Snakes and lizards evolve minus key T cells

A U.S.-led international research group, including South Australian Museum, Flinders University and other experts, conclude it's likely that all squamates ( and lizards) are missing one set of T lymphocyte —paving the way for new research into what these T cells do in other animals, and how squamates compensate for this difference in immunology.

The article, "Skinks Make Do without γδ T Cells," published in the Journal of Immunology, compares the sleepy lizard genome to other reptiles and found it likely all squamates have lost one of the two major types of T cells over time.

"Out of all animals, it's rather odd snakes and lizards have survived without this complete set of disease-fighting cells, so this discovery could encourage further research on what these missing T cells actually do in vertebrates," says co-author Flinders University Professor Mike Gardner, an expert in the squamate skink Tiliqua rugosa (commonly known as sleepy, bobtail or shingleback lizard).

SA Museum senior researcher Dr. Terry Bertozzi, another author in the article, says the disappearance of certain T cells in squamates over time points also towards previously unexplored roles of other immune cells to compensate and protect against disease, inflammation and cancer.

Credit: Professor Mike Gardner (Flinders University)

Credit: Professor Mike Gardner (Flinders University)

Credit: Professor Mike Gardner (Flinders University)