Gonadotropins are the hormones from the gonadotrope, a cell type in the pituitary, that regulate reproduction and sex steroids. The Nicholas lab has discovered a novel population of immune cells in the pituitary that impact gonadotrope function. The identities and functions of these immune cells remain unknown. Using transcriptomics, multiplexing, and systems biology approaches, our goal is to solve the puzzle of these immune cells. What immune cells are in the pituitary and why? Specifically, how do they regulate reproduction?