California: Researchers have found rare naturally occurring T cells that are able to target a protein found in SARS-CoV-2 and a range of other coronaviruses.
The study is published in the ‘Cell Reports Journal’.
The findings suggested that a component of this protein, called viral polymerase, could potentially be added to COVID-19 vaccines to create a longer-lasting immune response and increase protection against new forms of the virus.
Most COVID-19 vaccines use a portion of a spike protein found on the surface of the virus to prompt the immune system to produce antibodies. However, newer types – such as Delta and Omicron – carry mutations in the spike proteins, which can make them less recognizable to immune cells and antibodies stimulated by vaccination. A new generation of vaccines would be needed to create a more robust and widespread immune response that would be able to outpace current forms and those that may arise in the future, the researchers said.
One way to accomplish this was to add a fragment of a different viral protein to the vaccines – one that is less prone to mutation than the spike protein and which would activate the immune system’s T cells. T cells are equipped with molecular receptors on their surfaces that recognize foreign protein fragments called antigens. When a T cell encountered an antigen that its receptor recognized, it replicated itself and produced additional immune cells, some of which immediately target and kill infected cells and others that remain in the body for decades. should come back sometime to fight the same infection.
The researchers focused on the viral polymerase protein, which is found not only in SARS-CoV-2, but also in other coronaviruses, including SARS, MERS and the common cold. Viral polymerases act as engines that the coronavirus uses to make copies of itself, enabling the infection to spread. Unlike spike proteins, viral polymerases are not likely to change or mutate, even as the virus develops.
To determine whether the human immune system has T cell receptors capable of recognizing viral polymerase, researchers exposed blood samples from healthy human donors (collected before the COVID-19 pandemic) to viral polymerase antigens. They found that some T cell receptors did indeed recognize the polymerase. They then used a method called CLint-Seq to genetically sequence these receptors. Next, the researchers engineered T cells to carry these polymerase-targeting receptors, which enabled them to study the ability of the receptors to recognize and kill SARS-CoV-2 and other coronaviruses.
So far more than 50 lakh people have died due to Kovid-19 worldwide. Current vaccines offer significant protection against serious disease, but as new, potentially more infectious forms emerge, researchers recognize that vaccines may need to be updated – and new UCLA The findings point to a strategy that may help increase protection and long-term immunity. Researchers are now conducting further studies to evaluate viral polymerase as a potential new vaccine component.
Pavlo Nesterenko, a UCLA graduate student, is the study’s first author; Related author is Dr. Owen Witte, who holds the presidency in developmental immunology UCLA Department of Microbiology, Immunology and He is the founding director emeritus of the Center for Molecular Genetics and Broad Stem Cell Research.
This research was supported by the Parker Institute for Cancer Immunotherapy, with the Ruth L. Kirschstein Institutional National Research Service Award. UCLA WM Cake Foundation COVID-19 research award program,
The study is published in the ‘Cell Reports Journal’.
The findings suggested that a component of this protein, called viral polymerase, could potentially be added to COVID-19 vaccines to create a longer-lasting immune response and increase protection against new forms of the virus.
Most COVID-19 vaccines use a portion of a spike protein found on the surface of the virus to prompt the immune system to produce antibodies. However, newer types – such as Delta and Omicron – carry mutations in the spike proteins, which can make them less recognizable to immune cells and antibodies stimulated by vaccination. A new generation of vaccines would be needed to create a more robust and widespread immune response that would be able to outpace current forms and those that may arise in the future, the researchers said.
One way to accomplish this was to add a fragment of a different viral protein to the vaccines – one that is less prone to mutation than the spike protein and which would activate the immune system’s T cells. T cells are equipped with molecular receptors on their surfaces that recognize foreign protein fragments called antigens. When a T cell encountered an antigen that its receptor recognized, it replicated itself and produced additional immune cells, some of which immediately target and kill infected cells and others that remain in the body for decades. should come back sometime to fight the same infection.
The researchers focused on the viral polymerase protein, which is found not only in SARS-CoV-2, but also in other coronaviruses, including SARS, MERS and the common cold. Viral polymerases act as engines that the coronavirus uses to make copies of itself, enabling the infection to spread. Unlike spike proteins, viral polymerases are not likely to change or mutate, even as the virus develops.
To determine whether the human immune system has T cell receptors capable of recognizing viral polymerase, researchers exposed blood samples from healthy human donors (collected before the COVID-19 pandemic) to viral polymerase antigens. They found that some T cell receptors did indeed recognize the polymerase. They then used a method called CLint-Seq to genetically sequence these receptors. Next, the researchers engineered T cells to carry these polymerase-targeting receptors, which enabled them to study the ability of the receptors to recognize and kill SARS-CoV-2 and other coronaviruses.
So far more than 50 lakh people have died due to Kovid-19 worldwide. Current vaccines offer significant protection against serious disease, but as new, potentially more infectious forms emerge, researchers recognize that vaccines may need to be updated – and new UCLA The findings point to a strategy that may help increase protection and long-term immunity. Researchers are now conducting further studies to evaluate viral polymerase as a potential new vaccine component.
Pavlo Nesterenko, a UCLA graduate student, is the study’s first author; Related author is Dr. Owen Witte, who holds the presidency in developmental immunology UCLA Department of Microbiology, Immunology and He is the founding director emeritus of the Center for Molecular Genetics and Broad Stem Cell Research.
This research was supported by the Parker Institute for Cancer Immunotherapy, with the Ruth L. Kirschstein Institutional National Research Service Award. UCLA WM Cake Foundation COVID-19 research award program,
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