T lymphocytes differentiate from a naive state to an effector state.
The latter is characterized by the ability to secrete large amounts of potent molecules, termed cytokines, that collectively orchestrate and focus the attack against pathogens. Different types of pathogenic organisms require different types of immune responses, that are defined by the spectrum of cytokines produced by the effector T lymphocytes. The most characterized effector subsets, termed type 1 and type 2 immunity, are associated with host defense against intracellular and intestinal pathogens, such as viruses and worms, respectively. In some cases, dysregulation of these type 1 and type 2 responses has been associated with tissue-destructive inflammatory disease, including autoimmune diseases, and allergy, respectively. My laboratory uses characterized challenges in inbred strains of mice to define genetic determinants that underlie the proclivity to form type 1 or type 2 responses.