In recent news, there are concerns about the newly discovered COVID variant named Omicron. Preliminary evidence suggests an increased risk of reinfection with this variant, as compared to other variants of concern. Scientists are hopeful that T cells could provide some immunity to COVID-19, even if antibodies become less effective at fighting the disease.

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Killer T Cells in Action

Along with antibodies, the human body’s immune system produces a plethora of T cells which target viruses. Helper T cell’s stimulate killer T cells, macrophages, and B cells to make immune responses. T cells do not prevent infection because they kick into action only after a virus has infiltrated the body. But, they are important for clearing an infection that has already started. If killer T cell’s are able to kill virus-infected cells before they are able to spread to from the upper respiratory tract, it will affect how you feel and will be the difference between a mild infection and a severe one.

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SARS-CoV-2

Studies by Sette and his colleagues have shown that people who have been infected with SARS-CoV-2 typically generate T cells that target at least 15–20 different fragments of coronavirus proteins. But, the protein particles that are targeted vary from person to person. This means that a variety of T cells will be generated, making it difficult for the virus to mutate in attempt to escape cell recognition. Research suggests that most T-cell responses to COVID variations or previous infection do not target regions that were mutated in recently discovered variants. If T Cells remain active within your immune system against specific variants, they might protect against severe diseases.

Ultimately, in my opinion, this is extremely important since researchers have been analyzing clinical-trial data for several coronavirus vaccines in attempt to find clues as to whether their effectiveness fades in the face of new emerging COVID variants such as Omicron. As of now, coronavirus vaccine developers are already looking at ways to develop next-generation vaccines that stimulate T cells more effectively. Antibodies only detect proteins outside cells, and many coronavirus vaccines target spike proteins, located on the surface of the virus. Since spike proteins are liable to change, it may be prone to mutating and raising the risk that emerging variants will be able to evade antibody detection. T cells, on the other hand, can target viral proteins located inside infected cells, and some of those proteins are very stable. This raises the possibility of designing vaccines against proteins that mutate less frequently than spike proteins, and incorporating targets from multiple proteins into one vaccine.

Biotechnology firm Gritstone Oncology of Emeryville, California, is designing an experimental vaccine that incorporates the genetic code for fragments of several coronavirus proteins known to elicit T-cell responses, as well as for the full spike protein, to ensure that antibody responses are robust. Clinical trials are due to start in the first quarter of next year. If approved, this vaccine could revolutionize how we approach the creation and experimentation of COVID vaccines in the future.