Francisella tularensis-infected macrophages release prostaglandin E2 that blocks T cell proliferation and promotes a Th2-like response.

Woolard MD, Wilson JE, Hensley LL, et al. "Francisella tularensis-infected macrophages release prostaglandin E2 that blocks T cell proliferation and promotes a Th2-like response." J. Immunol.. 2007;178(4):2065-74.