IL5 and breast cancer: To extend our mechanistic discoveries from breast cancer to other cancer models, we investigated the impact of TSLP-activated CD4+ T cells and their downstream effector cytokines (IL-3, IL-5, and GM-CSF) on a well-established pancreatic cancer model (P48-Cre LSL-KrasG12D p53f/f; Hingorani et al., 2003).