By Alistair Smout

LONDON (Reuters] – A study by Imperial College London found that high levels of T-cells derived from common cold coronaviruses could provide protection against COVID-19. It was published Monday and may inform strategies for developing second-generation vaccines.

The complex nature of immunity against COVID-19 makes it difficult to understand. There is some evidence that antibody levels have declined six months after the vaccination. However, there are other indications that T-cells may play an important role in protecting you.

In order to find out if the household contacts were infected, this study examined levels of reactive T-cells from previous common illnesses in 52 people who had received positive COVID-19 results.

According to the study, 26 of them had significantly lower levels than infected people. Imperial could not be reached for comment on how long T-cell protection would last.

“We found that high levels of pre-existing T cells, created by the body when infected with other human coronaviruses like the common cold, can protect against COVID-19 infection,” study author Dr Rhia Kundu said.

Nature Communications published the findings in Nature Communications. The study authors suggested that vaccine manufacturers could target the SARS-CoV-2 internal proteins, which were targeted by T-cells.

COVID-19 vaccines currently target spike protein. This mutates frequently, creating Omicron variants that reduce the effectiveness of vaccines for symptomatic infections.

Professor Ajit Lavi, co-author, stated that “in contrast, internal proteins targeted in the protective T cells we identified mutate less.”

They are therefore highly conserved among the different SARS-CoV-2 variations, including Omicron. These internal proteins are conserved and would be a part of any new vaccines. This will result in broad protective T cells responses, which should help protect against future SARS-CoV-2 variations.