New research led by Murdoch Children’s Research Institute and Federation University Australia reveals how gamma delta T cells develop and produce an immune response. Researchers uncovered the role the thymus gland plays in creating and training cells. The discovery could lead to the development of more preventive treatments against infection and disease.
The study is published in Science immunology in an article titled, “A three-stage developmental pathway for human Vγ9Vδ2 T cells within the postnatal thymus.”
“Vγ9Vδ2 T cells are the largest population of γδ T cells in adults and can play important roles in providing effective immunity against cancer and infection,” wrote the researchers. “Many studies have suggested that peripheral Vγ9Vδ2 T cells are derived from the fetal liver and thymus and that the postnatal thymus plays little role in the development of these cells. More recent evidence suggested that these cells may also develop postnatally in the thymus. Here, we used high-dimensional flow cytometry, transcriptomic analysis, functional assays, and precursor-product experiments to define the development pathway of Vγ9Vδ2 T cells in the postnatal thymus.”
Associate professor Dan Pellicci, PhD, said by understanding the function of these cells, they could be harnessed to help prevent cancer and highly infectious diseases such as COVID-19, Strep A, and tuberculosis.
The study involved samples donated to the Melbourne Children’s Heart Tissue Bank from heart surgery patients up to 16 years old. The researchers observed the role of “gamma delta T cells” within the thymus gland.
Pellicci said the study showed for the first time how this organ produced these infection-fighting immune cells.
“We have large numbers of these specialized cells in our blood and tissues, which accumulate as we become adults. Until our study, it was unclear how these cells develop in the body,” he said.
“We have shown how these cells are trained over three stages, similar to receiving a primary, secondary, and tertiary education, and fully formulate within the thymus. Following this education, the cells are ready to enter the rest of the body and are completely capable of fighting infections.”
“Many experts assumed that after birth, the thymus played little role in the development of these cells as we age, but we now know this little unsung organ helps the body prepare for a lifetime of good health,” he said.
“The more we know about these cells the greater the likelihood of unlocking new ways to treat infectious diseases and cancer.”