Affiliations: Department of Endocrinology, Instituto Nacional de Perinatología, México City, México | Department of Rheumatology, Instituto Nacional de Perinatología, México City, México | Laboratorios Clínicos de Puebla, Puebla, México | Centro de Hematología y Medicina Interna de Puebla, Clínica Ruiz, Puebla, México
Note:  Correspondence to: Adalberto Parra, MD, Instituto Nacional de Perinatología, Department of Endocrinology, Montes Urales 800, Lomas Virreyes, 11000 México, D.F., México. Tel.: +52 55 55209900 Ext. 299; E-mail: email@example.com
Abstract: Evidence supporting the role of PRL as a Th1-type cytokine and its potential therapeutic implications in human immunodeficiency virus (HIV) infection, graft-versus-host disease (GVHD), chronic hepatitis C (CHC) and preeclampsia is reviewed. In patients with HIV infection, dopaminergic adaptive mechanisms maintain PRL at a high but physiological concentration, which stimulates CD4+ T lymphocyte proliferation and increases viral apoptosis attempting to survive. In patients with hematologic malignancies after allogeneic hematopoietic stem cell transplantation complicated by chronic GVHD, the dopaminergic adaptive mechanisms tend to decrease the high normal serum PRL concentrations. On the contrary, in transplantations complicated by acute GVHD, donors with a Th1 cytokine profile may be prone to induce acute GVHD in their recipients, but a mild sustained rise in PRL concentrations after transplantation in these patients may reduce the severity of the disease. In patients with CHC, mild, drug-induced hyperprolactinemia is associated with increased peripheral lymphocytes and natural killer cell cytotoxicity that induces apoptosis in the infected hepatocytes. In early pregnancy, endogenous low-molecular-weight PRL (14–16 kDa) may act as a Th1-cytokine participating in the faulty trophoblastic invasion of the placenta in women with subsequent severe preeclampsia. In conclusion, PRL may participate as an important immunoregulatory factor in the pathophysiology of HIV infection, GVHD, CHC and preeclampsia through its Th1-type cytokine-like actions.
Keywords: Prolactin, Th1-type cytokine, HIV infection, graft versus host disease, chronic hepatitis C, preeclampsia