Growth hormone and prolactin are paracrine growth and differentiation factors in the haemopoietic system

Abstract

The pituitary secretory proteins growth hormone (GH) and prolactin (PRL) do not, as yet, have major roles in haematology or immunology. Recent evidence indicates that these hormones are haemopoietic growth factors and exert immunomodulatory functions at physiological concentrations. Here Robert Hooghe and colleagues discuss the significance of these hormones on different aspects of the immune system.