Estrogen Protects against Vaginal Transmission of Simian Immunodeficiency Virus

• Published in: The Journal of infectious diseases Vol. 182; no. 3; pp. 708 - 715
• Main Authors: Smith, Stephen M., Baskin, Gary B., Marx, Preston A.
• Format: Journal Article
• Language: English
• Published: Chicago, IL The University of Chicago Press 01-09-2000; University of Chicago Press; Oxford University Press
• Subjects: Action of physical and chemical agents; AIDS; Animals; Biological and medical sciences; Disease Models, Animal; Disease transmission; Epithelium; Estrogens; Estrogens - pharmacology; Female; Fundamental and applied biological sciences. Psychology; HIV; HIV 1; Human immunodeficiency virus; Human immunodeficiency virus 1; Infections; Inoculation; Macaca mulatta; Major Articles; Microbiology; Mucous Membrane - drug effects; Mucous Membrane - virology; Ovariectomy; Primates; Progesterone; Progesterone - pharmacology; Simian Acquired Immunodeficiency Syndrome - transmission; Simian immunodeficiency virus; Vagina - drug effects; Vagina - virology; Virology; Viruses; Animal model; Chemoprophylaxis; Estrogen; Macaca mulatta; Prevention; Primates; Simioidea; Female; Immunopathology; Exogenous; Retroviridae; AIDS; Immune deficiency; Lentivirus; Ovarian hormone; Biological activity; Infection; Virus; Vertebrata; Mammalia; Viral disease; Vertical transmission; Progesterone; Sex steroid hormone; Simian immunodeficiency virus
• ISSN: 0022-1899; 1537-6613
• DOI: 10.1086/315776

Postmenopausal women and women who use injectable, progestin-based contraceptives are at increased risk of human immunodeficiency virus (HIV) infection, suggesting that progesterone and estrogen affect HIV-1 vaginal transmission. To evaluate the individual roles of these sex hormones in vaginal transmission, ovariectomized female macaques were treated with either progesterone or estrogen followed by intravaginal inoculation with SIVmac. All 6 untreated control macaques and 5 (83%) of 6 progesterone-treated animals became infected following intravaginal SIV inoculation. Conversely, none of 6 estrogen-treated macaques was infected. Vaginal subepithelial inoculation of estrogen-treated animals resulted in infection, which shows that the block occurred at the vaginal epithelium and/or lumen. These data suggest that estrogen-deficient women are at increased risk of HIV infection, because their vaginal microenvironments are rendered more susceptible. Moreover, topical vaginal estrogen therapy may be an effective means of reducing HIV vaginal transmission in these high-risk groups.