The vulnerability to certain infections like malaria, Listeria, HIV, and herpes simplex virus is high in women who are pregnant or using synthetic progesterone birth control injections.
A new research report appearing in the March 2013 issue of the Journal of Leukocyte Biology offers strong evidence for a possible explanation: the progesterone receptor, a pregnancy hormone sensor, targets a part of the immune system responsible for protection against these and other invaders. In addition to helping explain why some women are more vulnerable to certain infections, it also sheds light on why some autoimmune diseases, notably rheumatoid arthritis and multiple sclerosis, often go into remission during pregnancy.
"We hope that continued work in this area will ultimately yield better approaches to the prevention of immunological complications of pregnancy, safer and more effective forms of hormonal birth control and novel biological targets for the treatment of autoimmune diseases," said Grant C. Hughes, M.D., a researcher involved in the work from the Division of Rheumatology and Department of Immunology at the University of Washington in Seattle, WA.
"Pregnancy and hormones have long been known to influence immune responses, but these processes have been poorly understood, said John Wherry, Ph.D., Deputy Editor of the Journal of Leukocyte Biology. "This new work is significant for two reasons. First, the identification of progesterone receptors as a mechanism of immune modulation during pregnancy sheds light on the pregnancy-immune phenomenon, and second, these studies define a potentially new target to modulate autoimmunity and immune-mediated problems during pregnancy."