Abstract
Chlamydia invades multiple mucosal tissues in humans and animals. The body's first line of defense against chlamydial infection is provided by innate immunity, whereas adaptive immunity plays a crucial role in managing the infection's progression and preparing the immune system to combat reinfection. Host resistance to chlamydial infection necessitates a coordinated effort between innate and adaptive immune cells. Numerous cell types are capable of producing interferon gamma (IFN-γ) as a defense mechanism against chlamydial infection, thereby effectively mediating the clearance of infection. However, the distinct roles of various immune cell populations in responding to chlamydial infection, as well as their functions during infection progression, remain poorly understood. Therefore, we will discuss the various roles of IFN-γ released by different immune cells in chlamydial infection, focusing primarily on experimental animal models and a review of available data from in vivo cellular immunological studies in humans.