T cells may be dealing the killer blow to virus | Economic Times

Mumbai: Antibodies alone are not enough to protect an individual from the coronavirus that causes Covid-19, and what could help more in fighting the disease is a strong T cell response, a new study from California-based La Jolla Institute for Immunology has shown.The researchers said their new study was in line with other data that showed the T cells and the killer T cell had a bigger part to play in protecting an individual against the SARS-Cov2 virus than antibodies.The implication of this study will also be on vaccine development, which needs to show not only high antibody titers, but overall immune response, including T cells.78179320Antibodies are the first form of defence against a pathogen. When the body is attacked by a virus, the immune system produces antibodies in the blood that put up a defence against the intruder. When the body doesn't generate antibodies, it depends on T cells along with the B white-blood cells to fight against the intruder — these are called an adaptive immune system.“A weak or uncoordinated immune response, on the other hand, predicts a poor disease outcome. The findings suggest that vaccine candidates should aim to elicit a broad immune response that include antibodies, helper and killer T cells to ensure protective immunity.,” Shane Crotty, who co-led the study with Alexandro Sette, said, adding: “Although it is also plausible that T cell responses against this virus are important in both cases.”The study, which was published in the medical journal Cell, also throws perspective on why SARS-Cov2 hurts those above 60 years of age more — with age, the body’s ability to generate naïve T cells goes down, which makes it difficult to put a defence against the infection.The researchers studied blood samples from 50 people diagnosed with Covid-19 and looked for the entire range of immune responses generated by these patients.