DETERMINATION OF ANTIGEN LEVELS: T-PLASTIN, TRANSGELIN AND CA-125 IN BABOONS WITH INDUCED ENDOMETRIOSIS

Endometriosis is defined as the presence of endometrial-like tissue outside the uterine cavity and is associated with chronic intra-pelvic inflammation. Its symptoms, which are often severe, have a negative impact on a woman’s quality of life. They include chronic pelvic pain and infertility. It is estimated that about 10% women in their reproductive ages are affected by the disease globally. Currently, diagnostic methods are laparoscopy with histological confirmation and non-invasive such as ultrasound and the quantification of CA-125 biomarker in serum. CA-125 is known to be elevated in endometriosis, however it does not have sufficient diagnostic power as a single biomarker of endometriosis. Due to this, there is a need to determine other antigens that would act as potential biomarkers for endometriosis. It has been observed that Transgelin and T-Plastin are upregulated in endometriosis lesions and in secretory phase of endometrium respectively. There is insufficient data available showing the concentration of T-plastin in serum or plasma in the development of endometriosis. The main objective of this study was to identify whether T-plastin, Transgelin and CA-125 are potential biomarkers in early diagnosis of endometriosis using animal model for endometriosis. The baboon model represents clinically relevant research models for endometriosis. This study compared the levels of T-plastin, Transgelin and CA-125 in the peripheral blood and peritoneal fluid of baboons before and after induction of endometriosis. In this prospective, case-control study, ten female baboons ( Papio anubis , 9-15 kg each) of proven fertility that have had at least one menstruation during captivity, were induced by intra-pelvic injection of menstrual endometrium on day 1 or 2 of menstruation followed by staging laparoscopy. Serum and peritoneal fluid samples were collected prior to induction to serve as controls.T-Plastin, Transgelin and CA-125 were measured using commercially available ELISA Kits. Data was analyzed using non-parametric test and level of significance at p<0.005. T-Plastin and Transgelin had insignificant p values in both peripheral blood and peritoneal fluid while CA-125 showed p=0.0003 in peripheral blood and p=0.0279 in peritoneal fluid. Diagnostic performance of individual biomarkers was determined by Receiver Operating Characteristic (ROC) with the Area under the curve (AUC) equal to 0.5 showing T-Plastin and Transgelin in both serum and peritoneal fluid unreliable for use as biomarkers in endometriosis. CA-125 levels in peritoneal fluid had an AUC of 0.7900 indicating it can be used as potential biomarkers for endometriosis. Key words: Endometriosis, biomarkers, T-Plastin, Transgelin, CA-125, ELISA, Olive Baboons. DOI : 10.7176/ALST/75-06 Publication date :August 31 st 2019