@article {1590982,
	title = {Gamma Interferon Is Required for Chlamydia Clearance but Is Dispensable for T Cell Homing to the Genital Tract},
	journal = {American Society for Microbiology},
	year = {2020},
	abstract = {
	While there is no effective vaccine against\&nbsp;Chlamydia trachomatis\&nbsp;infection, previous work has demonstrated the importance of\&nbsp;C. trachomatis-specific CD4+\&nbsp;T cells (NR1 T cells) in pathogen clearance. Specifically, NR1 T cells have been shown to be protective in mice, and this protection depends on the host{\textquoteright}s ability to sense the cytokine gamma interferon (IFN-γ). However, it is unclear what role NR1 production or sensing of IFN-γ plays in T cell homing to the genital tract or T cell-mediated protection against\&nbsp;C. trachomatis\&nbsp;Using two-photon microscopy and flow cytometry, we found that naive wild-type (WT), IFN-γ-/-, and IFN-γR-/-\&nbsp;NR1 T cells specifically home to sections in the genital tract that contain\&nbsp;C. trachomatis\&nbsp;We also determined that protection against infection requires production of IFN-γ from either NR1 T cells or endogenous cells, further highlighting the importance of IFN-γ in clearing\&nbsp;C. trachomatis\&nbsp;infection.IMPORTANCE\&nbsp;Chlamydia trachomatis\&nbsp;is an important mucosal pathogen that is the leading cause of sexually transmitted bacterial infections in the United States. Despite this, there is no vaccine currently available. In order to develop such a vaccine, it is necessary to understand the components of the immune response that can lead to protection against this pathogen. It is well known that antigen-specific CD4+\&nbsp;T cells are critical for\&nbsp;Chlamydia\&nbsp;clearance, but the contexts in which they are protective or not protective are unknown. Here, we aimed to characterize the importance of gamma interferon production and sensing by T cells and the effects on the immune response to\&nbsp;C. trachomatis\&nbsp;Our work here helps to define the contexts in which antigen-specific T cells can be protective, which is critical to our ability to design an effective and protective vaccine against\&nbsp;C. trachomatis.



	Keywords:\&nbsp;Chlamydia; IFN-γ; T cells; genital tract immunity; interferons; mucosal immunity; mucosal pathogens.

},
	url = {10.1128/mBio.00191-20},
	author = {Jennifer D Helble and Rodrigo J Gonzalez and von Andrian, Ulrich H and Starnbach, Michael N}
}
