This news item is about: A new study with mice and humans, published June 21 in the journal Nature Communications, describes how an enzyme called ITK plays a crucial role in the development of Tr1 cells during an immune response. The enzyme offers an entry point for researchers to manipulate the development of Tr1 cells to enhance them to treat allergies, for instance, or block their development to treat viral and bacterial infections. “The more we understand about how these cells develop, the signals and pathways they use, the more likely we’ll be able to devise approaches to manipulate them,” said Avery August, professor of microbiology and immunology in Cornell’s College of Veterinary Medicine and the paper’s senior author. Weishan Huang, Ph.D. ’13, assistant research professor of microbiology and immunology, is lead author.