Altered Immunity in Endometriosis: What Came First?

Background: This study was conducted to summarize current knowledge of the changes within the immune system, from action of macrophages, lymphocytes and NK cells to biological effects of their products. Endometriosis is a complex gynecological disorder defined as a presence of endometrial tissue outside the uterus affecting over 5 million reproductive-aged women in the U.S. alone.Result: In recent years, the potential role of the immune system in the development of endometriosis has increasingly gained attention. Data summarized in our study showed that the most relevant immunocytes are macrophages residing inside the peritoneal cavity and the ratios of Th1 to Th2 cells. Another crucial immunological parameter is the balance in production of cytokines and chemoatractants.Conclusions: This review confirms that despite decades of intensive research, the involvement of the immune system remains elusive, as we can recognize the changes, but still do not understand if these changes represent the results of endometriosis or if they are contributing factors. Based on these findings, we also discuss new treatment possibilities.