The female reproductive tract is a unique immune environment, designed to tolerate invasion by the growing embryo, while actively fighting infections. It has been known for some time that this ability to fight infections fluctuates during the menstrual cycle. This Results in a “window of vulnerability” that overlaps the time of implantation, during which there is a limited response to sexually transmitted infections (STIs).
Interferon epsilon (IFNe) is constitutively expressed in the female reproductive tract and is required for adequate protection against STIs. The expression levels of IFNe changes during the menstrual cycle and this prompted further study into the regulation of the immune genes in the human female reproductive tract during the menstrual cycle.
The Biomark fluidigm chip was used to study the expression of innate immunity genes in the female reproductive tract throughout the menstrual cycle, with a specific focus on IFNe. Samples were taken from three sites of the reproductive tract during the follicular and secretory stage and levels of estrogen and progesterone were recorded. Gene expression data was normalized using methods in the HTQPCR package and then converted to a data object to analyse using the linear model methods in Limma.
Using this process we were able to determine how genes involved in innate immunity change during the menstrual cycle and how they are affected by hormone levels. We determined that IFNe levels alter significantly during the menstrual cycle as well as determine candidate genes that may be regulated locally and distally by IFNe along the reproductive tract.