Many Have A Fallacy That SARS-CoV-2 Does Not Target Nor Impair CD4 T Cell Function Nor Damage Them! It Does!
: There is a prevailing fallacy that SARS-CoV-2 does not affect CD4 T cells unlike HIV but in reality, it does…only that it does not do it the same way as HIV.
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It is already accepted that SARS-CoV-2 is causes lymphopenia (also called lymphocytopenia).. a disorder in which the blood doesn't have enough white blood cells called lymphocytes including low levels of CD4 and CD8 T cells.
Studies have also showed that SARS-CoV-2 causes impaired T Cell responses.
However, many are not aware that SARS-CoV-2 can directly infect the CD4 cells to cause impairment or damage or that the SARS-CoV-2 spike proteins can also prevent recognition by the CD4+ T cells.
There are already so many studies that have shown that SARS-CoV-2 virus can affect the CD4 T Cells in a variety of ways and in fact it is still evolving to do so more effectively! Past COVID-19 News
reports had mentioned early warnings about this in 2020.
An updated study published in early 2023 by Brazilian researchers who were the second group to sound the warnings in 2020 shows that show that SARS-CoV-2 is able to infects human CD4+ T helper cells, but not CD8+ T cells, and is present in blood and bronchoalveolar lavage T helper cells of COVID-19 infected individuals.
The study team demonstrated th
at SARS-CoV-2 spike glycoprotein (S) directly binds to the CD4 molecule, which in turn mediates the entry of SARS-CoV-2 in T helper cells. This leads to impaired CD4 T cell function and may cause cell death. SARS-CoV-2-infected T helper cells express higher levels of IL-10, which is associated with viral persistence and disease severity. Thus, CD4-mediated SARS-CoV-2 infection of T helper cells may contribute to a poor immune response in COVID-19 patients.
We have also covered so many other studies showing how SARS-CoV-2 affects the CD4 Cells.
The Chinese researchers which were actually to sound the alarms in early 2020 strangely retracted their studies and have since then concealed and also classified all information with regards to detailed studies involving SARS-CoV-2 and CD4, CD8 and immune impairment or immune dysregulation studies while interestingly they have been stockpiling certain drugs and APIs (active pharmaceutical ingredients in the last 5 months! I am not mentioning these drugs and APIs but some due diligence online and many of you can figure out what they are!)
Researchers from University of Birmingham in December last year warned that mutations of the SARS-CoV-2 spike proteins were leading to impaired epitope-specific CD4+ T cell recognition!
The study team isolated 159 SARS-CoV-2-specific CD4+ T cell clones from healthcare workers previously infected with wild-type SARS-CoV-2 (D614G) and defined 21 epitopes in spike, membrane and nucleoprotein. Lack of CD4+ T cell cross-reactivity between SARS-CoV-2 and endemic beta-coronaviruses suggested these responses arose from naïve rather than pre-existing cross-reactive coronavirus-specific T cells. Of the 17 epitopes located in the spike protein, 10 were mutated in VOCs and CD4+ T cell clone recognition of 7 of them was impaired, including 3 of the 4 epitopes mutated in omicron.
While at that time, their study findings indicated that broad targeting of epitopes by CD4+ T cells likely limits evasion by the then VOCs, the continued evolution of the SARS-CoV-2 sub-lineage have not been properly monitored in regards to this area and there is a very high possibility that many of these new mutations are able to evade CD4+ T cell immunity.
Studies have also showed that SARS-CoV-2 could affect T Cell maturation including that of CD4 cells.
Studies have already showed that the new Omicron variants are driving impaired T cell immunogenicity including that of the CD4 T Cells and leading to enhanced immune escape.
In fact, more urgent studies are needed on the recent SARS-CoV-2 variants that have emerged in the last 8 weeks with mutations on both the spike and N proteins in terms of potential enhanced damage they can do with regards to the CD4 cells and also ways they can impair T cell responses.
I have already sounded a crazy hypothesis on Twitter and a few studies underway should reveal some interesting findings.
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