PRL and Autoimmunity: Under a specific genetic background, like estrogen, PRL has also been shown to promote the survival of self-reactive B cells by impairing B cell receptor-mediated clonal deletion and decreasing B cell apoptosis, thus breaking down B cell self-tolerance, leading to the development of autoimmunity (Elera-Fitzcarrald et al., 2017; Gonzalez, Saha & Peeva, 2013; Orbach & Shoenfeld, 2007; Saha et al., 2009, 2011).