq revealed increased NF-ÎşB signaling and reduced type I interferon responses, which were confirmed by biological assays and also had been reported to occur after SARS-CoV-2 infection with aggravating symptoms. Altogether, our study recommends additional caution when vaccinating people with pre-existing clinical conditions, including diabetes, electrolyte imbalances, renal dysfunction, and coagulation disorders.
— Read on www.nature.com/articles/s41421-021-00329-3

B-cell immune memory against Covid-19

May 26, 2021 / / 0 Comments

I have posted many times about T-cell immunity against Covid-19. This new study (SARS-CoV-2 infection induces long-lived bone marrow plasma cells in humans), just published two days ago, confirms that “circulating resting memory B cells directed against the S protein were detected in the convalescent individuals” 11 months after first symptoms.

You can read more about it in this blog published on the Washington University School of Medicine website.

Quarter of people may already be immune to coronavirus – even though many have never been infected

November 19, 2020 / / 0 Comments

PHE researchers believe people with high levels of T-cells likely to have picked up immunity from coronaviruses like common cold
— Read on www.telegraph.co.uk/news/2020/11/19/many-could-immune-covid-despite-never-having-infected-study/

I’ve been mocked. I’ve been fact-checked by Facebook. Now it’s out in the open. The medical literature was clear. Cross reactive T cell immunity is the NORMALITY with coronaviruses.

Dr Michael Yeadon: “We appear to have forgotten that immunity after viral infection is the rule, not the exception.”

October 28, 2020 / / 0 Comments

On Twitter, British scientist Dr Michael Yeadon just gave a brief recap of some basic concepts regarding viral infections and immunity. Here’s the unroll:

Sometimes it’s useful to revisit basic concepts. We appear to have forgotten that immunity after viral infection is the rule, not the exception.

“In this chapter, we highlight the principal means by which the host achieves immunity following infection by viruses”.

“Table 27.1 presents an overview”.

“In humans, viral infections are rarely lethal, even if they are highly cytolytic to individual cells. Mortality commonly occurs when viruses jump species (eg. Ebola or HIV), when virus undergoes major antigenic change (i.e., influenza) or when host immunity is compromised”.

“Having entered the body, however, viruses encounter numerous innate defenses and activate the components of adaptive immunity. The latter usually assures that clinical disease, if not infection, will not become evident”.

“Viral infection induces an extensive array of defense mechanisms in the host. Innate defenses come into play to block or inhibit initial infection, to protect cells from infection, or to eliminate virus-infected cells, and occur well before the onset of adaptive immunity”.

Key Concepts: Principles of Antiviral Immunity
-Many human viral infections are successfully controlled by the immune system

-Certain emerging viruses may overwhelm the immune system and cause severe morbidity and mortality

-Other viruses have developed mechanisms to overwhelm or evade the immune system and persist

-Individuals with defects in innate or adaptive immunity demonstrate more severe viral infections

T-cell immunity is more important for control than antibody with many viral infections

-Antibody is important to minimize reinfection, particularly at mucosal sites

-Immune memory is often sufficient to prevent secondary disease, though not in all viral infection

Now this is basic stuff we’ve known for years. Especially the role of T-cells. This is a text book…

….that any undergraduate student might read. So when I hear numerous scientists & medics wringing their hands over how we’ll handle a common & garden coronavirus, I’m genuinely perplexed. “Like the last few, the endemic ones I was taught about, perhaps?” seems a good answer.

And this is why I’ve been forthright. I’ve not been making Nostradamus like predictions, just reading an undergraduate textbook.
Don’t let pseudo people fool you. It’s really not that special a virus; many of us had cross immunity to it before it arrived; very few are made…

…notably ill by it; I regret that those of advanced years, already beset usually by two life-limiting chronic illnesses were more likely to become seriously ill & a very small number died. It’s always been so at the end of life, as this chapter mentioned, when immune competence

…is reduced.

When you hear people setting way too much store about how long antibodies circulate, please know they’re mistaken. That’s not how immunity to most viruses is manifest. It’s mostly T-cells, as many of us have said for months.

Originally tweeted by Yardley Yeadon (@MichaelYeadon3) on October 27, 2020.

Pseudo-epidemics

October 18, 2020 / / 1 Comment

Yes, you read it. Pseudo-epidemics. They are a real thing.

Though I am scientist by training, I am not a medical scientist or anything closely related. But I remain a scientist. The scientific method that underpins all the sciences doesn’t change.

That’s what allowed to have a critical eye on all this pandemic business.

Now, all the recent posts on this blog are there to point out one simple thing: the Covid-19 pandemic has ended in May. What we’re seeing now is what many scientists and medical doctors are calling a casedemic.

In short, due to pre-existing T-cell immunity and the now endemic nature of the virus, the over-reliance on PCR testing is causing a overwhelming high number of false positives. These false positives are what they call asymptomatic people. Unlike what the people in the media tell you, the reality about these people is that they are not actually sick.

A few days ago I found out that there’s an established term to refer to what’s happening right now with SARS-CoV-2. It’s called a pseudo-epidemic.

A sample of articles that talk about this phenomenon:

From the latter I quote:

Given current definitions COVID-19 will never end. People will be dying of it forever, even if the virus disappears completely. Worse still, the system is locked in a series of feedback loops — if something causes test numbers to rise then so will case numbers, which in turn will cause a further increase in testing, causing the rise to continue, triggering local lockdowns and pointless evidence free rituals, until people get depressed and stop trying to do things causing numbers being tested to fall again.