Prolactin: A versatile regulator of inflammation and autoimmune pathology

•PRL has an immune-modulating potential.•PRL is endowed with tissue-regenerative properties.•PRL can promote, be dispensable or even protect against autoimmune pathology.

Prolactin (PRL) has long been proposed as an immune-stimulating and detrimental factor in autoimmune disorders. However, recent findings have challenged this common view, showing that PRL does not play a crucial role in the development of experimental autoimmune encephalomyelitis, animal model for multiple sclerosis (MS), and even protects against adjuvant-induced model of rheumatoid arthritis (RA). In this review we provide a critical overview of data supporting a role for PRL in the regulation of immune responses. In addition, we focus on studies exploring the involvement of PRL in autoimmune diseases, such as systemic lupus erythematosus, MS and RA, in light of the recently-outlined regenerative properties of this hormone.