The Hyaluronic Acid System is Intact in Menstrual Endometrial Cells in Women With and Without Endometriosis

Objective: To characterize the production and degradation of hyaluronic acid (HA) in menstrual endometrial epithelial cells (EECs) and endometrial stromal cells (ESCs) in women with and without endometriosis. To identify the presence of CD44, the primary receptor of HA, in menstrual EECs and ESCs in women with and without endometriosis. Design: In vitro study. Setting: Academic center. Patient(s): Deidentified patient samples from women with and without endometriosis. Interventions: EECs and ESCs were isolated from menstrual endometrial biopsies performed on women with (N = 9) and without (N = 11) endometriosis confirmed by laparoscopy. Main Outcome Measure: Real-time polymerase chain reaction, Western blot, and immunohistochemistry were used to assess hyaluronic acid synthase (HAS) isoforms 1, 2, and 3; hyaluronidase (HYAL) isoforms 1 and 2; and standard CD44. Student t test was used to analyze the results. Results: There was no significant difference in messenger RNA (mRNA) or protein expression of HAS2, HAS3, HYAL1, or HYAL2 in EECs or ESCs from women with or without endometriosis. HAS1 mRNA was variably detected, whereas HAS1 protein was similarly expressed in EECs and ESCs from women with and without endometriosis. Standard CD44 was expressed in both cell types, and expression did not differ in cells from women with or without endometriosis. Conclusions: The HA system is expressed in eutopic menstrual ESCs and EECs from women with and without endometriosis. There are no differences in expression in HA production or degradation enzymes in EECs or ESCs from women with and without endometriosis. Standard CD44 expression does not differ in eutopic menstrual endometrial cells from women with and without endometriosis.